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433 Cards in this Set
- Front
- Back
A molecule consisting of two amino acids joined by a peptide bond.
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Dipeptide
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The process of taking materials into a cell by surrounding them with plasma membrane, which pinches off to form a vesicle inside the cell. This is an active process requiring ATP.
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Endocytosis
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A specialised area adapted to make it easier for molecules to cross from one side of the surface to the other.
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Exchange surface
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Taxonomic group used in the classification of living organisms. Contains related genera.
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Family
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A vessel used to grow microorganisms in large numbers.
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Fermenter
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Sex cells, usually haploid (one set of chromosomes). Fuse during sexual reproduction to form zygotes (diploid).
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Gamete
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The sum total and variety of all the genes in a population or species at a given time.
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Gene pool
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The covalent bond formed when carbohydrate molecules are joined together in condensation reactions.
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Glycosidic bond
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The place where an organism or population lives. It includes the climatic, topographic and edaphic factors as well as the plants and animals that live there.
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Habitat
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The iron-containing prosthetic group found in haemoglobin.
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Haem
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The acid produced when haemoglobin takes up hydrogen ions.
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Haemoglobinic acid
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The rupturing of animal cell surface membranes, and subsequent release of their contents, when cells placed in a solution of higher water potential and water enters by osmosis.
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Haemolysis
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Complete mental, physical and social wellbeing.
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Health
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Type of protein associated with DNA in eukaryotes. DNA is wound around them to form chromatin.
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Histone
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Chemicals made in endocrine glands that are carried in the blood to target cells/tissues/organs. They act as chemical messengers.
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Hormone
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A chain of carbon atoms bonded together with hydrogen atoms bonded onto the carbons.
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Hydrocarbon chain
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A response to an antigen, which involves the activation of lymphocytes.
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Immune response
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Ability of the immune system to respond very quickly to antigens that it recognises as they have entered the body before.
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Immunological memory
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The number of new cases of a disease in a certain time period.
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Incidence
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The theory of enzyme action in which the enzyme molecule changes shape to fit the substrate molecule more closely as it binds to it.
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Induced fit (hypothesis)
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A group of factors with non-specific antiviral activity. They also affect the immune system.
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Interferon
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Inside the cell.
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Intracellular
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An atom (or group of atoms) carrying a positive or a negative charge.
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Ion
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Attraction between oppositely charged ions.
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Ionic bond
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Fibrous protein found in skin, hair and nails.
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Keratin
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White blood cells.
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Leucocytes
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A diverse group of chemicals that includes triglycerides, fatty acids and cholesterol.
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Lipids
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The simple theory of enzyme action where the active site is directly complementary to the substrate molecule.
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Lock-and-key hypothesis
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A cavity surrounded by a cell wall in cells, such as xylem vessels, which have lost their cell contents. Also used for the central cavities of blood vessels.
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Lumen
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A type of white blood cell activated as part of the immune response.
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Lymphocyte
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Membrane-bound vesicles made by pinching off from the Golgi body. They usually contain digestive enzymes.
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Lysosomes
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Large, phagocytic, amoeba-like white blood cells that engulf, ingest and destroy bacteria, damaged cells and worn-out red blood cells.
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Macrophages
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The number of time greater an image is than the object.
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Magnification
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A type of RNA polynucleotide involved in protein synthesis. Carries the information coding for a polypeptide from the nucleus to the ribosomes in the cytoplasm.
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Messenger RNA (mRNA)
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Proteins associated with microtubules. The proteins can move along microtubules. Kinesin moves towards the (+) end of the microtubules and dynein moves towards the (–) end.
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Microtubule motors
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Nuclear division that results in the formation of cells that are genetically identical to the parent cell.
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Mitosis
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A crop of plants of a single species bred to be very similar.
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Monoculture
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Large, phagocytic white blood cell.
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Monocyte
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A small molecule that is one of the units bonded together to form a polymer.
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Monomer
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A simple sugar molecule. The monomer of polysaccharides.
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Monosaccharide
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The proportion of people in a population who are ill with a particular disease at any one time.
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Morbidity
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The number of people who die from a disease in a certain time period.
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Mortality
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A slimy substance secreted by goblet cells in animal epithelial tissues. It is made up mostly of glycoproteins and protects and/or lubricates the surface on to which it is secreted.
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Mucus
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A change in the structure of DNA, or in the structure and number of chromosomes.
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Mutation
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The mass of filaments (hyphae) that make up the body of a fungus.
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Mycelium
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The mechanism for evolution in which the best-adapted organisms in a population can outcompete those that are less well-adapted.
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Natural selection
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The exact role of an organism in the ecosystem – its use of the living and non-living components of the ecosystem.
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Niche
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An inhibitor of an enzyme-controlled reaction that binds to the enzyme molecule in a region away from the active site.
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Non-competitive inhibitor
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The double membrane structure surrounding the nucleus in eukaryotic cells.
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Nuclear envelope
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The monomer of nucleic acids consisting of a phosphate, a sugar and an organic base.
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Nucleotide
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A large, membrane-bound organelle found in eukaryotic cells, which contains the genetic material in the form of chromosomes.
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Nucleus
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The total substances taken into an animal or plant for use in metabolism (the sum total of its diet).
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Nutrition
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Steroid hormone made in ovaries.
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Oestrogen
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An animal that eats plant and animal material.
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Omnivore
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Infection caused by an organism that infects a host with a weakened (compromised) immune system.
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Opportunistic infection
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A collection of tissues that work together to perform a specific overall function or set of functions within a multicellular organism.
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Organ
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Structure inside a cell. Each has a specific function and many are surrounded by membrane.
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Organelle
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Nitrogenous coompound in nucleic acid: adenine, thymine, uracil, cytosine, guanine are examples.
