AQA A LEVEL BIOLOGY PAPER 2 EXAM LATEST UPDATE 2025 ACTUAL
EXAM COMPLETE QUESTIONS AND CORRECT VERIFIED ANSWERS
|100%GUARANTEED PASS!!!
air spaces between them = rapid diffusion, long and narrow and are packed with
chloroplast the thin tissue of the leaf allows light to reach mesophyll - CORRECT
ANSWER-Name three advantages of mesophyll in the leaf
stroma in the fluid filled matrix - CORRECT ANSWER-where does the LIR occur?
100 stacked discs of thylakoids - CORRECT ANSWER-what is the grana?
chlorophyll absorbs light energy, excite electrons, move along carriers etc releasing
energy, used to join ADP and pi to form ATP, photolysis of water produces protons
electrons oxygen, NADP reduced by electrons - CORRECT ANSWER-describe the light
dependent reaction starting with Photolysis
electron is oxidised that reduces NADP, carries out series of redox reactions along the
electron transport chain that is then accepted by oxygen that is the terminal electron
receptor which oxidises NADPH back to NADP - CORRECT ANSWER-describe the
electron transport chain
contain both DNA and RNA so proteins can be manufactured quickly, thylakoid
membrane has a large SA for rapid DF and a network of proteins in the Grana to
maximise the absorbance of light - CORRECT ANSWER-name three advantages of the
structure of a chloraplast
CO2 combines 5 carbon ribulose-bi-phosphate to make 6 carbon molecule that is then
catalysed by rubisco to create two 3 phosphate glycerate molecules that are then
reduced via NADP and energy from ATP from LDR to triose phosphate that will
eventually turn into glucose, NADP reformed and goes back to LDR - CORRECT
ANSWER-describe the process of the LIR
natural = dead decomposing plants and artificial = mined from rocks t provides nutrients
to plant - CORRECT ANSWER-what is an example of a natural and artificial fertiliser?
the change of speed of direction in response to a stimulus - CORRECT ANSWER-what
is kinesis?
response to a stimulus where the direction is determined by the stimulus itself that is
moving the entire organism away or towards - CORRECT ANSWER-what is taxis?
,the detectable change in the external or internal environment - CORRECT ANSWER-
what is a stimulus?
IAA moves down a concentration gradient to the dark side of the shoot that then
increases the growth of that side to increase more than that of the light side so the plant
curves towards the light (phototrophism) ,in roots however, IAA inhibits growth and so
builds up on the underside of the root so the plant can more on the top so that it bends
towards gravity (gravitrophsim) - CORRECT ANSWER-what is the base movement of
IAA in plants and roots?
where the active transport of H+ ions from cytoplasm into the spaces in the cell wall
casuing the cell wall to become more plastic - CORRECT ANSWER-what is the acid
growth hypothesis?
brain and spinal cord - CORRECT ANSWER-What does the CNS consist of?
provides a voluntary/autonomic nervous system to provide a quick response with a
thought process to avoid overloading the brain so that it can carryout other actions at
the same time - CORRECT ANSWER-what does the PNS do?
stimulus - receptor - sensory neurone - coordinator - motor neurone - effector -
response - CORRECT ANSWER-name the pathway of the detection of a stimulus
chemoreceptors detect change in PH from the increase of CO2 in the blood that sends
a nerve impulse to the medulla oblongata, nerve impulse sent to SAN via the
sympathetic nervous system that initiates a wave of excitation across the atria, causing
it to contract, there is a short delay by non conducting tissue while the ventricles fill and
then the AVN releases another wave of excitation down the Purkinje tissue and bundles
of his to the apex of the heart that then contracts from the base up, the more impulse to
SAN = faster contraction of the heart to increase the heart rate, opposite = reduced
impulse via parasympathetic - CORRECT ANSWER-Describe the cardiac cycle with
reference to increase heart rate
Contraction within the muscle itself - CORRECT ANSWER-What does myogenic mean?
Pressure in PC is transfixed to chemical energy from mechanical pressure that causes
the stretch mediated sodium channels to become distorted and change shape to allow
sodium to diffuse down a concentration gradient that causes the opening of more
sodium ion channels to open on a neurone that stimulates the depolarisation of an axon
as a threshold has been met of the micro voltage - CORRECT ANSWER-Describe the
generating of a action potential via the pacinian corpuscle
Receptors in eye that found at the periphery, Detect low intensity light, have low visual
acuity, can't detect colour and have more than one linking to the same neurone -
CORRECT ANSWER-What are rods?
