Glossary Flashcards
Abiotic
An ecological factor that is part of the non-living and physical environment of an organism.
Action potential
The depolarisation which takes her place across the cell surface membrane of a nerve cell during the passage of an impulse.
Acetyl co-enzyme A
An intermediate product formed during respiration during the link reaction.
Acetylcholine
A neurotransmitter involved in the transmission of impulses across synapses and released into the synaptic cleft when an impulse arrives at the membrane
Acrosome
An organelle in the head of a sperm that contains digestive enzymes which digests the follicle cells and jelly like layer of the egg, allowing the sperm to fertilise the egg
Action potential
The change in potential difference between inside and outside a nerve cell which takes place across the cell surface membrane during the the passage of an electrical impulse
Active artificial immunity
Immunity that develops following immunisation with antigens in a vaccine
Active transport
The movement of substances from an area of low concentration to an area of higher concentration against a concentration gradient, requiring ATP
Adhesion
A force resulting from attraction between molecules of different substances
Aerobic capacity
The ability to take in, transport and use oxygen - which determines our ability to undertake long periods of vigorous exercise
Agonist
A substance which mimics the action of a neurotransmitter at a synapse and fits into the receptor molecules for specific neurotransmitter e.g. Dopamine agonists used for Parkinson’s
Aneurysm
A weakening of the wall of an artery due to high blood pressure, which results in a balloon like swelling
APC
A phagocyte which carries antigens on its surface in order to trigger the specific immune system
Arthroscopy
Keyhole surgery on joints, during which a very small incision is made and a fibre optic tube and small surgical instrument are used to repair damage
Basal ganglia
A group of neurones within each cerebral hemisphere of the brain responsible for selecting and initiating stored programmes for movement
Biodiversity
The variety of living organisms in an habitat - both on a species level and a genetic levels (diversity of alleles present in a population)
Bipolar neurone
A type of nerve cell in the retina which has a cell body with a dendron and an axon
Blood clotting
The action of fibrinogen being converted to fibrin, which forms a mesh of protein fibres over the surface of a wound or a damaged artery
BMI
Body mass/height^2
Carbon fixation
The process which converts CO2 into carbon compounds such as GP, normally occurring during the Calvin cycle and catalysed by Rubisco
Cardiac output
The total volume of blood pumped out of the left verticale of the heart in one minute (stroke volume x bpm)
Carrier protein
A protein which binds with a specific ion or molecule and helps it cross a membrane
CD4 receptor
A receptor molecule found in the cell surface membrane of T helper cells which is complementary in shoe to the antigen fragment displayed by an APC
Centromere
The region on a chromosome where to chromatids are held together during mitosis and the spindle fibres attach
Cerebellum
Part of the hindbrain which is responsible for posture, balance and coordination
CFTR protein
A channel protein that allows sodium to leave a cell, and whose malfunctioning causes Cystic Fibrosis
Chiasma
Places where chromosomes can be seen to cross over each other during meiosis and the daughter chromatids break and rejoin, rearranging genetic material
CVS
Genetic screening procedure in which placental tissue is removed 8-12 weeks into pregnancy and is tested
Clonal selection
The division of a particular B into b Effector and b memory cells in the specific immune response as a result of an antigen binding to the B cell with a complementary receptor
Bacterial conjugation
A process which occurs in bacteria in which DNA is passed from one cell to another
Critical period
A period of time during development when the nervous system must obtain specific experiences in order for the correct patterns of synapses within the brain to be created
Dark adaptation
The re-formation of rhodopsin when one enters a dark room
Dendrochronology
The determination of the age of a piece of wood through the counting of its tree rings
Dihybrid inheritance
A genetic cross involving genes at two different loci which are not linked
Semi- conservative DNA replication
The process in which a molecule of DNA produces two exact copies of itself before mitosis by creating a new DNA molecule consisting of one of the existing chains of DNA and one completely new one
Erthyropoietin
A hormone, produced by the kidney, which increases the rate of production of red blood cells and can be taken as a performance-enhancing drug
Fick’s law
Surface area x difference in concentration / thickness of gas exchange surface
fMRI
Brain scanning which depends on using radio waves to determine oxygen uptake in particular areas of the brain by distinguishing between haemoglobin and oxyhaemoglobin
Ganglion neurone
Neurones which synapse with bipolar neurones in the eye and that have axons which make up the optic nerve
GPP
NPP x Respiration
Goblet cell
A mucus producing cell
Histones
Proteins which help package DNA, which is tightly wound around them
IAA
The most commonly occurring plant hormone of the class auxins
Induced fit theory
Model to explain the way which an enzyme enables a substrate to participate in a chemical reaction which hypothesises that when the substrate enters the active site, the enzyme changes shape to fit more closely around the substrate
Intergrase
An enzyme that inserts virus DNA into the host cell DNA
Interferon
A substance produced by the cells of a mammal when they are attacked by a virus by inhibiting the synthesis of viral proteins
Linkage analysis
A technique that follows the inheritance of DNA markers and is used to find the loci of certain alleles responsible for diseases by knowledge of the position in relation to a gene which is linked to it