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Organic base
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The amount of oxygen in the air expressed as the pressure created by the presence of oxygen, expressed in kilopascals (kPa).
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Oxygen tension
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Describes blood carrying oxygen in the form of oxyhaemoglobin.
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Oxygenated
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Haemoglobin with oxygen molecules attached.
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Oxyhaemoglobin
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Describes a disease that is spreading worldwide or over continents.
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Pandemic
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Relatively unspecialised plant cells. They have living contents and thin, permeable cellulose cell walls. They may be able to photosynthesise, store food or support young plants.
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Parenchyma
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The proportion of total pressure provided by a particular gas as part of a mixture of gases.
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Partial pressure
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A membrane that will allow some molecules to pass through but will not allow some others to pass through.
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Partially permeable membrane
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Immunity acquired indirectly without activation of the lymphocytes, such as through the placenta, from breast milk, or by injection.
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Passive immunity
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An organism that causes disease.
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Pathogen
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A molecule consisting of a small number of amino acids bonded together by (covalent) peptide bonds.
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Peptide
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The covalent bond formed when amino acids are joined together in condensation reactions.
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Peptide bond
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Muscular contractions of muscle layers of gut to squeeze food along.
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Peristalsis
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Gives measure of acidity/alkalinity of a solution. It is the reciprocal of the logarithmic value of the hydrogen ion concentration.
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pH
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A cell that can carry out phagocytosis and ingest bacteria or small particles. Macrophages and neutrophils are phagocytes.
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Phagocyte
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A vacuole inside a phagocyte which is created by an infolding of the plasma (cell surface) membrane to engulf a foreign particle. The foreign particle is held inside this.
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Phagosome
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A tissue in plants that is used to transport dissolved sugars and other substances.
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Phloem
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A molecule consisting of a glycerol molecule, two fatty acid molecules and a phosphate group covalently bonded together. Forms the basis of cell membranes.
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Phospholipid
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Process by which plants, some bacteria and some protoctists make food using carbon dioxide, water and sunlight energy.
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Photosynthesis
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The evolutionary relationships between organisms.
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Phylogeny
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A taxonomic group used in classification of living organisms. Contains similar classes.
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Phylum
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The process of endocytosis involving the bulk movement of liquids into a cell.
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Pinocytocis
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Thin areas in the lignified walls of xylem tissue cells that allow communication between adjacent cells.
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Pits (or bordered pits)
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Fatty material built up under the endothelium of an artery.
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Plaque
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Mature B-lymphocytes (white blood cells) that secrete a specific kind of antibody.
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Plasma cells
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Proteins made in the liver that are found in the non-cellular fraction of the blood.
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Plasma proteins
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Small, circular piece of DNA present in some bacterial cells. May have genes for antibiotic resistance and can also be used as vectors in genetic engineering.
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Plasmid
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A fine strand of cytoplasm that links the protoplasm of adjacent cells through a thin area of cell wall called a pit.
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Plasmodesma(ta)
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Detachment of the plasma membrane from the cell wall as the cytoplasm shrinks when water is lost from a plant cell.
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Plasmolysis
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Fragments of cells in the blood that play a part in blood clotting.
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Platelets
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Stem cells capable of differentiating to become a limited number of cell types found in the organism (e.g. cells of an early embryo).
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Pluripotent
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A large molecule made up of many/repeating similar, smaller molecules (monomers) covalently bonded together.
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Polymer
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A polymer consisting of many nucleotide monomers covalently bonded together (DNA and RNA are examples).
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Polynucleotide
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A polymer consisting of many amino acid monomers covalently bonded together.
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Polypeptide
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A polymer consisting of many monosaccharide monomers covalently bonded together.
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Polysaccharide
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Apparatus used to measure water uptake in a leafy shoot and so to estimate rate of transpiration.
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Potometer
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A suspension of small solid particles in a liquid, produced by a chemical reaction.
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Precipitate
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The number of people with a particular disease at a certain time.
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Prevalence
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The defences that prevent the entry of a pathogen into the body.
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Primary defences
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The sequence of amino acids found in a protein molecule.
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Primary structure
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An organism with cells that do not contain a true nucleus.
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Prokaryote
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The phase of mitosis where the chromosomes become visible as a pair of sister chromatids joined at the centromere.
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Prophase
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A non-protein organic molecule that forms a permanent part of a functioning protein molecule.
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Prosthetic group
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An enzyme capable of digesting proteins.
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Protease
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A polymer consisting of many amino acid monomers covalently bonded together.
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Protein
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The circulation of the blood through the lungs.
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Pulmonary circulation
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The vein carrying oxygenated blood from the lungs to the left atrium of the heart.
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Pulmonary vein
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Adenine and guanine – nitrogenous bases consisting of a double ring structure.
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Purine
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Specialised tissue (muscle fibres) in the septum of the heart that conducts the electrical stimulus from the sinoatrial node to the ventricles.
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Purkyne tissue (Purkinje tissue)
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Thymine, cytosine and uracil – nitrogenous bases consisting of a single ring structure.
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Pyrimidine
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A square frame used for sampling in field work.
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Quadrat
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A study is that does not involve quantity (numbers). For example, simple observations to see if a particular species lives in a selected area.
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Qualitative
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A study involving quantity (numbers). For example, if you count the number of individuals of a species in a selected area.
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Quantitative
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Protein structure where a protein consists of more than one polypeptide chain e.g. Haemoglobin and insulin.
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Quaternary structure
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Protein or glycoprotein molecules on cell surfaces, used for attachment of specific substances such as hormones or viruses.
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Receptor sites
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A carbohydrate monomer or dimer that gives a positive result in Benedict’s test because it is able chemically to reduce copper sulfate in solution.