, Found in fovea, detects colour, only one connected to the same neurone so multiple
colours can be detected, detects high intensity light to produce rhodopsin - CORRECT
ANSWER-What is a cone?
Cell body, dendrons, axon, Schwann cell, myelin sheath and nodes of Ranvier -
CORRECT ANSWER-Name the six parts of a motor neurone?
Transport of hormones via blood plasma to target cells that is more slower and general -
CORRECT ANSWER-What is the hormonal system?
Transport of nervous impulses that is faster and in a more localised region - CORRECT
ANSWER-What is the nervous system?
Has a cell body in the middle of the axon that is a dorsal root ganglian - CORRECT
ANSWER-What is the distinguishable feature of a sensory neurone?
Long axon, cell body at the end, short den-trites - CORRECT ANSWER-Distinguishable
features of a motor neurone?
No threshold has been reached by stimulus so sodium potassium pump occurring
where 3 molecules of sodium go in and 1 potassium goes out via active transport -
CORRECT ANSWER-Describe what is happening in resting potential?
Neurone begins to depolarise as a stimulus has reached the threshold so sodium
voltage-gated channels open and an influx of sodium ions enters the neurone that
further depolarises the neurone, and as more sodium draws in, more gates open until
threshold has been reached and then begins action potential that repolarises the
neurone by closing the sodium voltage gate channels and opening the potassium
voltage gate channels until it has gone below resting potential where the refractory
period occurs and no action potential can occur (sodium-potassium pump) then the
process is repeated at each node of Ranvier until it reaches the synapse - CORRECT
ANSWER-Describe the process of a nervous impulse
The jumping of an action potential from node ranvier to node ranvier - CORRECT
ANSWER-What is saltatory conduction?
Diameter of a axon(larger = greater conductance), temperature (enzymes) and
myelinated sheath (no myelin sheath = less saltatory conduction so less action
potentials can occur along the same neurone = slower) - CORRECT ANSWER-What
affects the speed of a nervous impulse?
Temporal summation occurs when a high frequency of action potentials in the
presynaptic neuron invokes postsynaptic potentials that summate with each other -
CORRECT ANSWER-What is temporal summation?
EXAM COMPLETE QUESTIONS AND CORRECT VERIFIED ANSWERS
|100%GUARANTEED PASS!!!
air spaces between them = rapid diffusion, long and narrow and are packed with
chloroplast the thin tissue of the leaf allows light to reach mesophyll - CORRECT
ANSWER-Name three advantages of mesophyll in the leaf
stroma in the fluid filled matrix - CORRECT ANSWER-where does the LIR occur?
100 stacked discs of thylakoids - CORRECT ANSWER-what is the grana?
chlorophyll absorbs light energy, excite electrons, move along carriers etc releasing
energy, used to join ADP and pi to form ATP, photolysis of water produces protons
electrons oxygen, NADP reduced by electrons - CORRECT ANSWER-describe the light
dependent reaction starting with Photolysis
electron is oxidised that reduces NADP, carries out series of redox reactions along the
electron transport chain that is then accepted by oxygen that is the terminal electron
receptor which oxidises NADPH back to NADP - CORRECT ANSWER-describe the
electron transport chain
contain both DNA and RNA so proteins can be manufactured quickly, thylakoid
membrane has a large SA for rapid DF and a network of proteins in the Grana to
maximise the absorbance of light - CORRECT ANSWER-name three advantages of the
structure of a chloraplast
CO2 combines 5 carbon ribulose-bi-phosphate to make 6 carbon molecule that is then
catalysed by rubisco to create two 3 phosphate glycerate molecules that are then
reduced via NADP and energy from ATP from LDR to triose phosphate that will
eventually turn into glucose, NADP reformed and goes back to LDR - CORRECT
ANSWER-describe the process of the LIR
natural = dead decomposing plants and artificial = mined from rocks t provides nutrients
to plant - CORRECT ANSWER-what is an example of a natural and artificial fertiliser?
the change of speed of direction in response to a stimulus - CORRECT ANSWER-what
is kinesis?
response to a stimulus where the direction is determined by the stimulus itself that is
moving the entire organism away or towards - CORRECT ANSWER-what is taxis?
,the detectable change in the external or internal environment - CORRECT ANSWER-
what is a stimulus?
