Chapter #1st INTRODUCTION TO BIOLOGY
- Science: Word science is derived from scientia means knowledge. Science is the study in which observations are made, experiments are done and logical conclusions are drawn in order to understand the principles of nature.
- “OR” The knowledge obtained through observations and experiments is called science.
- Biology: The word “biology” derived from two Greek words “Bios” meaning life and “Logos” meaning study, so the scientific study of life is called biology. “OR” “The study of living things is called biology”.
- Botany –Greek: botane means plant.
“Branch of biology which deals with the scientific study of plants is called Botany”.
Zoology – Greek: Zoon means animals.
“ The branch of biology that deals with animals is called zoology.
- Microbiology – Greek: mikros means small.
“The branch of biology that deals with microorganisms and their effects on other living organisms”
- Morphology – Greek: Morph means structure
“A branch of biology which deals with the study of form and structure of organisms is called morphology”.
- Anatomy – Greek: Anatome means dissection / cutting
“A branch of biology which deals with the study of internal structure of organisms is called anatomy”
- Physiology – Latin: Physiologia means function
“A branch of biology which deals with the study of the functions of living organisms and their parts is called physiology”
- Embryology / Developmental Biology – Greek: Embryon means growth.
: It is the study of the development of an embryo to new individual.
- Cell Biology/ Cytology – Greek: Cyto means cell
“The study of structure and function of the cell and cell organelles is called cell biology.”it also deal with cell division.
- Histology – Greek: Histos means tissue
“A branch of biology which deals with the microscopic study of tissue is called histology”
- Paleontology – Greek: Palaios means primitive/fossil/being ancient.
It is the study of fossils, which are the remains of extinct organisms. Paleontology has further two branches,
- a)paleobotany: Study of plants fossils is called paleobotany.
- b) Paleozoology: study of animals fossils is called paleozoology.
Immunobiology /Immunology – Latin: Immunis means body defence system / not affected by disease.
“A branch of biology which deals with the study of immunity is called as immunology.
- Entomology – Greek: Entomos means Insect.
The study of insects is called entomology.
Genetics – Greek: Genos means race/kind/ancestry/heredity/origin.
The study of genes and their role in inheritance is called genetics. OR “Branch of biology which deals with the study of inheritance is called genetics.
- Microbiology – Greek: mikros means small
“A branch of biology which deals with the study of small and microscopic organisms (microorganisms/microbes) and their interactions with other living things is called microbiology.
- Biotechnology –It deals with the practical application of living organisms to make substances for the welfare of mankind.
- Environmental Biology / Ecology – Greek: Oikos means house/habitation: It deals with the study of the interactions between the organisms and their environment.
- Parisitology – Greek: Parasitos means some body that eats another’s food/grains
“A branch of biology which deals with the study of parasites is called parasitology. Parasites are the organisms that take food and shelter from living hosts and, in return, harm them. E.g: Cuscute, bed bug, etc.
- Social biology – Latin: Socialis means companion : This branch deals with the study of social behaviour of the animals that make societies. OR
“A branch of biology which deals with the study of those organisms which are living together in a community and interact each other is called social biology, e.g. social insects (ants, bees, and termites), birds flock, humans and fish living in groups.
- Pharmacology – Greek: Pharmakon means drugs ; It is the study of drugs and their effects on the systems of human body. OR
“A branch of biology which deals with the study and practical application of preparation, use, and effects of drugs and synthetic medicines is called pharmacology.
- Molecular biology (biochemistry): deals with the study of the molecules of life; e.g. water, proteins, carbohydrates, lipids, and nucleic acids.
- Biophysics:It deals with the study of the principles of physics, which are applicable to biological phenomena. For example there is a similarity between the working principles of lever in physics and limbs of animals in biology.
- Biochemistry: It deals with the study of the chemistry of different compounds and processes occurring in living organisms. For example the study of basic metabolism of photosynthesis and respiration involves the knowledge of chemistry.
- Biomathematics / Biometry:It deals with the study of biological processes using mathematical techniques and tools. For example to analyze the data gathered after experimental work, biologists have to apply the rules of mathematics.
- Biogeography:It deals with the study of the occurrence and distribution of different species of living organisms in different geographical regions of the world.
- Fossil: Dead remains of plants and animals burried in rocks are called fossils. Dead remains of plants are called plant fossils while dead remains of animals are called animal fossils.
- Inheritance: Characters that are transmitting from parents to off-springs are called inheritance.
- Colony: In Biology a colony refers to individual organisms of the same species living closely together , usually for mutual benefit , such as stronger defence or the ability to attack bigger prey. E.g volvox is a green alga form spherical colonies of up to 50,000 cells.
- Protist: Any of eukaryotic organism belong to kingdom protista that show characters both like plants and animals and are mostly unicellular or colonial. e.g, Amoeba.
- Surgery: The branch of medicines that employs operations in the treatment of diseases or injury.
- Volvox : Volvox is a green alga from genus cholorophyta that form spherical colonies of upto 50,000 cells.
- Medicine: “A substance used in the diagnosis, treatment, or prevention of a disease is called medicine.
- Agriculture: The science of cultivating crops like wheat, maize, rice and farming of animals that gives milk and meat.
- Animal Science / Animal husbandry: Animal science is related to breeding and veterinary (medical or surgical treatment) of animals.
- Horticulture: Latin hortus, garden. “The science of cultivating fruits, vegetables, flowers, or ornamental plants”
- Forestry: Forestry is the scientific management of forest lands for wood , wildlife, and recreation.
- Farming: It deals with the development and maintenance of different types of farms.
- Micromolecules: molecules with low molecular weight are called micromolecules. e.g. glucose, water etc.
- Macro molecules: Molecules with high molecular weights are called macromolecules. e.g. starch, proteins, lipids etc.
- Organelle : The building blocks of a cell are called organelle.
- Cell : Cell is the basic structural and functional unit of life.
- Tissue : Tissue is a collections of similar cells working together to perform a specific job. E.g, epithelial tissues, connective tissues, etc.
- Organ: Two or more types of tissues work together to complete a specific task is called organ. E.g, heart, stomach, brain, etc.
- Organ system (system) : several organs working in union to achieve a common goal is called organ system. E.g, digestive system, cardiovascular system, respiratory system, etc.
- Organism level or Individual level : several organ systems functioning together forms an organism. E.g, human, dog, tree, frog, mustard,etc.
- Specie: A species is defined as a group of organisms capable of interbreeding and producing fertile offspring.
- Population : A group of organisms of the same species located at the same place, in the same time and sharing the same resources is called population. Individual organisms of the same species working together to achieve a common goal. Examples: population of human, population of mustard, population of frogs, etc.
- Community : A community is an assemblage of different populations, interacting with one another within the same environment. A forest may be considered as a community. It includes different plant, microorganisms, fungi and animal species.
- Biosphere: The part of the Earth inhabited by organisms’ communities is known as biosphere.
- Cellular organization : The arrangement of cells in a specific passion to make an entire living organism is called Cellular organization.
- Unicellular Organization: In this type of organization an organism is composed of only one cell. Those type of organisms are called unicellular organisms. Examples: Amoeba, Paramecium, and Euglena, Bacteria, etc.
- Colonial Organization: In colonial type of cellular organization, many unicellular organisms live together but do not have any division of labour among them. And doesnot depend on each other.Volvox is a green alga found in water that shows colonial organization. Hundreds of Volvox cells make a colony.
- Multicellular organization: In multicellular organization, cells are organized in the form of tissues, organs and organ systems. Frog and mustard are the familiar examples of multicellular organization.
Chapter # 2 SOLVING A BIOLOGICAL PROBLEM
- Scientific method: A way to gather information and answer questions in science is called scientific method. “OR” A method used by scientists to solve scientific problems is called scientific method. “OR” The scientific method is a process for experimentation that is use to explore observations and answer questions.
- Biological method: The scientific method in which biological problems are solved is called biological method. OR “A method used by biologists to solve biological problems is called biological method.
- Biological problem: A biological problem is a question related to living organisms that is either asked by some one or comes in biologist’s mind by himself “OR” The problem faced by a biologist during biological experiments , study or research is called biological problem.
- Observations: The act of noticing something is called observation.
- Quantitative observations: Observations that are measurable are called Quantitative observations. E.g: size of the plants, number of petals, etc.
- Qualitative observations: Observations that are descriptive and non measurable are called qualitative observations. E.g, color of flower, taste , etc.
- Hypothesis: Tentative explanation of observations is called a hypothesis. “OR”
- A hypothesis is an educated guess or statement made by biologist about a certain process on the basis of available information.
- Deduction: Logical conclusion drawn from hypothesis are called deductions.
- Experimentation: The act of Performing experiments is called experimentation.
- Theory: When a hypothesis is given a repeated exposure to experimentation and is not falsified, then it is called theory.
- Scientific Principal or Law: When a theory can explain many natural phenomena and consistently supported by experiments, and also universally accepted by scientists it becomes a scientific principal or Law.
- DATA : Data can be defined as the information such as names, dates or values made from observations and experimentation. “OR” Recorded observations is called data. “OR” Collection of facts and figures is called data.
- Experimental group: It is a group in a scientific experiment where experimental procedure is performed.
- Control group: The group in an experiment that is used as a standard for comparison is called control group.
- Experiment: An operation or procedure carried out under controlled conditions in order to discover an unknown effect or law, to test or establish a hypothesis, or to illustrate a known law.
Chapter # 3 BIODIVERSITY
- Biodiversity: The term “biodiversity” has been derived from ‘bios’ and ‘diversity’. Biodiversity is a measure of the variety of organisms present in different ecosystems or earth surface.
- Flora: Diversity of plants in an ecosystem is called flora.
- Fauna: Diversity of animals in an ecosystem is called flora.
- Taxonomy: The branch of biology deals with the identification, nomenclature and classification of living organisms is called taxonomy.
- Systematics: The branch of biology that deals with classification and also traces the evolutionary history of organisms is known as systematics.
- Classification: The arrangement of organisms into groups and sub-groups on the basis of similarities and differences is called classification.
- Taxonomic Hierarchy: The groups into which organisms are classified are known as taxonomic categories or taxa (singular “taxon”). “OR” Any group in the taxonomic categories or taxanomic classification is termed as taxon. A ladder like structure formed by taxanomic categories is known as Taxanomic hierarchy.
- Phylum (Division: for plants and fungi): A phylum is a group of related classes.
