AQA GCSE BIO
AQA GCSE
Biology Paper 2
This set has the following topics:
Growth and Regulation in Organisms
Cells and Biological Organization
Ecosystem Health and Human Influence
Sources of Genetic Variation
Applications and Ethics of Modern Genetics
Energy Flow in Ecosystems
Inheritance of Genetic Information
Matter Cycling in Ecosystems
Population Dynamics
Natural Selection: A Mechanism of Evolution
Evidence for Evolution
Factors Determining Variation or Distribution
Adaptation and Environmental Change
Energy Pathways in Living Systems
Speciation and Extinction
Evaluating Solutions for Biological Problems
Tools for Engineering Design
What is homeostasis?
The maintenance of a constant internal environment.
1|Page
,AQA GCSE BIO
1. What is a stimulus?
ANSWER: A change in your environment than requires a response. e.g Light, sound, touch, pressure,
pain, chemical or temperature.
2. What do the receptors do?
ANSWER: Detect the stimulus or change in environment.
3. What happens after the receptors?
ANSWER: Receptors send messages to the CNS via the sensory neuron.
4. What makes up the central nervous system?
ANSWER: The brain or spinal cord
5. What is an effector?
ANSWER: Muscles or glands that bring about a response.
6. What do the muscles and glands do in response to stimuli?
ANSWER: Muscles contract and glands secrete chemical substances(hormones).
7. What is a sensory neuron?
ANSWER: A neuron that carries information from the receptors to the CNS.
8. What is a relay neuron?
ANSWER: Neurons that carry impulses from the sensory neuron to the motor neuron.
9. What is a motor neuron?
ANSWER: Neurons that carry information from the CNS to the effectors.
10. What is the nervous system?
ANSWER: It is a system that allows you to react to your surroundings.
11. How do signals travel across a synapse?
ANSWER: The chemical or neurotransmitter diffuses across the synapse and binds to a complementary
receptor on the neuron (postsynaptic). This causes an electrical impulse to travel down the next neuron.
12. What is a synapse?
ANSWER: A gap between two neurons.
13. What is the thermoregulatory center of the brain?
ANSWER: Near the hypothalamus, monitors the temperature of blood.
14. Describe the stages in a reflex arc.
2|Page
,AQA GCSE BIO
ANSWER: Stimulus->Receptor->sensory neuron->CNS (relay neuron) -> motor neuron -> effector ->
response
15. Name responses that reduce body temperature.
ANSWER: Hairs lie flat, sweat and blood vessels get wider(vasodilation)
16. What happens during vasodilation?
ANSWER: The blood vessels supplying the skin dilate (widen). This helps to transfer energy to the
environment.
17. Name responses that increase body temperature.
ANSWER: Hairs stand up, no sweat, shivering and blood vessels constrict(vasoconstriction)
18. What happens during vasoconstriction?
ANSWER: The blood vessels supplying the skin constrict to close off the skins blood supply.
19. What is the body's core temp?
ANSWER: 37 degrees Celsius
20. What are hormones?
ANSWER: Chemical messengers that travel in the blood to target organs.
21. Compare and contrast the endocrine (hormone) system and the nervous system.
ANSWER: Nervous is faster acting than the endocrine system.
Hormones have longer lasting effects compared to electrical impulses. Nerves act on a very specific area
whereas hormones act more general.
22. What does the thyroid gland do?
ANSWER: Produces thyroxine which is involved in regulating metabolism.
23. What do the adrenal glands do?
ANSWER: Produce adrenaline which is used to prepare the body for fight or flight.
24. What is the role of the pancreas?
ANSWER: Produces glucagon and insulin which are involved in regulating glucose levels in the blood.
25. Name the hormone that is released if blood sugar is too high.
ANSWER: Insulin
26. What does insulin do?
ANSWER: It makes the liver convert glucose into glycogen. This causes blood glucose levels to decrease.
27. Name the hormone that is released if blood sugar is too low.
3|Page
, AQA GCSE BIO
ANSWER: Glucagon
28. What does glucagon do? HINT GLU-COSE-GONE
ANSWER: It makes the liver convert glycogen to glucose. This causes the blood glucose level to increase.
29. What is type I diabetes?
ANSWER: When the pancreas produces little or no insulin.
30. What is type II diabetes?
ANSWER: When a person becomes resistant to their own insulin. Being overweight can increase your
chances of type II diabetes.
31. How can type I diabetes be treated?
ANSWER: Insulin injections, limiting intake of foods rich is simple carbohydrates e.g. sugars and regular
exercise.
32. How can type II diabetes be treated?
ANSWER: It can be controlled by eating a carbohydrate-controlled diet and getting regular exercise.
33. What is the role of the kidneys.
ANSWER: Kidneys make urine by taking unwanted waste products out of your blood. They are involved
in selective reabsorption.
34. Name three things that are re-absorbed by the kidneys into the blood.
ANSWER: Glucose, water and ions.
35. Name three things that are removed from the body in the urine.
ANSWER: Urea, water and ions.
36. What is deamination?
ANSWER: Proteins (excess amino acids) cannot be stored by the body. Excess amino acids are converted
to fats and carbohydrates. This occurs in the liver.
37. What is produced as a waste product of deamination?
ANSWER: Ammonia is produced as a waste product. Ammonia is toxic so it is converted into urea in the
liver.
38. What hormone controls the amount of water absorbed by the kidneys?
ANSWER: ADH
39. What happens when the concentration of water in the blood is too low. I.e. the Blood is
MORE concentrated.