IAA moves down a concentration gradient to the dark side of the shoot that then
increases the growth of that side to increase more than that of the light side so the plant
curves towards the light (phototrophism) ,in roots however, IAA inhibits growth and so
builds up on the underside of the root so the plant can more on the top so that it bends
towards gravity (gravitrophsim) - CORRECT ANSWER-what is the base movement of
IAA in plants and roots?
where the active transport of H+ ions from cytoplasm into the spaces in the cell wall
casuing the cell wall to become more plastic - CORRECT ANSWER-what is the acid
growth hypothesis?
brain and spinal cord - CORRECT ANSWER-What does the CNS consist of?
provides a voluntary/autonomic nervous system to provide a quick response with a
thought process to avoid overloading the brain so that it can carryout other actions at
the same time - CORRECT ANSWER-what does the PNS do?
stimulus - receptor - sensory neurone - coordinator - motor neurone - effector -
response - CORRECT ANSWER-name the pathway of the detection of a stimulus
chemoreceptors detect change in PH from the increase of CO2 in the blood that sends
a nerve impulse to the medulla oblongata, nerve impulse sent to SAN via the
sympathetic nervous system that initiates a wave of excitation across the atria, causing
it to contract, there is a short delay by non conducting tissue while the ventricles fill and
then the AVN releases another wave of excitation down the Purkinje tissue and bundles
of his to the apex of the heart that then contracts from the base up, the more impulse to
SAN = faster contraction of the heart to increase the heart rate, opposite = reduced
impulse via parasympathetic - CORRECT ANSWER-Describe the cardiac cycle with
reference to increase heart rate
Contraction within the muscle itself - CORRECT ANSWER-What does myogenic mean?
Pressure in PC is transfixed to chemical energy from mechanical pressure that causes
the stretch mediated sodium channels to become distorted and change shape to allow
sodium to diffuse down a concentration gradient that causes the opening of more
sodium ion channels to open on a neurone that stimulates the depolarisation of an axon
as a threshold has been met of the micro voltage - CORRECT ANSWER-Describe the
generating of a action potential via the pacinian corpuscle
Receptors in eye that found at the periphery, Detect low intensity light, have low visual
acuity, can't detect colour and have more than one linking to the same neurone -
CORRECT ANSWER-What are rods?
, Found in fovea, detects colour, only one connected to the same neurone so multiple
colours can be detected, detects high intensity light to produce rhodopsin - CORRECT
ANSWER-What is a cone?
Cell body, dendrons, axon, Schwann cell, myelin sheath and nodes of Ranvier -
CORRECT ANSWER-Name the six parts of a motor neurone?
Transport of hormones via blood plasma to target cells that is more slower and general -
CORRECT ANSWER-What is the hormonal system?
Transport of nervous impulses that is faster and in a more localised region - CORRECT
ANSWER-What is the nervous system?
Has a cell body in the middle of the axon that is a dorsal root ganglian - CORRECT
ANSWER-What is the distinguishable feature of a sensory neurone?
Long axon, cell body at the end, short den-trites - CORRECT ANSWER-Distinguishable
features of a motor neurone?
No threshold has been reached by stimulus so sodium potassium pump occurring
where 3 molecules of sodium go in and 1 potassium goes out via active transport -
CORRECT ANSWER-Describe what is happening in resting potential?
Neurone begins to depolarise as a stimulus has reached the threshold so sodium
voltage-gated channels open and an influx of sodium ions enters the neurone that
further depolarises the neurone, and as more sodium draws in, more gates open until
threshold has been reached and then begins action potential that repolarises the
neurone by closing the sodium voltage gate channels and opening the potassium
voltage gate channels until it has gone below resting potential where the refractory
period occurs and no action potential can occur (sodium-potassium pump) then the
process is repeated at each node of Ranvier until it reaches the synapse - CORRECT
ANSWER-Describe the process of a nervous impulse
The jumping of an action potential from node ranvier to node ranvier - CORRECT
ANSWER-What is saltatory conduction?
Diameter of a axon(larger = greater conductance), temperature (enzymes) and
myelinated sheath (no myelin sheath = less saltatory conduction so less action
potentials can occur along the same neurone = slower) - CORRECT ANSWER-What
affects the speed of a nervous impulse?
Temporal summation occurs when a high frequency of action potentials in the
presynaptic neuron invokes postsynaptic potentials that summate with each other -
CORRECT ANSWER-What is temporal summation?