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Reducing sugar
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Chemical reaction involving the gain of electrons or the addition of hydrogen.
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Reduction
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The ability to distinguish two separate points as distinct from each other.
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Resolution
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The process in which energy is released from complex molecules, such as glucose, within cells and transferred to molecules of ATP.
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Respiration
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The 5-carbon (pentose) sugar found in RNA nucleotides.
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Ribose
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The nucleic acid found in ribosomes.
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Ribosomal RNA (rRNA)
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The organelle on which proteins are synthesised inside the cell.
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Ribosome
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A factor that increases the chance that you may develop a particular disease.
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Risk factor
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A single-stranded polynucleotide molecule that exists in three forms. Each form plays a part in the synthesis of proteins within cells.
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RNA
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Cells in the epithelium of roots that have long extensions to increase surface area for the absorption of water and minerals.
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Root hair cells
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Defences that attempt to kill or inactivate pathogens that have already invaded the body.
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Secondary defences
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The local coiling or folding parts of a protein molecule due to the formation of hydrogen bonds formed as the protein is synthesised. E.g. a-helix and b-pleated sheets.
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Secondary structure
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The release of a substance made inside the cell using the process of exocytosis.
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Secretion
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An external pressure that drives evolution in a particular direction.
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Selection pressure
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The replication of a DNA strand where the replicated double helix consists of one old strand and one newly synthesised strand.
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Semi-conservative replication
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Valves between the ventricles and the main arteries leading out of the heart, which prevent backflow of blood.
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Semilunar valves
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The wall separating the ventricles of the heart.
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Septum
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Production of a new individual formed by the fusing of gametes from two different parents so that the offspring have a unique combination of alleles from both parents.
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Sexual reproduction
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A cell in phloem tissue through which sap is transported. It has very little cytoplasm, no nucleus, and non-thickened cellulose cell walls, with the end walls perforated.
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Sieve tube element
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The movement of molecules from a region of their higher to lower concentration.
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Simple diffusion
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A circulation in which blood flows through the heart once during each circulation of the body.
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Single circulatory system
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A part of a plant that removes sugars from the phloem.
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Sink
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The patch of tissue that initiates the heartbeat by sending waves of excitation over the atria.
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Sinoatrial node (SAN)
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A type of muscle (involuntary muscle) found mostly in certain internal organs and involved in involuntary movements such as peristalsis.
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Smooth muscle
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A solid that dissolves in a liquid.
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Solute
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The component of water potential that is due to the presence of solutes – the potential energy of a solution provided by the solutes.
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Solute potential (Ys)
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Liquid with dissolved solids.
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Solution
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A liquid that dissolves solids.
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Solvent
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A part of the plant that releases sugars into the phloem.
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Source
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The formation of a new species.
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Speciation
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A group of organisms whose members are similar to each other in shape, physiology, biochemistry and behaviour, and can interbreed to produce fertile offspring.
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Species
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A structure consisting of protein fibres found in eukaryotic cells during cell division. They guide the movement of chromosomes to opposite end of the cell at telophase.
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Spindle
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A polysaccharide found in plant cells. It is formed from the covalent bonding together of many glucose molecules.
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Starch
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Undifferentiated cells that are capable of becoming differentiated to a number of possible cell types.
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Stem cells
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Pore in leaf epidermis, surrounded by two guard cells. Changes in turgidity of the guard cells can open or close the stoma. Allow gaseous exchange and transpiration in plants.
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Stoma (pl: stomata)
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The gel-like matrix found in chloroplasts. The membranes of the thylakoids/grana are embedded in it.
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Stroma
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The substance that is used up in an enzyme-controlled reaction, leading to the formation of product. It fits into the active site of the enzyme at the start of the reaction.
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Substrate
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The ‘skin’ on the surface of water formed as a result of hydrogen bonding in water molecules pulling the surface molecules downwards.
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Surface tension
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A chemical that can reduce the surface tension of a film of water.
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Surfactant
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Development that does not cause excessive harm to the surrounding environment. The local biodiversity and people can continue to live and operate alongside the development.
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Sustainable development
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Speciation that occurs within one area – some factor other than geographical separation has prevented free interbreeding between members of the species.
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Sympatric
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The route taken by water through the cytoplasm of cells in a plant.
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Symplast pathway
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The circulation that carries blood around the body, excluding the circulation to the lungs.
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Systemic circulation
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The stage of the heart cycle in which heart muscle contracts to pump blood.
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Systole
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A taxonomic group, such as a class or a family, used to aid classification.
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Taxon (pl: taxa)
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The study of the principles behind classification.
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Taxonomy
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Final phase of mitosis. Two new nuclear envelopes form around the two new nuclei.
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Telophase
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String-like tendons used to attach the atrioventricular valves of the heart to the sides of the ventricle wall. Sometimes called heart strings.
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Tendinous cords
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The overall three-dimensional shape of a protein molecule. Involves hydrogen bonding, disulfide bridges, ionic bonds and hydrophobic interactions.
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Tertiary structure
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Steroid hormone made in the testes.
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Testosterone
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A blood clot.
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Thrombus
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Flattened membrane sacs in chloroplasts, which hold the pigments used in photosynthesis and are the site of the light reactions. A stack of thylakoids forms a granum.
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Thylakoid
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A nitrogen-containing organic base found in DNA. It pairs with adenine.
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Thymine
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A group of similar cells that perform a particular function.
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Tissue
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The fluid, derived from blood plasma, that surrounds the cells in a tissue.
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Tissue fluid
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Undifferentiated cell that is capable of differentiating into any kind of specialised cell.
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Totipotent
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The windpipe leading from the back of the mouth to the bronchi.
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Trachea
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The assembly of an mRNA molecule that is a copy of the DNA coding strand (and complementary to the template strand).