- Class: A class is a group of related orders.
- Order: An order is a group of related families.
- Family: A family is a group of related genera.
- Genus: A genus is a group of related species.
- Species: Organisms that can freely interbreed and produce fertile offsprings are called species. It is the basic unit of classification.
- Prokaryotic cell: Cell that donot have membrane bounded nucleus and membrane bounded organelles is called prokaryotic cell.
- Prokaryotes “OR” Monerans: Organisms having prokaryotic cells are called prokaryotic organisms or monerans.
- Eukaryotic cell: Cell that have membrane bounded nucleus and organelles is called eukaryotic cell.
- Eukaryotes: Organisms that have eukaryotic cells are called eukaryotic organisms.
- Protists: It includes eukaryotic unicellular and simple multicellular organisms that have both plant and animal like characteristics.
- Fungi:Fungi are eukaryotic multicellular heterotrophs which are absorptive in their nutritional mode.
- Plants: plants are eukaryotic organisms that prepare their own food by photosynthesis.
- Animals: Ingesting eukaryotic, heterotrophic organisms are called animals.
- Virus: Viruses are at the borderline of living and nonliving. They show characteristics both like living and non living.
- Nomenclature: A system of naming organisms is called nomenclature.
- Binomial Nomenclature: A system of giving two word name to an organism is called Binomial nomenclature.
- Conservation:The protection of animals, plants, and natural resources is called conservation.
- In-situ conservation: The conservation of elements of biodiversity in their natural habitat is referred to as in-situ conservation. Example: National park.
- Ex-situ conservation: The conservation of elements of biodiversity out of their natural habitat is referred to as ex-situ conservation. Zoo and Botanical gardens are example of this type of conservation.
- Extinct Species: A species is called extinct when there is no doubt that the last individual of that species has died in that ecosystem. E.g, Dinosaur.
- Endangered Species: A species is called endangered when it is at risk of extinction in near future. Examples of endangered animal species are lion, tiger, Asiatic cheetah, Indian one-horned rhinoceros, swamp deer, Indian wild ass, hangul, black buck etc.
- Hot spots: A region of high conservation patriority is known as hot spot.
- Deforestation: Cutting down or removal of the forests is known as deforestation.
- Acellular OR A cellular bodies: Living creatures not consisting of cells are called a-cellular bodies. These particles show some characteristics of the cell or living
- Sub cellular bodies: Sub cellular bodies are living and non living components of cells enclosed by the cell membrane.
- Soil eros ion: The washing away of the top layer of soil is called soil erosion.
- Viroid : An infectious agent similar to a virus but consisting of only a short, single strand of RNA without a protein coat is called viroid. Viroids cause infections in plants.
- Prions: Infectious proteins are called prions.
- WWF: World wildlife fund(WWF) is the world largest conservation organization that protect natural resources, specially organisms and their habitat from various impacts.
Chapter # 4 CELLS AND TISSUES
- Microscope; An optical instrument used for viewing very small objects, such as mineral samples or animal or plant cells, typically magnified several hundred times.
- Microscopy:- Microscopy is the use of microscope to observe minute living organisms.
- Light Microscope:- A Microscope that works on the principle of light is called light microscope.
- Magnifying glass or simple microscope: a lens that produces an enlarged image, typically set in a frame with a handle and used to examine small or finely detailed things.
- compound microscope:- an optical instrument for forming magnified images of small objects, consisting of an objective lens with a very short focal length and an eyepiece with a longer focal length.
- Electron Microscope:-Type of microscopes that use electrons OR electric current to produce magnified images is called electron microscope.
- Scanning electron microscope:- an electron microscope in which the surface of a specimen is scanned by a beam of electrons that are reflected to form an image.
- Transmission electron microscope;- a form of electron microscope in which an image is derived from electrons which have passed through the specimen, in particular one in which the whole image is formed at once rather than by scanning.
- Magnification:- Magnification is the increase in apparent size of an object.
- Resolution;- Resolution or resolving power is the measure of the clarity of an image.
- CELL WALL;- The outer rigid protective layer of plants , bacteria and fungal cells is called cell wall.
- Cell membrane or plasma membrane:- A thin membrane covering cytoplasm of a cell is called plasma membrane.
- Cytoplasm:- The semi transparent and semi viscous substance present between cell membrane and nucleus is called cytoplasm.
- Cytoskeleton:- The cytoskeleton is a series of intercellular proteins that help a cell with shape, support, and movement.
- Organelle:- Organelles are small structures within cells that perform dedicated functions
- NUCLEUS:- (Nucleus or kernal means central thing) It is the main organ in a eukaryotic cell that controls functions of all other organelles.
- Ribosomes (The protein synthesizing factory) :- (ribo from ribose or ribonucleic acid and soma means body) : Ribonucleic acids are small granular bodies involved in protein synthesis.
- Mitochondria or chondriosome (singular mitochondrion ,. Mitos means thread and chondrion means granules). An organelle found in large numbers in most cells, in which the biochemical processes of respiration and energy production occur.
- Plastids:- (Plastos means molded) Plastids are membrane bounded organelles found in plants and photosynthetic protists ( algae).
- Chloroplast: The food producing plastid of the cell is called chloroplast.
- Leucoplasts: The type of plastid that has no colour and is involved in the storage of starch, lipid and protein.
- Chromoplasts :- (chroma means colour and plastos means molded) Chromoplasts are plastids that produce and store pigments.
- Endoplsmic Reticulum (E.R)(endo means inner, plasma means fluid and reticulum means network of channels) :- Endoplsmic Reticulum is a network of interconnected channels that extends from cell membrane to nuclear envelope.
- Rough Endoplasmic Reticulum (R.E.R):- Endoplasmic reticulum with attached ribosome to it is called R.E.R.
- Smooth Endoplsmic reticulum (S.E.R):- Endoplasmic reticulum without attached ribosome is called S.E.R.
- GOLGI APPARATUS OR GOLGI BODIES OR GOLGI COMPLEX OR DICTYOSOMES:- A Set of flattened sacs stacked over each other in eukaryotic cell is called golgi body.
- LYSOSOMES:- (LYSO means Splitting, Break down or dissolution and Soma means Body) These are single membrane bounded organelles involved in the break down of materials.
- Centrioles:- A centriole is a small set of microtubules arranged in a specific way. “Or” Centrioles are hollow cylindrical organelles found in the cells of animals and many unicellular organisms.
- Vacuoles:- Vacuoles are fluid filled single membrane bounded organelles.
- Central Vacuole:– This type of vacuole is present in plant cell and is responsible mostly for storage of water.
Contractile Vacuole;- This type of vacuoles are movable and are present in unicellular organisms. Contractile vacuole eliminate waste from the cell.
Food vacuoles:- Food vacuole take in materials in the form of food from outside and also store them.
- Diffusion: Diffusion is the movement of molecules from an area of higher concentration to the area of lower concentration i.e. along concentration gradient.
- Facilitated diffusion:- The movement of molecules from a region of higher concentration to a region of lower concentration with the help of transport proteins is called Facilitated diffusion.
- Osmosis: Osmosis is the movement of water across a semi-permeable membrane from a solution of lesser solute concentration to a solution of higher solute concentration.
- Hypotonic solution: A Hypotonic solution has relatively less solute.
- Isotonic solution: isotonic solutions have equal concentrations of solutes.
- Hypertonic solution: Hypertonic solution has relatively more solute.
- Turgor Pressure:- Pressure exerted by fluid in a cell that presses the cell membrane against the cell wall.
- Plasmolysis (Flaccidity) : The loss of water by osmosis from a plant cell to the extent that the cytoplasm shrinks away from the cell wall.
- Deplasmolysis: The return of the protoplast of the plasmolysed cell to its initial state by the entrance of water is called deplasmolysis.
- Filtration: Filtration is a process by which small molecules are forced to move across semipermeable membrane with the aid of hydrostatic (water) pressure or blood pressure.
- Active transport:-Active transport is the movement of molecules from an area of lower concentration to the area of higher concentration.
- ENDOCYTOSIS : It is the process by which bulky materials are imported into the cell.
- EXOCYTOSIS : It is the process through which bulky material is exported out of the cell.
- Tissue:- A group of cells that perform a specific function is called tissue.
- Animal tissues:- Tissues found in animals are called animal tissues.
- Plant tissues : Tissues found in Plants are called plant tissues.
- Passive transport: The transport of materials from a region its higher to a region of lower concentration without the expenditure of energy is called passive transport.
- Phagocytosis: The process through which cell takes in large solid materials is known as phagocytosis.
- Pinocytosis: The process through which cell takes in liquid materials is known as pinocytosis.
- Selectively permeable membrane: Membrane that pass some of the materials while stop others is called selectively permeable membrane. Example: plasma membrane, nuclear membrane, etc.
- Permeable membrane: Membrane that pass most of the materials through it is called permeable membrane. E.g, cloth.
- Non-Permeable membrane: The membrane that do not allow materials to pass through it is called non permeable membrane. Example: polythene bag.
- Cell Theory: A theory in biology that includes one or both of the statements that the cell is the fundamental structural and functional unit of living matter and that the organism is composed of cells with its properties being the sum of those of its cells.
Chapter#5 CELL CYCLE
- CELL CYCLE;- Cell cycle is the series of events from the time a cell is produced until it completes mitosis and produces new cells.
- Non-sister chromatids : Either of the two chromatids of any of the paired homologous chromosomes.
- Sister chromatids: Chromatids of the same chromosomes are called sister chromatids.
- Kinetochore: The place on either side of the centromere to which the spindle fibers are attached during cell division is called kinetochore.
- chromatids: One of the two strand of a chromosome is called chromatid.
- Benign: Type of tumor that does not invade surrounding tissues or spread to other parts of the body.
- M-phase: The phase in cell cycle during which division of the cell take place is called mitotic phase or M-phase or cell division phase.
- Phragmoplast: The cytoplasmic structures that forms at the equator of the cell after the chromosomes have divided during the anaphase of cell division and that indicates cell division.
- Malignant tumor : Type of tumor that invade surrounding tissues or spread to other parts of the body is called malignant tumor.
- Chiasmata: Chiasmata is the point of attachment of non sister chromatids of homologous chromosomes.
- Metaphase plate: A plane in the center of the cell in dividing cell on which the chromosomes are arranged during metaphase stage of the cell division.
- Spindle fibers: These are protein filaments produced by centrioles on which the chromosomes moves during cell division.