ANSWER: Receptors in the hypothalamus detects the water content is too low. The coordinator in the
brain receives the information and coordinates a response. The pituitary gland produces MORE (Anti-
4|Page
AQA GCSE
Biology Paper 2
This set has the following topics:
Growth and Regulation in Organisms
Cells and Biological Organization
Ecosystem Health and Human Influence
Sources of Genetic Variation
Applications and Ethics of Modern Genetics
Energy Flow in Ecosystems
Inheritance of Genetic Information
Matter Cycling in Ecosystems
Population Dynamics
Natural Selection: A Mechanism of Evolution
Evidence for Evolution
Factors Determining Variation or Distribution
Adaptation and Environmental Change
Energy Pathways in Living Systems
Speciation and Extinction
Evaluating Solutions for Biological Problems
Tools for Engineering Design
What is homeostasis?
The maintenance of a constant internal environment.
1|Page
,AQA GCSE BIO
1. What is a stimulus?
ANSWER: A change in your environment than requires a response. e.g Light, sound, touch, pressure,
pain, chemical or temperature.
2. What do the receptors do?
ANSWER: Detect the stimulus or change in environment.
3. What happens after the receptors?
ANSWER: Receptors send messages to the CNS via the sensory neuron.
4. What makes up the central nervous system?
ANSWER: The brain or spinal cord
5. What is an effector?
ANSWER: Muscles or glands that bring about a response.
6. What do the muscles and glands do in response to stimuli?
ANSWER: Muscles contract and glands secrete chemical substances(hormones).
7. What is a sensory neuron?
ANSWER: A neuron that carries information from the receptors to the CNS.
8. What is a relay neuron?
ANSWER: Neurons that carry impulses from the sensory neuron to the motor neuron.
9. What is a motor neuron?
ANSWER: Neurons that carry information from the CNS to the effectors.
10. What is the nervous system?
ANSWER: It is a system that allows you to react to your surroundings.
11. How do signals travel across a synapse?
ANSWER: The chemical or neurotransmitter diffuses across the synapse and binds to a complementary
receptor on the neuron (postsynaptic). This causes an electrical impulse to travel down the next neuron.
12. What is a synapse?
ANSWER: A gap between two neurons.
13. What is the thermoregulatory center of the brain?
ANSWER: Near the hypothalamus, monitors the temperature of blood.
14. Describe the stages in a reflex arc.
2|Page
,AQA GCSE BIO
ANSWER: Stimulus->Receptor->sensory neuron->CNS (relay neuron) -> motor neuron -> effector ->
response
15. Name responses that reduce body temperature.
ANSWER: Hairs lie flat, sweat and blood vessels get wider(vasodilation)
16. What happens during vasodilation?
ANSWER: The blood vessels supplying the skin dilate (widen). This helps to transfer energy to the
environment.
17. Name responses that increase body temperature.
ANSWER: Hairs stand up, no sweat, shivering and blood vessels constrict(vasoconstriction)
18. What happens during vasoconstriction?
ANSWER: The blood vessels supplying the skin constrict to close off the skins blood supply.
19. What is the body's core temp?
ANSWER: 37 degrees Celsius
20. What are hormones?
ANSWER: Chemical messengers that travel in the blood to target organs.
21. Compare and contrast the endocrine (hormone) system and the nervous system.
ANSWER: Nervous is faster acting than the endocrine system.
Hormones have longer lasting effects compared to electrical impulses. Nerves act on a very specific area
whereas hormones act more general.
22. What does the thyroid gland do?
ANSWER: Produces thyroxine which is involved in regulating metabolism.
23. What do the adrenal glands do?
ANSWER: Produce adrenaline which is used to prepare the body for fight or flight.
24. What is the role of the pancreas?
ANSWER: Produces glucagon and insulin which are involved in regulating glucose levels in the blood.
25. Name the hormone that is released if blood sugar is too high.
ANSWER: Insulin
26. What does insulin do?
ANSWER: It makes the liver convert glucose into glycogen. This causes blood glucose levels to decrease.
27. Name the hormone that is released if blood sugar is too low.
3|Page
, AQA GCSE BIO
ANSWER: Glucagon
28. What does glucagon do? HINT GLU-COSE-GONE
ANSWER: It makes the liver convert glycogen to glucose. This causes the blood glucose level to increase.
29. What is type I diabetes?
ANSWER: When the pancreas produces little or no insulin.
30. What is type II diabetes?
ANSWER: When a person becomes resistant to their own insulin. Being overweight can increase your
chances of type II diabetes.
31. How can type I diabetes be treated?
ANSWER: Insulin injections, limiting intake of foods rich is simple carbohydrates e.g. sugars and regular
exercise.
32. How can type II diabetes be treated?
ANSWER: It can be controlled by eating a carbohydrate-controlled diet and getting regular exercise.
33. What is the role of the kidneys.
ANSWER: Kidneys make urine by taking unwanted waste products out of your blood. They are involved
in selective reabsorption.
34. Name three things that are re-absorbed by the kidneys into the blood.
ANSWER: Glucose, water and ions.
35. Name three things that are removed from the body in the urine.
ANSWER: Urea, water and ions.
36. What is deamination?
ANSWER: Proteins (excess amino acids) cannot be stored by the body. Excess amino acids are converted
to fats and carbohydrates. This occurs in the liver.
37. What is produced as a waste product of deamination?
ANSWER: Ammonia is produced as a waste product. Ammonia is toxic so it is converted into urea in the
liver.
38. What hormone controls the amount of water absorbed by the kidneys?
ANSWER: ADH
39. What happens when the concentration of water in the blood is too low. I.e. the Blood is
MORE concentrated.
ANSWER: Receptors in the hypothalamus detects the water content is too low. The coordinator in the
brain receives the information and coordinates a response. The pituitary gland produces MORE (Anti-
4|Page