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Transcription
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A line through a habitat used to help take samples and study the habitat.
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Transect
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A type of polynucleotide involved in protein synthesis. It transports amino acids to the ribosomes to be added to the growing polypeptide chain.
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Transfer RNA (tRNA)
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Organism that has genetic material from another organism, usually by genetic engineering.
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Transgenic
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The movement of sucrose and other substances up and down a plant.
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Translocation
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The way in which a microorganism or other pathogen travels from one host to another.
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Transmission
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The loss of water vapour from the aerial parts of a plant due to evaporation.
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Transpiration
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A molecule consisting of a glycerol molecule and three fatty acid molecules covalently bonded together.
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Triglyceride
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Describes a cell that is full of water as a result of entry of water due to osmosis such that pressure of the cell wall prevents more water entering.
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Turgid
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The detailed structure of the internal components of cells as revealed by the electron microscope rather than by the light microscope.
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Ultrastructure
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A nitrogen-containing organic base found in RNA. Pairs with adenine.
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Uracil
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Chemical made in the liver from amine groups from deaminated amino acids and carbon dioxide. It is toxic and is removed from the body in urine.
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Urea
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A preparation of antigens given to provide artificial immunity.
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Vaccine
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The pathway taken by water in plants as it passes from cell to cell via the cell cytoplasm and vacuole.
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Vacuolar pathway
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Condition in an experimental investigation. Can be independent (altered by the experimenter) or dependent (respond to changes in the independent variable).
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Variable
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The differences between individuals.
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Variation
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The transport tissue in a plant – usually found as a bundle containing both xylem and phloem.
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Vascular tissue / bundle
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An organism that carries a disease-causing organism (pathogen) from one host to another. Also describes an agent (such as a plasmid) that can transfer genetic material.
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Vector
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Either of two large veins that carry deoxygenated blood from the body back to the heart.
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Vena cava
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Breathing – movement of diaphragm and rib cage that bring air into and out of the lungs.
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Ventilation
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The lower chambers in the heart.
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Ventricles
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A membrane-bound sac found in cells and used to transport materials around the cell.
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Vesicle
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Folds in the wall of an organ or tissue that increase surface area.
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Villi
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Chemical needed in small amounts for healthy metabolism. Some organisms can make them, some organisms have to obtain them in the diet.
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Vitamin
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A measure of the ability of water molecules to move freely in solution. Decreased by the presence of solutes.
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Water potential (Y)
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The potential energy of water vapour in a gas – it is used to indicate how much water vapour is present.
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Water vapour potential
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A plant specially adapted to living in dry areas.
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Xerophyte
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A plant tissue containing vessels (and other cells) that are used to transport water in a plant and provide support.
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Xylem
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Diploid cell made from fusion of male and female gametes.
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Zygote
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The frequency of occurrence of plants in a sampled area, such as a quadrat.
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Abundance
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The level of energy required to enable a reaction to take place. Enzymes reduce the amount of energy required to allow a reaction to proceed.
|
Activation energy
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Immunity that is acquired by activation of immune system.
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Active immunity
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The area on an enzyme molecule to which the substrate binds.
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Active site
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Force of attraction between molecules of two different substances.
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Adhesion
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A protein secondary structure – a right-handed spiral held in place by hydrogen bonds between adjacent C=O and NH groups.
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a-helix
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Speciation due to organisms of a species being separated by geographical barriers so that eventually they become so different that they cannot interbreed.
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Allopatric
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An organic compound that contains both an amino group(–NH2) and a carboxyl group (–COOH). The monomers of protein molecules.
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Amino acid
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An enzyme that catalyses the hydrolysis of starch to maltose.
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Amylase
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Movement of substances across membranes against their concentration gradient, requiring the use of energy in the form of ATP.
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Active transport
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A version of a gene.
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Allele
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A macrophage that has ingested a pathogen and displays some of the pathogen’s molecules on its cell surface membrane.
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Antigen-presenting cell
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The route taken by water between the cells or through the cell walls in a plant.
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Apoplast pathway
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Part of a starch molecule, consisting of many thousands of glucose residues bonded together.
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Amylose
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|
Term usually applied to the process of incorporating simple molecules of food produced by digestion into the living cells of an animal for use in metabolism.
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Assimilation
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The use of comparative studies or samples to determine the concentration or quantity of a substance in a sample.
|
Assay
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A nitrogen-containing organic base found in nucleic acids. It pairs with thymine in DNA and with uracil in RNA.
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Adenine
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An organism that makes its own food from simple inorganic molecules, such as carbon dioxide and water.
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Autotroph
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Protein molecules released by the immune system in response to an antigen, which are capable of neutralising the effects of the antigen.
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Antibodies
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The production of genetically identical new organisms by a single ‘parent’ organism.
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Asexual reproduction
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Rules governing the complementary bases in nucleic acids. Adenine pairs with thymine (or uracil). Guanine pairs with cytosine.
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Base-pairing rules
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Describes tissue consisting of cells that store fat/lipid.
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Adipose
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One of the upper chambers in the heart.
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Atrium
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A molecule used to store energy temporarily in organisms. The molecule is broken down to adenosine diphosphate + phosphate to release energy to drive metabolic processes.
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ATP
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Hardening of the artery walls and loss of elasticity caused by atherosclerosis or by deposition of calcium.
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Arteriosclerosis
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A biochemical test for the presence of proteins.
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Biuret test
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Airways in the lungs that lead from the trachea to the bronchioles.
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Bronchi
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Immunity acquired as a result of deliberate exposure to antigens or by the injection of antibodies.
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Artificial immunity
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The process of deposition of fatty substances in the lining of arteries to form atheroma, which may eventually lead to arteriosclerosis (hardening of the arteries).