- G 0 phase: G-0 Phase or resting phase is a period in the cell cycle in which cell exists in a quiscent. During this phase the cell never divides nor preparing to divide.
- Interphase: the preparatory phase of cell cycle during which a cell increases in size and produces all the materials requires for cell division is called interphase.
- Centromere: The center of chromosome through which two chromatids are attached is called centromere.
- Budding: Budding is a type of asexual reproduction in which an outgrowth appears from the parents body, then detaches and forms a new individual. “or” budding is the appearance of an outgrowth due to increase cell division.
- Mitosis;- A type of somatic cell division that results in two daughter cells each having same number and kind of chromosome as in the parent cell.
- Karyokinesis: (karyo from karyon means nucleus and kinesis means division). The division of the nucleus of cell is called karyokinesis.
- cytokinesis ;- (cyto means cytoplasm of cell and kinesis means division); The division of cytoplasm of the cell is called cytokinesis.
- Cancer: A disease caused by an uncontrolled division of abnormal cells is called cancer or tumor. And the affected cells are called cancerous cells.
- Meiosis: (The word meiosis comes from Greek word ‘meioun’, meaning “to make smaller,” since it results in a reduction in chromosome number). Meiosis is the process by which one diploid (2n) eukaryotic cell divides to generate four haploid (1n) daughter cells.
- Haploid Cell: The cell that contains half the number of chromosomes or unpaired chromosomes is called haploid cell.
- Diploid cell: The cell that contains paired chromosomes are called diploid cells.
- Synapsis: The pairing of homologous chromosomes is called synapsis.
- Homologous Chromosomes: Chromosomes that are same in size and shape are called homologous chromosomes.
- Crossing over: The exchange of segments by non sister chromatids of homologous chromosomes is called crossing over.
- Chiasmata : Chiasmata is the point of attachment of non sister chromatids of homologous chromosomes.
- Apoptosis: Apoptosis is a type of programmed cell death that remove unwanted cells from the body.
- Necrosis: Necrosis is the accidental death of cells and living tissues.
- Disjunction: The normal separation or moving apart of chromosomes toward opposite poles of the cell during cell division is called disjunction.
- Nondisjunction: Nondisjunctionis the failure of homologous chromosomes or sister chromatids to separate properly during cell division.
- Lipase: Enzymes that break down lipids are called lipase.
- Amylase: Enzymes that act on starch are called amylase.
- Protease: Enzymes that act on proteins are called protease.
- Denaturation: The process of modifying the molecular structure of a protein is called denaturation.
- Optimum pH : The narrow range of PH at which enzymes works at their maximum rate is called as the optimum pH.
- Optimum temperature: The temperature at which enzymes works at their maximum rate is called as the optimum temperature.
- Enzyme-substrate complex: When an enzyme combined to its substrate an enzyme substrate complex is formed.
- Catalyst: A substance able to increase the rate of a chemical reaction without itself being consumed or changed by the reacting chemicals is called a catalyst.
- Enzymes OR Biocatalyst : Enzymes are proteins that catalyze (speed up) biochemical reactions by lowering its activation energy and are not changed during the reaction.
- ZMOLOGY OR Enzymology: The study of enzymes is called Enzymology or Zymology.
- Metabolism (metabolism means change): Metabolism is the set of biochemical reactions that occur in living organisms in order to maintain life.
- Anabolism: Anabolism includes the biochemical reactions in which larger molecules are synthesized. Example: Amino acids combined to form proteins.
- Catabolism: Catabolism includes the biochemical reactions in which larger molecules are broken down.
- Example: decomposition of proteins into amino acids.
- Substrate: Substances on which enzymes act are called substrates.
- Products: The substances formed after completion of an enzymatic reaction are called products.
- Activation energy: The minimum energy required to start a reaction is called activation energy.
- Apoenzyme: The protein part of an enzyme without cofactor is called apoenzyme.
- Holoenzyme: The apoenzyme along with cofactor attach to it is called holoenzyme or complete enzyme.
- Intracellular enzymes: Enzymes that perform functions inside the cells are called intracellular enzymes. (E.g. enzymes of glycolysis work in the cytoplasm).
- Extracellular enzymes: Enzymes that perform functions outside the cells are called Extracellular enzymes. (E.g. pepsin enzyme working in the stomach cavity).
- Cofactor: The non-protein substances that bind with enzymes and enhance their actions are called cofactors.
- “OR” any of various organic or inorganic substances necessary to the function of an enzyme.
- Prosthetic groups : Prosthetic groups are cofactors that bind tightly to proteins or enzymes. They can be organic or metal ions and are often attached to proteins by a covalent bond. E.g, zinc, copper,iron,
- Coenzymes: Organic cofactors that are loosely attached with enzymes are called coenzymes. E.g, vitamins (riboflavin, thiamine and folic acid)
- Bioenergetics : Bioenergetics is the study of energy relationships and energy transformations (conversions) in living organisms.
- Acetyl CO-A: A compound C25H38N7O17P3S formed as an intermediate in metabolism and active as a coenzyme in biological acetylations.
- Acetyl: The radical CH3CO- of acetic acid is called acetyl. It is formed by the removal of a hydroxide (OH) ion from the acetic acid (CH3COOH).
- Acetylation: The addition of acetyl to any substance is called acetylation.
- Chlorophyll: Magnessium containing pigments involved in photosynthesis.
- NAD: (Nicotinamide adenine dinucleotide): A coenzyme C21H27N7O14P2 of numerous dehydrogenases that occurs in most cells and plays an important role in metabolism as an oxidizing agent or when in the reduced form as a reducing agent for various metabolites.Also called diphosphopyridine nucleotide (DPN).
- Adenine: organic compound belonging to the purine family, that is the basic component of nucliec acids, ATP, etc.
- Coenzyme-A: A coenzyme C21H36N7O16P3S that occurs in all living cells and is essential to the metabolism of carbohydrates, fats, and some amino acids.
- ADP: Energy-carrying two phosphorous, adenine and ribose containing molecule found in the cells of all living things.
- Photolysis: (phot means light and lysis means break down) The breakdown of compounds with the help of light energy is called photolysis.
- FAD (Flavin adenine dinucleotide C27H33N9O15P2 ): Any of a group of water soluble pigments that functions as a cofactor (coenzyme) in many metabolic reactions is called FAD.
- Photosystem: photochemical reaction centers consisting chiefly of photosynthetic pigments complexed with protein and occurring in chloroplasts is called photosystem. OR Photosynthetic pigments are organized in the form of clusters, in thylakoid membranes of chloroplasts called photosystems, .
- Photosystem-I : A type of photosystem that absorbs light energy with a wavelength of about 700 nanometers is called photosystem I.
- Photosystem_II: A type of photosystem that absorbs light energy with a wavelength of about 680 nanometers is called photosystem II.
- Pigments: any of a group of compounds that are intensely coloured and are used to colour other materials.
- Glycolysis: Glyco means glucose and lysis means break down. The conversion of glucose into 2 molecules of pyruvic acid in the cytoplasm in the absence of oxygen is called glycolysis.
- AMP: Energy-carrying one phosphorous, adenine and ribose containing molecule found in the cells of all living things.
- Kreb’s cycle: A step in aerobic respiration in which the pyruvic acid molecules are completely oxidized, along with the formation of ATP, NADH and FADH2 is called krebs cycle.
- Pyruvic acid: A 3-carbon acid (C3H4O3) that in carbohydrate metabolism is an important intermediate product formed esp. during glycolysis
- Anaerobic respiration: A type of cellular respiration in which oxygen is not utilized and glucose is incompletely oxydized is called anaerobic respiration.
- Lactic acid fermentation: The type of fermentation in which the end product is Lactic acid is called lactic acid fermentation.
- Alcoholic fermentation: The type of fermentation in which the end product is alcohol is called alcoholic fermentation.
- Light dependent reaction: The phase of photosynthesis that requires the presence of light and that involves photophosphorylation is called light reaction.
- Thylakoid: Any of the membranous disks of lamellae (membranous plats) within plant chloroplasts that are composed of protein and lipid and are the sites of the photochemical reactions of photosynthesis is called thylakoid.
- Autotroph: Organisms that prepare their own food by the process of photosynthesis are called autotrophs.
- Z-Scheme: The whole series of light reactions is called Z-scheme due to its Z-shaped flow chart.
- Limiting factor: Something which , when not sufficient , prevent or slows down a process is called limiting factor.
- Mesophyll: The inner tissues of a leaf , whose cells are green because they contain chloroplasts.
- Metabolism: Metabolism (metabolism means change): Metabolism is the set of biochemical reactions that occur in living organisms in order to maintain life. OR All sorts of chemical reactions that takes place in the body of living organisms is called metabolism.
- ATP: A high energy chemical used in cell as an energy store. OR Energy-carrying Three phosphorous, adenine and ribose containing molecule found in the cells of all living things.
- Stroma: The colorless proteinaceous liquid material of a chloroplast in which the chlorophyll-containing lamellae are embedded is called stroma.
- Photosynthesis: Photosynthesis is the synthesis of glucose from carbon dioxide and water in the presence of sunlight and chlorophyll, with oxygen as a by-product.
- Light Reaction: The phase of photosynthesis that requires the presence of light is called light reaction.
- Dark Reaction or Calvin cycle : Any of a series of chemical reactions in photosynthesis not requiring the presence of light.
- Respiration : The process by which food (glucose) break down and energy is released is called respiration.
- The cellular energy yielding process is called cellular respiration.
- Aerobic Respiration: The cellular respiration occurring in the presence of oxygen is called aerobic respiration.
- Anaerobic Respiration (Fermentation): The type of respiration that occurs in the absence of oxygen is called anaerobic respiration.
- Alcoholic fermentation: The type of fermentation in which the end product is alcohol is called alcoholic fermentation. It occurs in bacteria, yeast etc.
- Lactic acid fermentation:The type of fermentation in which the end product is lactic acid is called lactic acid fermentation. It occurs in skeletal muscles of humans and other animals during extreme physical activities. This also happens in the bacteria present in milk.
- GLYCOLYSIS: Glyco means glucose and lysis means break down. The conversion of glucose into 2 molecules of pyruvic acid in the cytoplasm in the absence of oxygen is called glycolysis.
- Krebs cycle: A step in aerobic respiration in which the pyruvic acid molecules are completely oxidized, along with the formation of ATP, NADH and FADH2 is called krebs cycle.
