Edexcel A level Biology
Acrosome reaction - ANS- Enzymes released by the acrosome digest the zona pellucida.
Action potential - ANS- The change in voltage from +40 to -70mV that occurs during
repolarisation.
Allopatric - ANS- Due to geographical isolation
Amniocentesis - ANS- A large needle is used to extract amniotic fluid, which
Antagonistic muscles - ANS- Muscle pairs arranged to work against each other to move
a joint.
Antibody - ANS-
Antigen presenting cells - ANS- Cells which display the antigens of the foreign cells on
their surface for other cells to recognise.
Apoptosis - ANS- Programmed cell death.
Auxins - ANS- Plant hormones that stimulate growth by causing cells to elongate.
Axon - ANS- This conducts an impulse away from the cell body.
B helper cells - ANS-
Basal Ganglia - ANS- A collection of neurones deep in each hemisphere which select
and initiate stored programs for movement.
Biodiversity - ANS- The diversity of plant and animal life in a particular habitat
Candidate Gene - ANS- A gene that is likely to cause a disease.
Carpentered world hypothesis - ANS- People who live in a world with many straight lines
and right angles tend to interpret obtuse and acute angles as right angles.
Cerebellum - ANS- This is responsible for balance and co-ordinating movement by
receiving information from the motor cortex, muscles and joints.
Chorionic villus sampling - ANS-
, Cones - ANS- Cones are cells in the retina which detect colour.
Corpus callosum - ANS- White matter made up mainly of axons. It provides connections
between the cortex and other brian structures. It also forms connections between the two
hemispheres of the brain.
Cortex - ANS- This is the grey folded matter around the brain.
Cortical reaction - ANS- Release of enzymes by the cortical granules which cause the
zona pellucida to thicken.
Dendrites - ANS- These conduct impulses towards the cell body.
Depolarisation - ANS- When the polarisation across the cell membrane is reversed,
making the inside of the axon positive and the outside negative.
DNA - ANS- Deoxyribose nucleic acid. Carries the genetic information for cells and some
viruses.
Drug targets - ANS- Molecules which can be altered by the binding of a drug.
Ecosystem - ANS- Organisms and their interactions with biotic and abiotic factors.
Excitatory synapse - ANS- These synapses make the postsynaptic membranes more
permeable to sodium ions.
Frontal lobe - ANS- This is concerned wth high reasoning, personality, forming
associations and ideas. It includes the primary motor cortex which stores information on
how to carry out movements.
Habitat - ANS- The natural environment in which a species lives.
Hippocampus - ANS- Where long term memory is stored.
HIV - ANS-
Homeostasis - ANS- Maintenance of internal body conditions within an appropriate
range.
Hyperpolarisation - ANS- When the potential difference in the cell is more negative than
the resting potential due to excess potassium ions moving out since the membrane is
now highly permeable.
Acrosome reaction - ANS- Enzymes released by the acrosome digest the zona pellucida.
Action potential - ANS- The change in voltage from +40 to -70mV that occurs during
repolarisation.
Allopatric - ANS- Due to geographical isolation
Amniocentesis - ANS- A large needle is used to extract amniotic fluid, which
Antagonistic muscles - ANS- Muscle pairs arranged to work against each other to move
a joint.
Antibody - ANS-
Antigen presenting cells - ANS- Cells which display the antigens of the foreign cells on
their surface for other cells to recognise.
Apoptosis - ANS- Programmed cell death.
Auxins - ANS- Plant hormones that stimulate growth by causing cells to elongate.
Axon - ANS- This conducts an impulse away from the cell body.
B helper cells - ANS-
Basal Ganglia - ANS- A collection of neurones deep in each hemisphere which select
and initiate stored programs for movement.
Biodiversity - ANS- The diversity of plant and animal life in a particular habitat
Candidate Gene - ANS- A gene that is likely to cause a disease.
Carpentered world hypothesis - ANS- People who live in a world with many straight lines
and right angles tend to interpret obtuse and acute angles as right angles.
Cerebellum - ANS- This is responsible for balance and co-ordinating movement by
receiving information from the motor cortex, muscles and joints.
Chorionic villus sampling - ANS-
, Cones - ANS- Cones are cells in the retina which detect colour.
Corpus callosum - ANS- White matter made up mainly of axons. It provides connections
between the cortex and other brian structures. It also forms connections between the two
hemispheres of the brain.
Cortex - ANS- This is the grey folded matter around the brain.
Cortical reaction - ANS- Release of enzymes by the cortical granules which cause the
zona pellucida to thicken.
Dendrites - ANS- These conduct impulses towards the cell body.
Depolarisation - ANS- When the polarisation across the cell membrane is reversed,
making the inside of the axon positive and the outside negative.
DNA - ANS- Deoxyribose nucleic acid. Carries the genetic information for cells and some
viruses.
Drug targets - ANS- Molecules which can be altered by the binding of a drug.
Ecosystem - ANS- Organisms and their interactions with biotic and abiotic factors.
Excitatory synapse - ANS- These synapses make the postsynaptic membranes more
permeable to sodium ions.
Frontal lobe - ANS- This is concerned wth high reasoning, personality, forming
associations and ideas. It includes the primary motor cortex which stores information on
how to carry out movements.
Habitat - ANS- The natural environment in which a species lives.
Hippocampus - ANS- Where long term memory is stored.
HIV - ANS-
Homeostasis - ANS- Maintenance of internal body conditions within an appropriate
range.
Hyperpolarisation - ANS- When the potential difference in the cell is more negative than
the resting potential due to excess potassium ions moving out since the membrane is
now highly permeable.