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Atherosclerosis / atheroma
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|
The muscle found in the heart. It has its own intrinsic heartbeat (it is myogenic).
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Cardiac muscle
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|
A protein found in membranes, which is capable of carrying a specific molecule or ion through the membrane by active transport.
|
Carrier protein
|
|
To use known concentrations of a substance in a solution to make a standard curve on a graph. This can be used to determine the amount of that substance in solutions of unknown concentration.
|
Calibration
|
|
The region of a chromosome where two sister chromatids are joined together, and where the spindle fibre attaches during cell division.
|
Centromere
|
|
A carbohydrate polymer (of b-glucose) that forms plant cell walls.
|
Cellulose
|
|
A patch of tissue in the septum of the heart that conducts the electrical stimulus from the atria in the heart through to the Purkyne fibres.
|
Atrioventricular node (AVN)
|
|
A flexible ring of cartilage that holds the airways open.
|
Cartilage ring
|
|
Material staining dark red in the nucleus during interphase. It consists of nucleic acids and proteins. Condenses into chromosomes during prophase of nucler division.
|
Chromatin
|
|
Test for reducing sugars. Sample is heated to 80ºC with reagent. If a reducing sugar is present, the reagent changes from blue to red precipitate.
|
Benedict’s test
|
|
The sequence of events making up one heartbeat.
|
Cardiac cycle
|
|
Describes a result/data point that does not appear to fit the pattern of the other results.
|
Anomalous
|
|
Genetically identical cells or individuals.
|
Clones
|
|
The movement of chloride ions into red blood cells to balance the loss of hydrogencarbonate ions.
|
Chloride shift
|
|
Feature of a living organism that increases its chances of survival, for example thick fur on an animal that lives in a cold habitat.
|
Adaptation
|
|
An organelle from which the spindle fibres develop during cell division in animal cells.
|
Centriole
|
|
A foreign molecule (which may be protein or glycoprotein) that can provoke an immune response.
|
Antigen
|
|
Also called selective breeding – the process of improving a variety of crop plant or domesticated animal by breeding from individuals with desired characteristics.
|
Artificial selection
|
|
The attraction between water molecules due to hydrogen bonding.
|
Cohesion
|
|
Plant tissue in the stem and root that contains dividing cells.
|
Cambium
|
|
In mitosis, the stage when the newly separated chromatids are pulled towards opposite poles of the nuclear spindle.
|
Anaphase
|
|
An animal that eats meat.
|
Carnivore
|
|
Also known as the Plasma membrane.
|
Cell surface membrane
|
|
A flexible, slightly elastic connective tissue.
|
Cartilage
|
|
Hormone-like proteins produced by vertebrates, which are used for communication between cells, allowing some cells to regulate the activities of others.
|
Cytokines
|
|
The network of protein fibres and microtubules found within the cell that gives structure to the cell and is responsible for the movement of many materials within it.
|
Cytoskeleton
|
|
A lipid molecule (not a triglyceride) found in all cell membranes and involved in the synthesis of steroid hormones.
|
Cholesterol
|
|
A strip of waterproof material (suberin) in the cell walls of root endodermis cells. It blocks the apoplast pathway.
|
Casparian strip
|
|
Airways in the lungs that lead from the bronchi to the alveoli.
|
Bronchioles
|
|
A chemical system that resists changes in pH by maintaining a constant level of hydrogen ions in solution. Certain chemicals dissolved in the solution are responsible for this.
|
Buffer
|
|
To make narrow. For example, in the narrowing of blood vessels.
|
Constrict
|
|
The division of selected cells by mitosis to increase their numbers.
|
Clonal expansion
|
|
The selection of cells (of the immune system) with a specific receptor site. These cells will undergo expansion as part of the immune response.
|
Clonal selection
|
|
The division of the cell, following nuclear division, to form two new cells.
|
Cytokinesis
|
|
A linear DNA molecule wrapped around histone proteins found in the nucleus. Become visible in prophase of cell division.
|
Chromosome
|
|
State of animal cells when they have been immersed in a solution of lower water potential and have lost water by osmosis and become shrivelled.
|
Crenation
|
|
A substance that increases the rate of a reaction but does not take part in the reaction, and so is re-usable.
|
Catalyst
|
|
A substance that causes cancer.
|
Carcinogen
|
|
The folds found in the inner membrane of a mitochondrion. Stalked particles containing ATP synthase are found here.
|
Cristae
|
|
A system of naming living things using two Latin words – the genus name and the specific name.
|
Binomial system
|
|
Variation where there is a range of intermediates, such as height, hair colour and intelligence in humans. Affected by multiple genes and environment
|
Continuous variation
|
|
Trace (graph) showing the electrical activity of the heart muscle (atria and ventricles) during a cycle.
|
Electrocardiogram
|
|
Lining cells that have cilia on their cell surface.
|
Ciliated epithelium
|
|
Classification level introduced by Carl Woese dividing the kingdom Prokaryotae into two and placing all Eukaryotes into a third.
|
Domain
|
|
A type of tissue that consists of separate cells held together by a ground substance (matrix).
|
Connective tissue
|
|
A molecule or ion that helps an enzyme to work. It may be an inorganic ion or an enzyme.
|
Cofactor
|
|
A protein molecule that acts as a biological catalyst.
|
Enzyme
|
|
Variation between living organisms within a species, where there are discrete categories and no intermediates, e.g. blood groups A, B, AB or O in humans.
|
Discontinuous variation
|
|
A departure from full health.
|
Disease
|
|
A chemical bond formed by the sharing of one or more electrons between two atoms.
|
Covalent bond
|
|
The effect of carbon dioxide concentration on the affinity of haemoglobin for oxygen.