- Electron transport chain: The sequential transfer of electrons especially by cytochromes in cellular respiration from an oxidizeable substrate to molecular oxygen by a series of oxidation-reduction reactions is called electron transport chain.
- Nutrition: The process in which food is obtained or prepared, absorbed and converted into body substances for growth and energy is called nutrition.
- Nutrients: Nutrients are the elements and compounds that an organism obtains and uses for energy or for the synthesis of new materials.
- Autotrophs or autotrophic organisms: The organisms that prepare their own food by photosynthesis are called autotrophs.
- Heterotrophs or heterotrophic organisms: Organisms that obtain their food from other organisms and used it for growth and energy are called heterotrophs.
- Amylase: An enzyme that act on carbohydrates and degrade it is called amylase.
- Anemia: A disease of blood in which the blood is deficient in red blood cells, hemoglobin, or in total volume is called anemia.
- Appendix: A narrow blind tube usually about three to four inches (8 to 10 centimeters) long that extends from the cecum in the lower right-hand part of the abdomen.
- Assimilation: The incorporation of the products of digestion into the body, for energy, growth and repair of tissues is called assimilation. OR Conversion or incorporation of absorbed simple food into the complex substances constituting the body.
- Balanced diet: Diet which contains all the essential nutrients in correct proportion for the normal growth and development of body is called Balanced diet.
- Bolus: A soft mass of chewed food is called bolus.
- Sphincter: An annular (ring like) muscle surrounding and able to contract or close a bodily opening is called sphincter.
- Cardiac sphincter: The valve between the distal end of esophagus and the stomach is called cardiac sphincter. “OR” the lower esophageal sphincter which residues at the top of stomach is called cardiac sphincter.
- Chyme: The semi fluid mass of partly digested food expelled by the stomach into the duodenum is called chyme.
- Colon: The part of the large intestine that extends from the cecum to the rectum is called colon.
- Constipation: Constipation is a condition where a person experiences hard faeces that are difficult to eliminate.
- Diarrhoea: Diarrhea is a condition in which the sufferer patient has frequent watery, loose bowel movements.
- Dietary fibre: It is the part of food that is indigestible and provide fibers to our body.
- Digestion: Digestion is the process of conversion of complex food components into simple. OR Digestion is the process in which the non-diffusible molecules of food are changed to diffusible ones by the action of enzymes.
- Duodenum: The first part of the small intestine where most of the digestion takes place.
- Emulsification: The break down of large globule (a tiny globe or ball especially of a liquid) into smaller uniformly particles is called emulsification.
- Epiglottis: A thin plate of flexible cartilage in front of the glottis that folds back over and protects the glottis during swallowing is called epiglottis.
- Famine: Famine means the lack of enough food to feed all people living in an area.
- Fat soluble vitamins: Vitamins that are soluble in fats only are called fat soluble vitamins.
- Fertilizer: Any of the chemical or natural substance added to soil or land to increase its fertility is called fertilizer.
- Gastric juice: A thin watery acid digestive fluid secreted by glands in the mucous membrane of the stomach.
- Gastrin: Any of various polypeptide hormones that are secreted by the gastric mucosa and induce secretion of gastric juice.
- Gastric mucosa (mucous membrane): membrane rich in mucous glands on the gut is called Gastric mucosa.
- Goiter: A disease in which the thyroid gland becomes enlarged due to less use of the iodine.
- Ileum: The longest and last part of the small intestine extending between the jejunum and large intestine where food is completely digested and absorbed is called ileum.
- Intestinal juice: clear to pale yellow, watery secretion composed of hormones, digestive enzymes, mucus, and neutralizing substances released from the glands of small and large intestine.
- Jejunum: The thicker waled part of the small intestine between the duodenum and ileum.
- Kwashiorkor: severe malnutrition in infants and children esp. of impoverished regions caused by a diet low in protein.
- Lacteal: Any of the lymphatic vessels arising from the villi of the small intestine and conveying chyle (Milky fat like digestive juice) to the thoracic duct.
- Laxatives: Medicines that producing bowel movements and relieving constipation.
- Lipase: Enzymes that act on lipids and digest them are called lipases.
- Liver : A large very vascular glandular organ of vertebrates that secretes bile is called liver.
- Malnutrition: Problems related to nutrition are grouped as malnutrition. OR Lack of proper nutrition is called malnutrition.
- Marasmus: A condition of chronic undernourishment occurring esp. in children and usu. caused by a diet deficient in calories and proteins is called marasmus.
- Mineral deficiency diseases: Diseases resulting from the deficiency of a mineral are called mineral deficiency diseases.
- Oesphagus: A muscular large tube of digestive system in between the stomach and pharynx is called esophagus.
- Oral cavity: The cavity of the mouth is called oral cavity or buccal cavity.
- Over-intake of nutrients (OIN): Over-intake of nutrients (OIN) is a form of malnutrition in which more nutrients are taken than the amounts required for normal growth, development and metabolism.
- Pancreas: Large gland located in the abdomen near the stomach which produces pancreatic juice for digestion and the hormones insulin and glucagon.
- Pancreatic juice: A clear alkaline secretion of pancreatic enzymes (as trypsin and lipase) secrete by pancrea.
- Pepsin: A protease enzyme of the stomach that breaks down most proteins to polypeptides is known as pepsin.
- Pepsinogen: A granular zymogen (inactive protein) of the gastric glands that is readily converted into pepsin in a slightly acid medium.
- Pertistalsis : The involutary wavy movement of the esophagus and small intestine is called peristalsis.
- Pharynx : The muscular tubular passage of the vertebrate digestive and respiratory tracts extending from the back of the nasal cavity and mouth to the esophagus.
- Protein energy malnutrition: Protein-energy malnutrition means inadequate availability or absorption of energy and proteins in the body.
- Sphincter: An annular muscle surrounding and able to contract or close a bodily opening is called sphincter.
- SPHINCTERS OF STOMACH: The opening of the stomach which are guarded by muscles are called sphincters.
- Cardiac sphincter : Sphincter in between stomach and esophagus.
- Caecum (cecum): The first pouch or large tube like part of the large intestine that recieve undigested food materials from the small intestine is called cecum.
- Pylorus: The muscular opening from the vertebrate stomach into the intestine is called pylorus.
Pyloric sphincter: A ring of smooth muscle fibers around the opening of the stomach into the duodenum is called pyloric sphincter. OR Sphincter in between stomach and small intestine.
- Rectum : The terminal part of the intestine from the sigmoid colon to the anus is called rectum.
- Saliva : Fluid secreted by glands in the mouth which moistens ,softens and semi-digest food is called “OR” A slightly alkaline secretion of water, mucin, protein, salts, and often a starch-splitting enzyme (as ptyalin) that is secreted into the mouth by salivary glands, lubricates ingested food, and often begins the breakdown of starches.
- Starvation: Wasting away of the body tissues or damaging of the organs due to unavailability of food or improper absorption.
- Stomach: The dilated part of the alimentary canal where most of the digestion takes place is called stomach.
- Swallowing : The taking in of food through the mouth and esophagus into the stomach is called swallowing.
- Trace minerals: Minerals that are required in very less amount to living organisms are called trace minerals.
- Trypsin: A proteolytic enzyme that is most active in a slightly alkaline medium.
- Ulcer : Ulcer (peptic ulcer) is a sore in the inner wall of gut (in oesophagus, duodenum or stomach). Ulcer of stomach is called gastric ulcer.
- Peptic: Any part of the body that normally has an acidic lumen
- Lumen : is the inside space of a tubular structure, such as an artery, intestine or intestine.
- Villus (villi) : Minute hair like projections which cover the lining of the small intestine ; provide surface area for absorption.
- Vitamins : Organic substances which are essential in small amounts to regulate the metabolism and maintain the immune system are called vitamins.
- Water soluble vitamins: Vitamins that are only soluble in water are called water soluble vitamins.
- Fertilizer: Any of the chemical or natural substance added to soil or land to increase its fertility is called fertilizer.
- Inorganic fertilizers : inorganic fertilizer is comprised of synthetic, artificial ingredients manufactured and ready to use on plants.
- Organic Fertilizers:Fertilizers obtained from plants and animals or their decaying matter are organic fertilizes.
- Carbohydrates: They are organic compounds composed of polyhydroxy aldehydes and polyhydroxy ketone.
- Lipids: Organic compounds composed of fatty acids and glycerol are called lipids.
- Saturated fatty acids: Saturated fatty acids have all of their carbon atoms singly bonded to other carbon or hydrogen atoms.
- Unsaturated fatty acids: Unsaturated fatty acids have some of their carbon atoms double-bonded in place of a hydrogen atom.
- Proteins: The biopolymers of amino acids are called proteins.
- MINERALS: Minerals are inorganic elements that originate in the Earth and cannot be made in body.
- Dietary Fiber (Roughage) it is the part of food that is indigestable and provide fibers to our body.
- Balance Diet: Diet which contains all the essential nutrients in correct proportion for the normal growth and development of body is called Balanced diet.
- Mineral deficiency diseases (MDD): Diseases resulting from the deficiency of a mineral are called mineral deficiency diseases.
- Over-intake of nutrients (OIN) : Over-intake of nutrients (OIN) is a form of malnutrition in which more nutrients are taken than the amounts required for normal growth, development and metabolism.
- Drought : A drought is a period of time when there is not enough water to support agricultural and human needs.
- Flooding : It occurs due to more than normal rainfall or due to weak water distribution system.
- Alimentary canal : The digestive system of human consists of a long tube that extends from mouth to anus.
- Mastication or chewing: The grinding of food by teeth is called mastication.
- Oral cavity: The space behind mouth is called oral cavity.
- Stomach : The J shaped dilated part of the alimentary canal is called stomach.
- Colon: It is the second part of large intestine that is responsible for absorption of water into the blood.
- Rectum: It is the third and last part of the small intestine where faeces are temporarily stored.
- Ulcer : Ulcer (peptic ulcer) is a sore in the inner wall of gut (in oesophagus, duodenum or stomach). Ulcer of stomach is called gastric ulcer.
- Systole: The contraction or period of contraction of the heart, specially of the ventricles, during which blood is forced into the aorta and pulmonary artery is called systole.
- Diastole: The normal dilation of the heart during which heart refill with blood is called diastole.
- Blood group antigens : Antigens on the membranes of red blood cells.
