AQA Biology Unit 6 Questions with Correct Answers Latest Update 2025
Kinesis - Answers behaviour that results in a change in the rate of random movement of an animal,
where an organism either increases or decreases the number of turns it makes.
Stimulus - Answers a change in the internal or external environment of an organism.
Taxis - Answers behaviour that results in a change in direction of an organism, where the organism
either moves towards or away from a stimulus.
Auxin - Answers plant growth hormone.
Gravitropism - Answers plant growth in response to gravity.
Indoleacetic acid (IAA) - Answers a type of auxin.
Phototropism - Answers plant growth in response to light.
Stimulus - Answers a change in the internal or external environment of an organism.
Tropism - Answers a growth movement response of part of a plant in response to a stimulus.
Axon - Answers long structure extending that conducts impulses away from the cell body of a neurone.
Central nervous system (CNS) - Answers nervous tissue made up of the brain and spinal cord.
Dendrite - Answers branch-like structures that conduct impulses towards the cell body.
Effector - Answers an organ that brings about a response to a stimulus.
Impulse - Answers a series of action potentials.
Motor neurone - Answers neurone that transmits impulses from a relay neurone (in the central nervous
system) to an effector.
Myelin - Answers a fatty substance found in the membranes of Schwann cells.
Myelin sheath - Answers a collection of Schwann cells wrapped around the axon of a neurone.
Neurone - Answers a nerve cell..
Node of Ranvier - Answers a gap in the myelin sheath where the axon is exposed.
Peripheral nervous system - Answers nervous tissue outside of the brain and spinal cord.
Receptor - Answers a cell capable of detecting a stimulus.
Relay neurone - Answers neurone that transmits impulses between sensory neurones and motor
neurones, or between other relay neurones; found in the CNS.
, Schwann cell - Answers cell that wraps around the axon of a neurone and forms the myelin sheath.
Sensory neurone - Answers neurone that transmits impulses from a receptor to a relay neurone (in the
central nervous system).
Synaptic knob/axon terminal - Answers end of the axon that synapses with the dendrites or cell body of
another neurone or with an effector.
Axon - Answers long structure extending that conducts impulses away from the cell body of a neurone.
Central nervous system (CNS) - Answers nervous tissue made up of the brain and spinal cord.
Dendrite - Answers branch-like structures that conduct impulses towards the cell body.
Depolarisation - Answers temporary reversal of charge in the membrane potential of a neurone caused
by a rapid influx of sodium ions, and resulting in an action potential.
Hyperpolarisation - Answers when the membrane potential of a neurone becomes more negative than
the resting potential, caused by either an excess efflux of potassium ions after repolarisation, or an influx
of negatively charged ions such as chloride ions.
Impulse - Answers a series of action potentials down the axon of a neurone.
Membrane potential - Answers the difference in charge across a membrane.
Myelin - Answers a fatty substance found in the membranes of Schwann cells.
Myelin sheath - Answers a collection of Schwann cells wrapped around the axon of a neurone.
Node of Ranvier - Answers a gap in the myelin sheath where the axon is exposed.
Refractory period - Answers time after an action potential has been stimulated, during which no new
action potential can occur.
Repolarisation - Answers return of membrane potential of a neurone to the resting charge, caused by an
efflux of potassium ions.
Resting potential - Answers the membrane potential of a neurone when no impulse is being sent.
Peripheral nervous system - Answers nervous tissue outside of the brain and spinal cord.
Saltatory conduction - Answers the propagation/movemnt of an impulse down a myelinated axon as a
result of action potentials only being generated in the Nodes of Ranvier.
Schwann cell - Answers cell that wraps around the axon of a neurone and forms the myelin sheath.
Sodium-potassium pump - Answers carrier protein capable of actively transporting three sodium ions
out of a cell the two potassium ions into a cell using the energy in ATP.
Kinesis - Answers behaviour that results in a change in the rate of random movement of an animal,
where an organism either increases or decreases the number of turns it makes.
Stimulus - Answers a change in the internal or external environment of an organism.
Taxis - Answers behaviour that results in a change in direction of an organism, where the organism
either moves towards or away from a stimulus.
Auxin - Answers plant growth hormone.
Gravitropism - Answers plant growth in response to gravity.
Indoleacetic acid (IAA) - Answers a type of auxin.
Phototropism - Answers plant growth in response to light.
Stimulus - Answers a change in the internal or external environment of an organism.
Tropism - Answers a growth movement response of part of a plant in response to a stimulus.
Axon - Answers long structure extending that conducts impulses away from the cell body of a neurone.
Central nervous system (CNS) - Answers nervous tissue made up of the brain and spinal cord.
Dendrite - Answers branch-like structures that conduct impulses towards the cell body.
Effector - Answers an organ that brings about a response to a stimulus.
Impulse - Answers a series of action potentials.
Motor neurone - Answers neurone that transmits impulses from a relay neurone (in the central nervous
system) to an effector.
Myelin - Answers a fatty substance found in the membranes of Schwann cells.
Myelin sheath - Answers a collection of Schwann cells wrapped around the axon of a neurone.
Neurone - Answers a nerve cell..
Node of Ranvier - Answers a gap in the myelin sheath where the axon is exposed.
Peripheral nervous system - Answers nervous tissue outside of the brain and spinal cord.
Receptor - Answers a cell capable of detecting a stimulus.
Relay neurone - Answers neurone that transmits impulses between sensory neurones and motor
neurones, or between other relay neurones; found in the CNS.
, Schwann cell - Answers cell that wraps around the axon of a neurone and forms the myelin sheath.
Sensory neurone - Answers neurone that transmits impulses from a receptor to a relay neurone (in the
central nervous system).
Synaptic knob/axon terminal - Answers end of the axon that synapses with the dendrites or cell body of
another neurone or with an effector.
Axon - Answers long structure extending that conducts impulses away from the cell body of a neurone.
Central nervous system (CNS) - Answers nervous tissue made up of the brain and spinal cord.
Dendrite - Answers branch-like structures that conduct impulses towards the cell body.
Depolarisation - Answers temporary reversal of charge in the membrane potential of a neurone caused
by a rapid influx of sodium ions, and resulting in an action potential.
Hyperpolarisation - Answers when the membrane potential of a neurone becomes more negative than
the resting potential, caused by either an excess efflux of potassium ions after repolarisation, or an influx
of negatively charged ions such as chloride ions.
Impulse - Answers a series of action potentials down the axon of a neurone.
Membrane potential - Answers the difference in charge across a membrane.
Myelin - Answers a fatty substance found in the membranes of Schwann cells.
Myelin sheath - Answers a collection of Schwann cells wrapped around the axon of a neurone.
Node of Ranvier - Answers a gap in the myelin sheath where the axon is exposed.
Refractory period - Answers time after an action potential has been stimulated, during which no new
action potential can occur.
Repolarisation - Answers return of membrane potential of a neurone to the resting charge, caused by an
efflux of potassium ions.
Resting potential - Answers the membrane potential of a neurone when no impulse is being sent.
Peripheral nervous system - Answers nervous tissue outside of the brain and spinal cord.
Saltatory conduction - Answers the propagation/movemnt of an impulse down a myelinated axon as a
result of action potentials only being generated in the Nodes of Ranvier.
Schwann cell - Answers cell that wraps around the axon of a neurone and forms the myelin sheath.
Sodium-potassium pump - Answers carrier protein capable of actively transporting three sodium ions
out of a cell the two potassium ions into a cell using the energy in ATP.