|
Bohr shift / Bohr effect
|
|
A molecule consisting of two monosaccharide sugars joined by a glycosidic bond.
|
Disaccharide
|
|
Describes a disease that is always present in an area. May also mean a species that is found only in a particular area and nowhere else.
|
Endemic
|
|
A measure of how far apart two organisms are on the evolutionary scale.
|
Evolutionary distance
|
|
An attractive force between substances or particles.
|
Affinity
|
|
Molecules produced by microorganisms that kill or limit the growth of other microorganisms
|
Antibiotics
|
|
Valves between the atria and ventricles that prevent backflow of blood.
|
Atrioventricular valves
|
|
Method of cell division in bacteria. The DNA replicates and the cell divides into two, each having the same DNA as the parent cell.
|
Binary fission
|
|
The number and variety of living things to be found in the world, in an ecosystem or in a habitat.
|
Biodiversity
|
|
A class of biological molecules with the general formula Cx(H2O)y. It includes sugars, starches, glycogen and cellulose.
|
Carbohydrate
|
|
Small air sacs in the lungs.
|
Alveoli
|
|
Pigments found in chloroplasts of plant (and some protoctist) cells. Each molecule consists of a hydrocarbon tail and a porphyrin ring head with a magnesium atom.
|
Chlorophyll
|
|
A replicated chromosome appears as two strands in early stages of cell division. Each strand is called a…..
|
Chromatid
|
|
Short extensions of eukaryotic cells, typically 2–10 µm long and 0.03 µm in diameter. Used for locomotion or to move fluids or mucus over a surface.
|
Cilia
|
|
Numerical value found by dividing an individual’s mass in kg by the (height in m)2 and used to assess if the individual is underweight, acceptable weight, overweight or obese.
|
Body mass index
|
|
The movement of cells or organisms towards or away from a particular chemical.
|
Chemotaxis
|
|
Refers to structures that fit together because their shapes and/or charges match up. For example, adenine and cytosine in DNA.
|
Complementary
|
|
The difference in concentration of a substance between two regions.
|
Concentration gradient
|
|
Taxonomic group used in classification of living organisms. Below phyla but containing orders (consisting of families, genera and species).
|
Class
|
|
Tissue in plant roots and stems between epidermis and vascular tissue.
|
Cortex
|
|
Vessels that carry blood to the heart muscle.
|
Coronary arteries
|
|
The molecule resulting from combination of carbon dioxide and haemoglobin.
|
Carbaminohaemoglobin
|
|
The 5-carbon sugar in DNA nucleotides.
|
Deoxyribose
|
|
A cell in the phloem involved in actively loading sucrose into the sieve tube elements, to which it is linked by many plasmodesmata.
|
Companion cell
|
|
Part of an experimental investigation – set up to show that the variable being investigated is responsible for the change observed.
|
Control
|
|
A sheet of muscular and fibrous tissue separating the chest cavity from the abdominal cavity.
|
Diaphragm
|
|
Processes that lead to communication and coordination between cells. Hormones binding to their receptors on the cell surface membrane are an example.
|
Cell signalling
|
|
Blood with haemoglobin that carries no or little oxygen.
|
Deoxygenated
|
|
A nitrogen-containing organic base found in nucleic acids. It pairs with guanine in DNA.
|
Cytosine
|
|
A type of chemical reaction in which two molecules are joined together by means of a covalent bond to form a larger molecule, and at the same time a water molecule is released.
|
Condensation
|
|
To make wider. For example, when the lumens of blood vessels become wider.
|
Dilate
|
|
The separation of a molecule into two molecules, atoms or ions without breakage of a covalent bond. For example, the release of oxygen from oxyhaemoglobin.
|
Dissociation
|
|
Conservation in areas other than the natural habitat.
|
Conservation ex situ
|
|
A protein in a cell membrane that allows movement of one molecule when linked to the movement of another molecule in the same direction by active transport.
|
Cotransporter
|
|
A suspension of one material in another as droplets, because it does not dissolve. For example, fat droplets dispersed in water.
|
Emulsion
|
|
A ring of cells between the cortex of a root and the area housing the xylem and phloem.
|
Endodermis
|
|
A polymer of nucleotide molecules that form the instructions for the synthesis of proteins found within organisms. These nucleotides contain the 5-carbon sugar deoxyribose.
|
DNA
|
|
The study of patterns of disease and the factors that influence their spread.
|
Epidemiology
|
|
The intermediate structure formed when a substrate molecule binds to an enzyme molecule.
|
Enzyme–substrate complex
|
|
Removal of amine (NH2) group from an amino acid
|
Deamination
|
|
A tissue that lines the inside of a structure, such as a blood vessel.
|
Endothelium
|
|
Process by which the present diversity of living organisms arose from simple primitive organisms, with new species arising by natural selection.
|
Evolution
|
|
The period when the heart muscle in the ventricles is relaxing and blood pressure is at its lowest.
|
Diastole
|
|
Tissue containing the protein elastin, which is able to stretch and recoil.
|
Elastic tissue
|
|
An organic non-protein molecule that binds temporarily with substrate to an enzyme active site. It is essential for enzyme activity.
|
Coenzyme
|
|
To determine the value of intervals of a scale on an instrument, such as a thermometer.
|
Calibration
|
|
An organelle found in plants, which contains chlorophyll and is responsible for photosynthetic activity in the plant.
|
Chloroplast
|
|
The organisation of living organisms (or other items) into groups according to their shared similarities.
|
Classification
|
|
A structural fibrous protein found in connective tissue, bones, skin and cartilage. It accounts for 30% of body protein.
|
Collagen
|
|
A substance that reduces the rate of an enzyme-controlled reaction by binding to the enzyme’s active site.