- ABO system: A type of blood group system in which bloods are grouped on the basis of presence or absence of antigen A and B.
- Agglutination: The formation of aggregate (clusture) of antigen and antibody is called agglutination.
- Albumin: a type of protein that is soluble in water and is coagulable by heat.Serum albumin is a component of blood serum. Egg albumin is a component of egg.
- Angina pectoris: Chest pain due to an inadequate supply of oxygen to the heart muscles is called angina pectoris.
- Anti-A antibody: A type of antibody present in blood against the antigen B is called Anti-A antibody.
- Anti-B antibody: A type of antibody present in blood against the antigen A is called Anti-B antibody.
- Antigen : Foreign invaders in the body that stimulates the production of antibody.
- Antigen A : An antigen present on the membrane of erythrocytes responsible for blood group A is called antigen A.
- Antigen B: A sugar containing antigen present on red blood cells against anti-A-antibody responsible for blood group B is called Antigen B.
- Anti-Rh antibody: An antibody present on the membrane surface of red blood cells of organisms having Rh-negative blood group.
- Aorta: The great arterial trunk that carries blood from the heart to be distributed by branch arteries through the body is called aorta. OR The largest artery in the body is called aorta.
- Aortic arch: The curved transverse part of the aorta that connects the ascending aorta with the descending aorta is called aortic arch.
- Arteriole: Any of the small terminal twigs of an artery that ends in capillaries are called arterioles.
- Arteriosclerosis: A disease in which arteries becomes harden due to accumulation of calcium is called arteriosclerosis.
- Ascending aorta: The first section of the aorta , which starts from the left ventricle of the heart and extends to the aortic arch is called ascending aorta. The right and left coronary arteries that supply blood to the heart muscles arise from the ascending aorta.
- Dorsal aorta or descending aorta : The main trunk of the aorta carrying blood from the left side of heart to the arteries of all limbs and organs except the lungs is called dorsal aorta.
- Lymphocytes : A type of White blood cells which attack pathogens is called lymphocytes.
- Lymphogenous: (lymphpo means related to lymph and genous means origin). Any material produce from lymph or in lymphatic vessels or spread through lymph is termed as lymphogenous.
- Lymphogenous cells: Cells of the lymphatic system are called lymphogenous cells.
- Megakaryocytes : A large cell that has a lobulated nucleus, is found especially in the bone marrow, and is the source of blood platelets.
- Monocytes :A large white blood cell with finely granulated chromatin dispersed throughout the nucleus that is formed in the bone marrow.
- Myocardial Infarction Heart attack: A disease of heart in which blood supply to a part of heart is interrupted and leads the death of heart muscles.
- Neutrophils: The type of white blood cells that destroy small solid harmful particles by phagocytosis are called neutrophils.
- Pericardial fluid; The fluid in between the heart walls and pericardium is called pericardial fluid.
- Pericardium: The heart is enclosed in tough, fibrous and extensible membrane called
- Pericycle: A thin layer of parenchymatous or sclerenchymatous cells that surrounds the vascular tissues in most vascular plants is called pericycle.
- Phloem : Compound tissues through which food is transported in a plant is called phloem.
- Plasma : Liquid non cellular part of the blood is called plasma.
- Platelets: white blood cells fragments which circulate in the blood and assist in clotting are called platelets.
- Pulmonary artery: The artery that carries deoxygenated blood to lungs is called pulmonary artery.
- Pulmonary circulation: The pathway on which deoxygenated blood is carried from heart to lungs and in return oxygenated blood is carried from lungs to heart is called pulmonary circulation or pulmonary circuit.
- Pulmonary vein: A vein that carries oxygenated blood from lungs to heart is called pulmonary vein.
- Pulse: The regular expansion of an artery caused by the ejection of blood into the arterial system by the contractions of the heart is called pulse.
- “OR”The edible seeds of various crops (as peas, beans) of the legume family is called pulse.
- Arteries : The thick walled blood vessels which carry blood away from the heart.
- Atherosclerosis: An arteriosclerosis characterized by atheromatous deposits (an abnormal fatty deposits in an artery) in and fibrosis(increase in fibrous tissues) of the inner layer of the arteries is called atherosclerosis.
- Atrial systole :The contraction of the heart through which blood is pumped to all the parts of the body is called systole.
- Atrium: Either of the chambers of the heart that receives blood from the veins and forces it into the ventricle or ventricles is called atrium (auricle).
- B lymphocytes: any of the lymphocytes that have antigen-binding antibody molecules on the surface, that comprise the antibody-secreting plasma cells when mature.
- Basophils: The type of white blood cells that prevent clotting are called basophills.
- Bicuspid valve OR Mitral valve: A cardiac valve consisting of two triangular flaps which allow only unidirectional blood flow from the left atrium to the ventricle is called bicuspid valve.
- Blood group system; A system in which blood are grouped into various categories based on presence or absence of specific antigens.
- Capillary: Extremely narrow tubes which carries blood around our tissues.
- Cardiac cycle: The alternating contraction and relaxation heart makes a cycle that carries blood towards and away from the heart is called cardiac cycle.
- Cardiovascular system: A system involving blood and associated vessels that circulates blood in all parts of the body is called cardiovascular system.
- Cohesion-tension theory: Cohesion tention theory explains how water move from roots to the tip of the plant. According to this theory the main mechanism involve in this process is transpiration pull. That is developed due to the attractive forces between the molecules.
- Coronary artery: Either of two arteries that arise one from the left and one from the right side of the aorta is called coronary artery.
- Cortex: The typically parenchymatous layer of tissues external to the vascular tissue and internal to the epidermal tissues of a green plant is called cortex.
- Red Blood Cells: Cells which contain haemoglobin and carry oxygen are called RBC.
- Rh factors (Rhesus factor) : A proteinacious antigen responsible for the Rh blood group is called Rh factor. It was first discovered in rhesus monkey so named as rhesus.
- Rh-blood group system: A system in which blood are arranged into groups on the basis of presence or absence of rhesus (RH) antigen.
- Root hair : A filamentous extension of an epidermal cell near the tip of a root that functions in absorption of water and minerals.
- Semilunar valve: The crescent shaped valve in between the heart and aorta and in between the heart and the pulmonary artery is called semilunar valve.
- Stoma (Plural ‘stomata’): Thin pores in the epidermis of a leaf that controle water loss and gas exchange by opening and closing.
- Systemic circulation: The pathway on which oxygenated blood is carried from heart to body tissues and in return deoxygenated blood is carried from body tissues to heart is called systemic circulation or systemic circuit.
- T lymphocytes: A type of leukocytes (white blood cells) that originates in the bone marrow, matures in thymus and is an essential part of body defense system.
- Thalassaemia: A genetic blood disorder in which oxygen cannot properly transported to body parts due to mutation in the gene of haemoglobin.
- Thrombocytes: Fragments of white blood cells that are involved in blood clotting are called thrombocytes or platelets.
- Thrombus: (Thrombus means clot) A clot of blood formed within a blood vessel and remaining attached to its place of origin. Or a blood clot that forms in a vein is called thrombus.
- Transpiration: The loss of water from the aerial parts of the plant by evaporation is called transpiration.
- Tricuspid valve: A valve of three flaps that prevents reflux of blood from the right ventricle to the right atrium.
- Veins: Thin walled tubes which carry blood back to the heart are called veins.
- Vena cava: Any of the large veins by which the blood is returned to the right atrium of the heart.
- Embolus; (plural emboli) : An abnormal particle circulating in the blood usually blood clot or air bubble that travels in the blood vessels. It usually blocks the blood vessels.
- Endodermis: The innermost tissue of the cortex in many roots and stems is called endodermis.
- Eosinophil: Type of white blood cells that break inflammatory substances and kill parasites is called eosinophil.
- Erythrocyte: Hemoglobin-containing blood cells that carry oxygen to the tissues and are responsible for the red color of vertebrate blood are called erythrocytes or red blood cells.
- Fibrin: A white insoluble fibrous protein formed from fibrinogen by the action of thrombin protein especially in the clotting of blood.
- Fibrinogen: A plasma protein that is produced in the liver and is converted into fibrin during blood clot formation.
- Granulocytes: Type of white blood cells that have granular cytoplasm is called granulocytes.
- Guard cell: Bean shaped cells which control the opening and closing of stomata are called guard cells.
- Haemoglobin: The red protein found in red blood cells that transport oxygen is called haemoglobin.
- Heart rate: Heart rate is the number of times the heart beats per minute.
- Lenticels: pores on the stem of a woody plant that allows gas exchanges between the atmosphere and the internal tissues. These are located on woody parts of the plant such as stem and branches.
- Leucocytes: The colourless large irregular shaped cells involved in the defense system of the body are called leukocytes or white blood cells.
- Leukaemia; An acute or chronic disease in humans and other warm-blooded animals characterized by an abnormal increase in the number of white blood cells in the tissues and often in the blood.
- Ventricle: Ventricles are thick walled chambers that pump the
- Venule: The minute veins connecting the capillaries with the larger systemic veins are called venules.
- White Blood Cells: The colourless large irregular shaped cells involved in the defense system of the body are called leukocytes or white blood cells.
- Wilting: The loss of rigidity of a non woody part of a plant is called wilting.
- Xylem: Compound tissues which transports water and minerals to upper parts plant are called xylem.
- Transpiration: • The loss of water in the form of vapours from aerial parts of the plants, especially through stomata is called
- Transpiration pull: The suction force that pulls water to upper parts of the plant is called transpiration pull.
- Transpiration stream : Transpiration streamis the unbroken stream of water and solutes which is taken up by the roots and transported via the xylem vessels to the leaves where it evaporates.
- Stomatal transpiration: Transpiration through stomata is called Stomatal transpiration.
- Cuticular transpiration: Transpiration takes place through cuticle is called cuticular transpiration.
- Lenticular transpiration: Transpiration through lenticles is called lenticular transpiration.
- Translocation: The transport of food in plants is called translocation.
- Lymphatic system: A complex network of vessels, tissues and organs that maintains the fluid balance in the body is called Lymphatic system.
- Circulatory system: organ system that conveys blood through vessels to and from all parts of the body, carrying nutrients and oxygen to tissues and removing carbon dioxide and other wastes is called circulatory system.
- BLOOD: Blood is a specialized body fluid (connective tissues) that is composed of a liquid called blood plasma and blood cells. “OR”
- A reddish fluid in animals that contain water, cell bodies and other substances and is used for transport of materials is called blood.