|
Competitive inhibitor
|
|
The net movement of molecules or ions in a gas or liquid from an area of high concentration to an area where they are less concentrated.
|
Diffusion
|
|
A protein pore that spans a membrane, through which very small ions and water soluble molecules may pass.
|
Channel protein
|
|
The curve on a graph showing the proportion of haemoglobin that is saturated with oxygen at different oxygen tensions.
|
Dissociation curve
|
|
Any system where different parts perform specialised functions, each contributing to the functioning of the whole.
|
Division of labour
|
|
A transport system in which blood travels twice through the heart for each complete circulation of the body.
|
Double circulatory system
|
|
Conservation in the natural habitat.
|
Conservation in situ
|
|
Cells or organisms that have two copies of each chromosome in their nuclei.
|
Diploid
|
|
The regulation of metabolic pathways where the last product in a sequence of enzyme-controlled reactions becomes an inhibitor of one of the enzymes earlier in the sequence.
|
End-product inhibition
|
|
An assessment of the damage that may be caused to the (local) environment by a proposed development.
|
Environmental impact assessment
|
|
Describes the structure of DNA, a twisted helix of two strands with bases joining the strands.
|
Double helix
|
|
The bond formed when fatty acid molecules are joined to glycerol molecules in condensation reactions.
|
Ester bond
|
|
Red blood cells.
|
Erythrocytes
|
|
The development and changes seen in cells as they mature to form specialised cells.
|
Differentiation
|
|
The death of the last individual in a species.
|
Extinction
|
|
A series of membrane-bound, flattened sacs extending from the outer nuclear membrane through the cytoplasm. Comes in rough and smooth forms.
|
Endoplasmic reticulum (ER)
|
|
A tissue that covers the outside of a structure.
|
Epithelium
|
|
Outside the cell - for example describes enzymes that work outside the cell.
|
Extracellular
|
|
The difference in molecular concentration that allows diffusion to occur.
|
Diffusion gradient
|
|
The process of removing materials from the cell by fusing vesicles containing the material with the plasma membrane .
|
Exocytosis
|
|
An organism having cells with a nucleus and membrane-bound organelles.
|
Eukaryote
|
|
The intermediate structure in which product molecules are bound to an enzyme molecule.
|
Enzyme–product complex
|
|
A substance added to soil to enhance the growth of plants.
|
Fertiliser
|
|
A term used to describe plant tissue where the cells have lost turgor and are not firm.
|
Flaccid
|
|
Describes a disease that spreads to many people quickly and affects a large proportion of the population.
|
Epidemic
|
|
A biochemical test for the presence of lipids.
|
Ethanol emulsion test
|
|
Taxonomical group used in the classification of living organisms. Contains similar species.
|
Genus
|
|
A 6-carbon monosaccharide sugar. Very important source of energy within cells. Substrate for glycolysis.
|
Glucose
|
|
The movement of gases by diffusion across a barrier such as the atreous wall.
|
Gaseous exchange
|
|
In pairs, these form the stomatal pore in the epidermis plants. They control the opening and closing of the pore by changes in their turgidity.
|
Guard cells
|
|
Membrane-bound organelle in eukaryote cells. Involved in the modification and transport of proteins.
|
Golgi body
|
|
Cells that have a nucleus inside a nuclear envelope, and other membrane-bound organelles.
|
Eukaryotic cell
|
|
A polysaccharide found in animal cells. Formed from the bonding together of many glucose molecules, used as a store of glucose.
|
Glycogen
|
|
An animal that eats plant material.
|
Herbivore
|
|
The passive movement of molecules across membranes down their concentration gradient. Aided by transport proteins but no metabolic energy is required.
|
Facilitated diffusion
|
|
All the genetic material inside an organism (or cell).
|
Genome
|
|
Long fibres of the protein elastin that have the ability to stretch and recoil.
|
Elastic fibres
|
|
Associating with water molecules easily (water-loving).
|
Hydrophilic
|
|
The protein that carries oxygen in the red blood cells.
|
Haemoglobin
|
|
An irreversible change in the tertiary structure of a protein molecule. It leads to loss of function in most proteins.
|
Denaturation
|
|
A nitrogen-containing organic base found in nucleic acids. It pairs with cytosine.
|
Guanine
|
|
An animal that produces heat within its cells, from respiration, to maintain a constant body temperature.
|
Endotherm
|
|
Outer layer(s) of cells of a multicellular organism.
|
Epidermis
|
|
The strands that make up the body of a fungus.
|
Hyphae
|
|
Protein channels found in cell membranes, which can be opened or closed in response to cell signals.
|
Gated channels
|
|
All the living organisms and all the non-living components in a specific area, and their interactions.
|
Ecosystem
|
|
Proteins with relatively spherical molecules, soluble in water, often having metabolic roles in organisms.
|
Globular proteins
|
|
Mucus-secreting cells in epithelial tissue.
|
Goblet cells
|
|
A 3-carbon (alcohol) molecule. It forms the basis of lipids when fatty acids are bonded to it.
|
Glycerol
|
|
The ionised form of the product of anaerobic respiration in mammals and some bacteria.
|
Lactate
|
|
A waterproofing substance that impregnates the walls of xylem tissue. Lignin gives wood its strength.
|
Lignin
|
|
A cell or organism that has one set of chromosomes/one copy of each chromosome.
|
Haploid
|
|
A lipid with carbohydrate molecules attached.
|
Glycolipid
|
|
The model of cell membrane structure proposed by Singer and Nicholson – a phospholipid bilayer with proteins ‘floating’ in it.
|
Fluid mosaic (model)
|
|
Simple procedures that show the presence of various biological molecules in samples or structures.
|
Food tests
|
|
Cell-signalling chemicals. Some are involved in activating cells of the immune system. A type of cytokine.