- BLOOD PLASMA : Plasma is primarily water in which proteins, salts, metabolites and wastes are dissolved.
- BLOOD CELLS and cell-like bodies:
- These include red blood cells (erythrocytes), white blood cells (leukocytes) and platelets (thrombocytes).
- Leukaemia (blood cancer) Leukaemia is the production of great number of immature and abnormal white blood cells.
- Thalassaemia (g. thalassa = sea; haem = blood) :Thalassemia (Greek: “sea blood”) is so called because it was first discovered among peoples around the Mediterranean Sea, among whom its incidence is high. Any of a group of hereditary haemolytic diseases caused by faulty or abnormal haemoglobin synthesis.
- Blood group systems: Blood group systems are a classification of blood based on the presence or absence of antigens on the surface of red blood cells.
- Antigen: An antigen is a molecule that can stimulate an immune response (antibody production etc.).
- HUMAN HEART: Human heart is muscular contractile organ responsible for pumping blood through blood vessels by repeated contractions.
- Atria: Atria are thin walled chambers of the heart that recieved the blood.
- Ventricles: Ventricles are thick walled chambers of the heart that pump the blood.
- Systole: The period of ventricular contraction is called
- Diastole: The period of ventricular relaxation is called
- Cardiac cycle: The alternating contraction and relaxation of the heart chambers is called the cardiac cycle.
- Pulmonary Circulation: The pathway on which deoxygenated blood is carried from heart to lungs and in return oxygenated blood is carried from lungs to heart is called pulmonary circulation or pulmonary circuit.
- Systemic circulation: The pathway on which oxygenated blood is carried from heart to body tissues and in return deoxygenated blood is carried from body tissues to heart is called systemic circulation or systemic circuit.
- Heart Beat: one complete cycle of contraction and relaxation of heart is termed as heart beat.
- Heart rate and Pulse rate : Heart rate is the number of times the heart beats per minute.
- Arteries: The vessels that carry blood from heart to all parts of the body are
- called arterie.
- Capillaries: Arteries on reaching to different body parts divides into very small vessels
- called capillaries.
- Veins: -The vessels that bring blood back from all parts of body to heart are called veins.
- CARDIOVASCULAR DISORDERS: The diseases that involve the heart or blood vessels are collectively called cardiovascular disorders.
- Atherosclerosis: A disease of narrowing of the blood arteries is called atherosclerosis.
- Arteriosclerosis: The hardening of the blood arteries is called Arteriosclerosis.
- Myocardial Infraction OR Heart Attack: The term myocardial infarction is derived from myocardium (the heart muscle) and infarction (tissue death) : It is a condition when the blood supply to a part of heart is interrupted and leads to the death of heart muscles.
- Lenticles: Pores on the stem of a woody plant that allows gas exchanges between the atmosphere and the internal tissues.
- Sources: Sources are parts of plants where fixation of carbon dioxide occurs and food is formed.
Sinks: Sinks are the parts where the foods are stored and us
Abiotic: The non-living components of the environment like water, sunlight, soil, heat etc.
Acid rain: The rain containing sulphuric acid and nitric acid; with pH range of 3 to 6
Acromegaly: Abnormal growth due to excessive production of growth hormone after growing age; the internal organs and body extremities alone grow large and affected persons have large hands, feet and jawbones.
Acrosome: Cap-like head of sperm cell which helps it in penetrating the egg cell.
Addictive drug: The drug which makes a person dependent on it, or addicted
Adrenal cortex: The outer portion of adrenal gland; secretes corticosteroids
Adrenal medulla: The inner portion of adrenal gland; secrets epinephrine or adrenaline
Adrenaline: Epinephrine; a hormone that prepares body to overcome emergency situations; a neurotransmitter produced by some nerve cells
Allele: The alternative form of a gene
Alternation of generations: In plants, the phenomenon in which the sporophyte and gametophyte generations alternate with each other
Alveolar duct: Fine tubules at the end of bronchioles; open into alveoli
Alveolus: A sac-like structure present next to the alveolar duct in lungs
Ammonification: The decomposition of protein of dead plants and animals, and nitrogenous wastes to ammonia by ammonifying bacteria
Analgesic: The medicines that reduce pain
Androecium: The male reproductive whorl of the flower; consists of stamens
Anther: The sac-like structure of a stamen in which pollen grains are produced
Antibiotics: The medicines which inhibit or kill bacteria
Antidiuretic hormone: The hormone of the posterior pituitary; promotes the reabsorption of water in renal tubules
Appendicular Skeleton: The division of the skeleton that includes arms, hands, legs, feet pectoral girdle and pelvic girdle
Aqueous humour: The fluid present in the anterior chamber of the eye i.e. between the cornea and the iris
Arthritis: Terms used for the inflammation in joints
Artificial selection: Selective breeding; intentional breeding between individuals for certain traits, or combination of traits
Aspirin: Acetaminophen; A pain-killer medicine
Asthma: An inflammation of the bronchi that causes swelling and narrowing of the airways
Atmospheric nitrogen fixation: The conversion of atmospheric gaseous nitrogen to nitrates by thunderstorms and lightning
Auditory canal: The part of the external ear; ends at ear drum
Autonomic Nervous System: Part of the peripheral nervous system; consists of motor neurons that send signals to the cardiac muscles, smooth muscle and glands; generally without conscious control
Axial skeleton: The division of the skeleton that includes the skull, vertebral column, ribs and breastbone
Axon: A long, thin fibre that carries nerve impulse away from the cell body of a neuron
Bactericidal: The antibiotics that work by killing bacteria
Bacteriophages: The viruses that attack bacteria
Bacteriostatic: The antibiotics that work by stopping bacteria multiplying
Ball-and-socket joint: The joint that allows movement in all directions e.g. hip and shoulder joints
Batch fermentation process: The discontinuous fermentation process, divided into batches
Biceps: A flexor muscle on the front of the upper arm bone
Binary fission: Division into two; the simplest method of asexual reproduction in prokaryotes and many unicellular eukaryotes
Biogeochemical Cycle: The cyclic pathway through which chemical elements move from environment to organisms and back to the environment
Biological nitrogen fixation: The conversion of gaseous nitrogen into nitrates by living organisms
Biosphere: The last level of ecological organization; all the ecosystems of the world together form the biosphere
Biotechnology: The use of living organisms in systems or processes for the manufacture of useful products or for services for humankind
Biotic: The living components of the environment; include producers, consumers and decomposers
Bone: Hard connective tissue; moves, supports and protects the various organs of the body
Bowman’s capsule: Part of nephron: cup-shaped structure enclosing the glomerulus
Breathing: The process through which animals take air in their bodies to get oxygen and then give out the air for getting rid of carbon dioxide
Breeds: The animals which are bred through artificial selection
Bronchioles: Fine tubules formed by the division of the bronchi
Bronchitis: Inflammation in the bronchi or bronchioles
Bronchus: The part of air passageway; formed by the division of the trachea
Budding: A type of asexual reproduction in which a bud develops as a small outgrowth on parent’s body and forms the new individual
Bulbs: Underground vertical shoots which have modified leaves
Calyx: The outer whorl of flowers; consists of sepals
Carbon cycle: The biogeochemical cycle in which carbon flows between organisms and the environment
Cardiotonic: Medicines for giving strength to heart muscles
Carnivores: The consumers which eat only animal flesh
Carpel: Part of the gynoecium of the flower; consists of stigma, style and ovary
Cartilage: The connective tissue that makes part of the human skeleton
Cell body: The part of the nerve cell that contains nucleus
Central nervous system: The part of the nervous system consisting of brain and spinal cord
Cephalosporin: A group of antibiotics; interfere with synthesis of the bacterial cell wall
Cerebellum: The part of the hindbrain; controls muscle movements
Cerebral hemispheres: The divisions of the cerebrum of the brain
Cerebrospinal fluid: The fluid in the ventricles of the brain and in the central canal of the spinal cord
Cerebrum: The largest part of the forebrain; controls many sensory and motor functions
Cervix: In female reproductive system, the part which separates uterus from the vagina
Chondrocyte: The cells present in the cartilage
Chromatin: The chemical material that make the structure of the chromosome
Cloning: Method of asexual reproduction in which identical offsprings are produced from a vegetative tissue or cell of the parent
Cochlea: The part of the inner ear; consists of three ducts wrapped in the form of a coiled tube; contains sound receptors
Co-dominance: The situation where two allele of a gene pair express their traits independently instead of showing a dominant-recessive relationship
Collecting duct: The tubes into which the renal tubules of nephrons open
Colour blindness: Genetic disorders in which person fails to recognize the basic colours
Commensalism: A type of symbiosis in which one of the partners gets benefit while the other is neither benefited nor harmed
Compact bone: The hard outer layer of bones
Cones: The photosensitive cells in the retina of the eye; sensitive to bright light and so distinguish different colours
Consumer: The part of the biotic components of the ecosystem that consists of animals
Continuous fermentation process: The fermentation in which substrate is added to the fermenter continuously, at a fixed rate
Corm: Short, swollen underground stem; has bud(s) at the top; gives rise to new plants by vegetative propagation
Cornea: The transparent part of sclera that forms in the front of the eye through which light enters
Corolla: The second whorl of flower, consisting of petals
Cotyledon: A modified leaf present in seeds; often gives nourishment to the developing seedling
Cowper’s gland: An accessory gland in rabbits male reproductive system; provides lubrication to the ducts
Cranial bones: The bone of the cranium
Cranial nerves: Nerves that arise from or lead to the brain
Cultivars: The plants which are bred through artificial selection
Cutting: Artificial vegetative propagation in which cuttings are taken from stem or root of parent and are placed in soil
Decomposer: An organism which decomposes the dead bodies and dead matter
Deforestation: Clearing of forests by natural causes or by humans
Dendrites: Short, branched projections of neuron’s cell body; transmits nerve impulse towards cell body
Denitrification: The conversion of nitrites and nitrates into nitrogen gas
Diabetes mellitus: More than normal level of glucose in blood; a condition caused by insufficient concentration of insulin in blood
Dialysis: The cleaning of blood (removing nitrogenous wastes and extra water) by artificial ways
Dialyzer: The apparatus used for haemodialysis
Diaphragm: The muscular structure that forms the floor of the chest cavity;
present below lungs
Dihybrid cross: A genetic cross in which two pairs of contrasting traits are studied
Dominant trait: The trait that appears in the offspring of a cross between two homozygous individuals showing contrasting forms of the trait
Drug: Any substance that, when absorbed into the body of a living organism, alters normal body function
Dwarfism: Less than normal body growth; a condition caused when growth hormone is insufficient during the growing age
Ear drum: Tympanic membrane; A membrane stretched across the inner end of the auditory canal of the ear
Ecological pyramid: A representation of the number of individuals or amount of biomass or energy present in various trophic levels of a food chain
Effectors: The parts of the coordination system that respond when stimulated by nerve impulses or hormones
Emphysema: A disease in which the walls of the alveoli are destroyed
Endocrine gland: A ductless gland; produces and secretes hormones
Endosperm nucleus: In the female gametophyte, the triploid nucleus formed by the fusion of sperm and the fusion nucleus
Endosperm tissue: The tissues that develops from endosperm nucleus; often serves as a food supply for developing embryo
Endospore: The spore formed inside the bacterial cell
Environment: The sum total of physical (abiotic) and biotic conditions which influence the organism
Epicotyl: The embryonic stem above the point of attachment of the cotyledon(s)
Epididimys: A storage area for sperms on the upper part of the testes
Epigeal germination: A type of seed germination in which the hypocotyl elongates and forms a hook, pulling the cotyledons above the ground
Epilepsy: A nervous disorder characterized by recurrent unprovoked seizures (convulsions)
Epinephrine: See Adrenaline
Estrogen: A hormone secreted by the ovaries; promotes development of female secondary sex characteristics and regulates the reproductive cycle
Eustachian tube: The tube between middle ear and the nasal cavity that equalizes the pressure on both sides of the ear drum
Eutrophication: The enrichment of water with inorganic nutrients; the nutrients promote the growth of algae and it leads to increase in the number of the decomposers and depletion of oxygen
Excretion: The process by which the metabolic wastes are removed from the body
Exhalation: The phase of breathing in which air is expelled from the lungs
Exocrine gland: A gland that discharges its secretion into a duct
Extensor: A muscle that extends a joint.
Fallopian tube: a part of the female reproductive system; receives egg cell discharged from the ovary
Feedback mechanisms: The mechanisms to control certain functions; one of the products of a pathway are used, usually the end product, to control the activity of the pathway
Fermentation: The process in which there is incomplete oxidation-reduction of the organic substrate (glucose)
Fermenter: A device that provides optimum environment in which organisms can grow to produce biomass and to form the product.
Fertilization: The fusion of male and female gametes to form a zygote
Fibrous cartilage: The cartilage that has large number of fibres in the matrix e.g. the cartilage in intervertebral disc
Flexor: A muscle that bends a joint
Follicle: A structure in the ovary in which the mature egg develops
Food chain: The series of organisms in an ecosystem, in which an organism eats the preceding one and is eaten by the next one
Food web: A network of interconnected food chains; has a number of feeding connections amongst different organisms of a community
Forebrain: The part of the brain; includes cerebrum, thalamus and hypothalamus
Fragmentation: A type of asexual reproduction in which the animal breaks up into many pieces and each piece develops into a mature animal
Fusion nucleus: A part of the female gametophyte in plants; formed by the fusion of two nuclei; gives rise to endosperm nucleus when fertilized by a sperm
Gametogenesis: The process of the formation of gametes
Gametophyte: The haploid generation in plant life cycle; produces gametes
Ganglion: The aggregation of the cell bodies of neurons
Gaseous exchange: Taking in and giving out of gas (oxygen and carbon dioxide) by organism
Gene: Unit of inheritance; consists of the length of DNA that contains specific instructions for the synthesis of a protein molecule
Genetically Modified Organism: The organism in which DNA (gene) from some other organism has been transferred
Genotype: The specific combination of genes in an individual; may be homozygous or heterozygous
Germination: The process by which a seed embryo develops into a seedling
Gigantism: The condition due to excessively production of growth hormone during the growing age; leads to very tall and overweight persons
Global Warming: Increase in the temperature of the Earth; due to the addition of greenhouse gases in atmosphere, which do not allow solar radiations to reflect back into the space
Glomerular filtrate: The material that passes from glomerulus into the Bowman’s capsule
Glomerulus: The network of capillaries in the nephron of kidney
Glucagon: The hormone secreted by the islets of Langerhan; increases the blood glucose level
Gout: A type of arthritis; characterised by the accumulation of uric acid crystals in the moveable joints
Grey matter: The nervous tissue containing cell bodies and non-myelinated processes of the neurons
Guttation: Appearance of drops of xylem sap on the tips or edges of leaves
Hallucinogen: Drug that causes changes in perception, thought, emotion and consciousness
Haemodialysis: The dialysis in which patient’s blood is pumped through the apparatus called dialyzer for cleaning
Heroin: A commonly abused narcotic; derived from morphine; affects the central nervous system and causes drowsiness, disorientation, hypotension etc.
Heterozygous: The genotype that has two different alleles of a trait
Hilum: A scar on the seed coat; the point where the seed is attached to the ovary wall
Hilus: A depression near the centre of the concave area of the kidney; the area through which the ureter, blood and lymphatic vessels and nerves enter/leave the kidney
Hindbrain: The part of the brain consisting of cerebellum, medulla oblongata and pons
Hinge joint: A joint that permits movement of bones in one plane e.g. elbow and knee joints
Histone: The protein present in the structure of chromosome
Homeostasis: The maintenance of a constant internal environment in response to environmental changes
Hormone: A substance that is secreted by an endocrine gland directly into blood and that produces a specific effect on a particular tissue
Hyaline cartilage: The cartilage that has collagen fibres in its matrix; found covering the ends of the long bones, in the nose, larynx, trachea and bronchial tubes
Hyoid bone: The bone present in neck
Hypermetropia: The condition in which a person is not able to see near objects clearly; happens when the eyeball shortens and image is formed behind the retina
Hyperthyroidism: The over-production
of thyroxin; result in increase in energy production, increased heart-beat, frequent sweating and shivering of hands
Hypocotyl: The embryonic stem below the point of attachment of cotyledon
Hypogeal germination: A type of seed germination in which the epicotyl elongates and forms the hook while the cotyledons stay underground
Hypothalamus: The part of the forebrain below the thalamus; controls body temperature, blood pressure and emotion
Hypothyroidism: The under-production of thyroxin; results in low energy production and slowing down of heart-beat
Incomplete dominance: A type of inheritance in which neither of the pair of contrasting alleles is dominant over the other and the heterozygous individual is intermediate in phenotype
Inhalation: The phase of breathing in which air is drawn into the lungs
Inheritance: The transmission of characteristics from parents to offspring
Insertion: The end of the muscle that is attached with a moveable bone
Insulin: The hormone produced by the Islets of Langerhans; lowers the blood glucose level
Interneurons: The neurons present in the brain and spinal cord
Interspecific interactions: Interactions between the members of the different species
Intraspecific interactions: Interactions between the members of the same species
Iodopsin: A pigment present in the cones of the retina
Islets of Langerhans: Groups of endocrine cells present in pancreas;secrete hormones insulin and glucagon
Iris: A muscular ring formed by the bending of the choroid behind the cornea of the eye
Kidney failure: A complete or near complete failure of the kidneys to excrete wastes and to regulate water and salts
Kidney stone: The deposits of large chemicals such as calcium oxalate, calcium and ammonium phosphate, uric acid, cystine etc. present in kidneys, ureter or bladder; cannot pass in the urine
Lacuna: The fluid filled space in bone and cartilage, where their cells are present
Larynx: The part of the air passageway between pharynx and the trachea
Lenticels: Pores in the bark of wooding stems and mature roots
Ligament: Strong but flexible connective tissue that joins one bone to bone at the joints
Lithotripsy: Treatment for removing kidney stones; non-electrical shock waves are bombarded on the stones to break them
Locus: Plural Loci; The locations or positions of genes on chromosomes
Loop of Henle: The U-shaped portion of the renal tubule of nephron
Macrospore: Haploid cell produced in the ovule; divides mitotically and produces the female gametophyte
Marijuana: A hallucinogen and addictive drug; obtained from the flowers, stems, and leaves of the marijuana plant
Medicinal drug: Any chemical substance intended for use in the medical diagnosis, cure, treatment, or prevention of disease
Medulla oblongata: Part of the hindbrain; on the top of the spinal cord; controls breathing, heart rate, blood of the retina
Narcotics: Strong painkiller drugs; also used as addictive drugs; commonly abused narcotics include heroin, morphine, methadone etc
Nasal cavity: Hollow space in the nose; opens to the outside through nostrils; divided into two portions by a wall
Natural resources: The resources on Earth, which provide everything that humans use or consume
Natural selection: The process in which organisms with favourable variations survive and produce more offspring than less well-adapted organisms
Nephron: The functional unit of kidneys
Nerve: The union of several axons that are enveloped by a covering made of lipid
Neuron: Nerve cell; the unit of the nervous system; able to conduct nerve impulses
Nitrification: The oxidation of ammonia to nitrites and nitrates by the nitrifying bacteria
Nitrogen cycle: The flow of nitrogen between environment and the organisms
Nitrogen fixation: Conversion of nitrogen into nitrates
Nodes of Ranvier: The non-myelinated points between the areas of myelin on the axons of neurons
Non-renewable resource: A resource that is formed over very long periods; the rate of formation is extremely slow so cannot be replaced; e.g. minerals and fossil fuels
Nostril: The openings of the nasal cavity
Nucleosome: The structure formed by the wrapping of DNA around histone proteins
Olfactory bulbs: The anterior parts of the cerebral hemispheres; receive impulses from the olfactory nerves and create the sensation of smell
Oogenesis: The formation of ovum (egg cell)
Oogonium: (Plural Oogonia): The diplod cells in the follicles of the ovary; produce diploid primary oocytes during oogenesis
Optic disc: Blind spot; a point on the retina of the eye where the optic nerve enters the retina; no photosensitive cells exist at this point
Organic evolution: Biological evolution: The modification of characteristics in the species or populations of organisms during their descent, generation by generation
Origin: The end of the muscle that is attached with a immoveable bone
Osmoregulation: The regulation of water content in body fluids
Osteoarthritis: Inflammation in joints due to degeneration in the cartilage present at the joints or due to decreased lubricant production at the joints
Osteocyte: The mature bone cells
Osteoporosis: A bone disease in adults, especially in old age; there is a decrease in the density of bones due to loss of calcium and phosphorus
Oval window: The membrane which separates the middle ear from the inner ear
Ovary: The female gonad; produces egg cells and female sex hormones
Overpopulation: Increase in population beyond the carrying capacity of an area or environment
Ovule: In seed plants, a structure present in the ovary; contains macrospore that develops into female gametophyte; ovule develops into seed after fertilization
Ozone: The O3 gas; also present in theupper layer of the atmosphere where it absorbs the ultraviolet rays present in the sun’s radiation
Oxytocin: The hormone secreted by the posterior pituitary; stimulates the contraction of uterus walls in females for child birth; necessary
for ejection of milk from the breasts
Papillary ducts: The ducts formed by the joining of many collecting ducts; open into renal pelvis
Paralysis: Complete loss of function by one or more muscle groups due to damage in the nervous system
Parasitism: A type of interspecific interaction in which smaller partner (parasite) derives food and shelter from the body of larger partner (host) and harms the host