|
Interleukin
|
|
A weak bond formed between partially charged atoms. It is seen in water molecules, and is important in the secondary and tertiary structure of proteins.
|
Hydrogen bond
|
|
A reaction in which a molecule is broken down into two smaller molecules by the addition of a water molecule and the breaking of a covalent bond.
|
Hydrolysis
|
|
A blind-ending branch of the lymph system found in each villus of the small intestine.
|
Lacteal
|
|
Organism that gains nutrients from complex organic molecules. These molecules are digested by enzymes to simple soluble molecules.
|
Heterotroph
|
|
Energy of movement.
|
Kinetic energy
|
|
A protein with carbohydrate molecules attached.
|
Glycoprotein
|
|
The loss of genetic variation due to (artificial) selection.
|
Genetic erosion
|
|
Taxonomic group. Living organisms are grouped into one of five: Prokaryotae, Protoctista, Fungi, Plantae and Animalia.
|
Kingdom
|
|
Mixture of lipids, mainly triglycerides with saturated fatty acids, that is solid at body temperature. Act as an energy store, insulation, waterproofing and may give buoyancy.
|
Fat
|
|
The phase of the cell cycle where synthesis of new DNA and organelles takes place.
|
Interphase
|
|
Chemical produced by monocytes to signal to other cells. Also called lymphokines.
|
Monokines
|
|
Chromosomes in diploid organisms that have the same genes at the same loci and that pair up during meiosis. Can also refer to structures that have a common evolutionary origin.
|
Homologous
|
|
Components of the cell cytoskeleton. Involved in mitosis, cytokinesis and movement of vesicles within cells.
|
Microtubules
|
|
Rate of reaction at the beginning before a significant amount of product has been formed or reactant used up.
|
Initial reaction rate
|
|
Pressure created by a fluid pushing against the sides of a container.
|
Hydrostatic pressure
|
|
Describes muscle tissue (heart muscle) that generates its own contractions.
|
Myogenic
|
|
Nuclear division that results in the formation of cells containing half the number of chromosomes of the adult cell.
|
Meiosis
|
|
B and T cells that remain in the body after an immune response. Their presence enables a much faster and greater second immune response.
|
Memory cells
|
|
Cells that make keratin.
|
Keratinocytes
|
|
A protein with a relatively long, thin structure, which is insoluble in water and metabolically inactive, often having a structural role within the organism.
|
Fibrous protein
|
|
Used by animal and plant breeders to help select individuals with the desired genotype. The desired gene is linked to a section of DNA that is easy to identify in a young individual.
|
Marker-assisted selection
|
|
A group of organisms that share a common ancestor and therefore belong to the same classification group.
|
Monophyletic
|
|
Another word for totipotent.
|
Omnipotent
|
|
A polymer of nucleotide molecules.
|
Nucleic acid
|
|
Term used to describe a large range of species in an area or a population of organisms that have significant genetic variation.
|
Diversity
|
|
All the chemical reactions that take place in an organism.
|
Metabolism
|
|
The movement of water molecules from a region of higher water potential to a region of lower water potential across a partially permeable membrane.
|
Osmosis
|
|
A system of lymph nodes and lacteals with lymph fluid.
|
Lymphatic system
|
|
A respiratory pigment (protein) with a higher affinity for oxygen than haemoglobin.
|
Myoglobin
|
|
The phase of mitosis where the chromosomes line up at the equator of the spindle.
|
Metaphase
|
|
Folds in the membrane of a cell that increase its surface area.
|
Microvilli
|
|
A disaccharide molecule consisting of two a-glucose molecules bonded together.
|
Maltose
|
|
A variable that limits the rate of a process. If it is increased, then the rate of the process will increase.
|
Limiting factor
|
|
A very large molecule.
|
Macromolecule
|
|
Muscles between the ribs, responsible for moving the rib cage during breathing.
|
Intercostal muscles
|
|
A state in which the chambers in the heart contract out of rhythm.
|
Fibrillation
|
|
The slowing of an enzyme-controlled reaction by a molecule that slows down or prevents the formation of enzyme–substrate complexes.
|
Inhibition/inhibitor
|
|
The membrane that surrounds every cell, forming the selectively permeable boundary between the cell and its environment.
|
Plasma membrane or cell surface membrane
|
|
A length of DNA that carries the code for the synthesis of one (or more) specific polypeptide(s).
|
Gene
|
|
The organelle found in cells in which most of the ATP synthesis occurs. It is the site of aerobic respiration.
|
Mitochondrion
|
|
Undifferentiated plant cells capable of rapid cell division.
|
Meristem cells
|
|
Immunity acquired through exposure to disease during the normal course of life.
|
Natural immunity
|
|
Water-repelling (water-hating).
|
Hydrophobic
|
|
Phagocytic white blood cells. They engulf and digest bacteria. They have a many-lobed nucleus, and a granular cytoplasm due to the large numbers of lysosomes present.
|
Neutrophils
|
|
An enzyme that catalyses the breakdown of lipid molecules.
|
Lipase
|
|
An organism that lives in or on another living organism (its host), deriving nutrition from the host, benefiting at the expense of its host.
|
Parasite
|
|
Taxonomic group used in classification of living organisms. Contains similar families.
|
Order
|
|
The second, longer part of the small intestine.
|
Ileum
|
|
A chemical made in the body that is involved in inflammatory reactions.
|
Prostaglandin
|
|
A layer of cells in the root that lies just inside the endodermis. It usually consists of meristematic cells whose division gives rise to lateral roots.
|
Pericycle
|
|
The condition that gives the fastest rate of reaction in enzyme-controlled reactions.
|
Optimum (temperature / pH)
|
|
Describes cytoplasm that is not divided into cells but contains many nuclei.
|
Multinucleate
|