Parasympathetic nervous system: Part of the autonomic nervous system; works when there is little or no stress and slows down the overall activity of the body
Parathormone: Hormone of the parathyroid glands; increases the level of calcium ions in the blood
Parathyroid: The endocrine glands located on the posterior sides of the thyroid gland; secrete parathormone
Parthenocarpy: The process in which ovaries develop into fruit without the fertilization in the ovules present in them; results in seedless fruits e.g. bananas
Parthenogenesis: A form of asexual reproduction in which an unfertilized egg develops into new offspring
Peripheral nervous system: A division of the nervous system that consists of nerves and ganglia
Peritoneal dialysis: The dialysis in which the dialysis fluid is pumped into the abdominal peritoneal cavity; the wastes from the blood vessels of the peritoneum diffuse into the dialysis fluid which is then drained out
Pharmaceutical drug: See medicinal drug
Pharmacology: The study of drug composition and properties and medical applications
Phenotype: The expression of the genotype in the form of trait
Phytoplankton: Photosynthetic organisms that float on the surface of water
Pituitary: The endocrine gland attached to the hypothalamus that controls many other endocrine glands in the body
Plumule: The part of the plant embryo that develops into new shoot
Pneumonia: The infection of one or both lungs; caused by specific bacteria, viruses or fungi; the infected part of the lung becomes filled with fluid and pus
Pollen tube: A tube formed by the tube nucleus of the pollen grain; carries sperms to the ovule
Pollen-sac: The part of the anther where microspore (pollen grains) are produced
Pollination: The transfer of pollen grains from flower’s anther to stigma
Pollutant: The substance that causes pollution
Pollution: Undesirable change in the physical, chemical or biological characteristics of air, water and land that may harmfully affect living organisms and other resources
Pons: Part of the hindbrain; present on top of the medulla; assists the medulla in controlling breathing and serves as a connection between the cerebellum and the spinal cord
Predation: An interaction between animals of two species or any plant and an animal, in which the predator attacks, kills and feeds on the smaller animal called prey
Pressure filtration: The first step in urine formation; the process in which most of the water, salts, glucose and urea of the blood is forced out of the glomerulus and passed into Bowman’s capsule
Producer: An organism that produces organic compounds from inorganic compounds; an autotroph
Progesterone: A hormone secreted by the ovaries that maintains the uterus during pregnancy
Prostate gland: An accessory gland in the male reproductive system; produces a secretion that neutralizes the acidity
Proximal convoluted tubule: The part of the nephron between Bowman’s capsule and the loop of Henle
Pupil: The opening in the centre of the iris of the eye
Pyramid of Biomass: The graphic representation of biomass present per unit area at different trophic levels in an ecosystem
Pyramid of Numbers: The graphic representation of the number of individuals per unit area at various trophic levels in an ecosystem
Radicle: The part of the plant embryo that develops into new root
Receptors: The organs, tissues or cells which detect particular type of stimuli
Recessive trait: The trait which is masked in the offspring of a cross between two homozygous individuals showing contrasting forms of the trait
Recombinant DNA: The vector DNA and the attached gene of interest
Reflex Action: The involuntary and immediate response to a stimulus
Reflex arc: The nerve pathway over which the nerve impulses travel in a reflex action
Renal corpuscle: The collective name for the glomerulus and Bowman’s capsule of the nephron
Renal pelvis: The funnel-shaped cavity into which the renal pyramids of kidney project
Renal pyramids: Cone-shaped areas in the renal medulla
Renal tubule: The part of the nephron after the Bowman’s capsule; consists of proximal convoluted tubule, loop of Henle and distal convoluted tubule
Renewable resources: The resources which are replenished or reproduced easily e.g. sunlight, air, wind etc.
Reproduction: The process by which organisms produce new organisms of their own kind
Restriction endonucleases: Enzymes used to cut the gene from the total DNA of the organism
Retina: The innermost and the sensitive layer in the eye
Rheumatoid arthritis: Painful inflammation of the membranes at the joints
Rhizomes: Horizontal underground stems; have scale leaves with buds; shoots of the new plant develop and grow form buds (vegetative propagation)
Rhodopsin: A pigment present in the rods of the retina
Rods: The photosensitive cells present in the retina of the eye; sensitive to dim light
Saltatory conduction: Fast nerve impulses; jump over the areas of myelin going from node to node
Schwann cells: The supporting cells around neurons; form the myelin sheath
Scrotum: A sac of skin outside the body wall in which the testes of the male are located
Sedatives: Types of drugs that interact with the central nervous system to depress its activities; make a person calm or drowsy
Seed coat: Testa: Outer covering of a seed; develops from the integument of the ovule; protects the embryo from mechanical injury and from drying out.
Seed dormancy: A period, during which there is no growth in the seed; seeds in dormancy are ripe seeds but do not germinate; under favourable conditions, the seeds break dormancy and begin to germinate
Selective re-absorption: The second step in urine formation; in it about 99% of the glomerular filtrate is reabsorbed into the blood capillaries surrounding the renal tubule
Semen: The material containing sperms in a fluid
Semicircular canals: The three bony canals present posterior to the vestibule in the inner ear
Seminal vesicle: The associated gland in male reproductive system; produces secretions having nutrients for the sperms
Seminiferous tubule: The coiled tubes present in testes; sperms are formed in these tubules
Sensory nerves: The nerves which contain only the axons of sensory neurons
Single-Cell Protein: The protein content extracted from pure or mixed cultures of algae, yeasts, fungi or bacteria; the micro-organisms are grown in fermenters where they produce a high yield of protein
Skeleton: The framework of hard, articulated structures that provide physical support, attachment for skeletal muscles, and protection for the bodies of animals
Somatic Nervous system: The part of the motor pathway of the peripheral nervous system; gives voluntary control; includes all of the motor neurons that conduct impulses from the CNS to the skeletal muscles
Somatotrophin: Growth hormone: A hormone of the anterior pituitary;promotes the growth of the body
Sperm: The male gamete
Spermatid: The immature non-motile forms of sperms; are converted into sperms after many changes
Spermatogenesis: The formation of sperms
Spermatogonia: The diploid cells in semineferous tubules of the testes; divide mitotically and produce primary spermatocytes
Spinal nerves: The nerves which arise from the spinal cord
Spongy bone: The soft and porous interior of the bone; contains blood vessels and bone marrow
Sporophyte: The diploid generation in plant life cycle; produces spores
Stamen: The part of the androcium; consists of anther and filament
Sternum: The chest bone
Stigma: The upper part of the carpel
Style: The middle portion of the carpel
Sulfonamides: Sulpha drugs: Synthetic antibiotics that contain the sulfonamide group; bacteriostatic in action
Suspensory ligament: The ring that attaches the lens of the eye to the ciliary muscles
Symbiosis: Long or short term relationship between members of different species; three forms are parasitism, commensalism and mutualism
Sympathetic nervous system: Part of the autonomic nervous system; prepares the body to deal with emergency situations
Synapse: A junction between a neuron and another cell; transmits nerve impulse from one neuron to the next neuron or to effector’s cell
Tendon: Tough connective tissue that attaches muscles to bones
Testa : See Seed coat
Testis : The male gonads ; produces sperms and male sex hormones
Testosterone: The male sex hormone secreted by testis; stimulates the development of male reproductive system and the male secondary sex characteristics
Tetracycline: Broad-spectrum bacteriostatic antibiotics; inhibit bacterial protein synthesis
Thalamus: The part of the forebrain; serves as a relay centre between various parts of the brain and spinal cord
Thyroid: The endocrine gland located in front of the trachea; secretes hormones thyroxin and calcitonin
Thyroxin: The hormone of the thyroid gland; increases the break down of food and release of energy; also responsible for the growth of body
Trachea: Windpipe: Part of the air passageway between larynx and bronchi
Trait: The characteristics which are controlled and transmitted to next generations through genes
Transgenic: Organisms with modified genome (genetic make-up)
Triceps: An extensor muscle on the back of the upper arm bone
True-breeding: The homozygous individual
Tubers: The swollen ends of slender rhizomes (underground stem); new plants develop from buds on the stem tubers (vegetative propagation)
Tubular secretion: The third step in urine formation; different ions, creatinine, urea etc. are secreted from the blood into the filtrate in the renal tubule
Tympanum: Tympanic membrane: See Ear drum
Ureter: A tube that carries urine from a kidney to the urinary bladder
Urethra: The tube that carries urine from urinary bladder to the outside of the body
Urinary system: The system responsible for the production and excretion of urine; includes kidneys, ureters, urinary bladder and urethra
Uterus horn: The two separate parts of the uterus in the female rabbit
Variation: A characteristic in an individual that differs from the typical characteristics of other individuals of the same species
Vas deferens: The tubes that carry sperms from each testis to the urethra
Vasopressin: Antidiuretic hormone; the hormones secreted by the posterior pituitary; responsible for the reabsorption of water from renal tubules of the nephron
Vector: (in Biology) The DNA (plasmid) or bacteriophage etc. that transfers the isolated gene of interest to the host cell
Vegetative propagation: A type of asexual reproduction in which the vegetative parts of the plants i.e. roots, stems or leaves produce new generation
Vestibule: Part of the inner ear; helps to maintain balance of the body
Vitreous humour: The fluid present in the posterior chamber of the eye i.e. between the iris and retina
Vocal cords: Two pairs of fibrous bands in the larynx; vibrate when the air passes through them and produce sounds.