Exam (elaborations) AQA GCSE Biology Paper 2

AQA GCSE BIOLOGY Paper 2 MARK
SCHEME(8461/2F: Foundation Tier)2024

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,What is homeostasis? - CORRECT ANSWERS-The maintenance of a constant internal
environment.

What is a stimulus? - CORRECT ANSWERS-A change in your environment than
requires a response. e.g Light, sound, touch, pressure, pain, chemical or temperature.

What do the receptors do? - CORRECT ANSWERS-Detect the stimulus or change in
environment.

What happens after the receptors? - CORRECT ANSWERS-Receptors send messages
to the CNS via the sensory neurone.

What makes up the central nervous system? - CORRECT ANSWERS-The brain or
spinal cord

What is an effector? - CORRECT ANSWERS-Muscles or glands that bring about a
response.

What do the muscles and glands do in response to stimuli? - CORRECT ANSWERS-
Muscles contract and glands secrete chemical substances(hormones).

What is a sensory neurone? - CORRECT ANSWERS-A neurone that carry information
from the receptors to the CNS.

What is a relay neurone? - CORRECT ANSWERS-Neurones that carry impulses from
the sensory neurone to the motor neurone.

What is a motor neurone? - CORRECT ANSWERS-Neurones that carry information
from the CNS to the effectors.

What is the nervous system? - CORRECT ANSWERS-It is a system that allows you to
react to your surroundings.

How do signals travel across a synapse? - CORRECT ANSWERS-The chemical or
neurotransmitter diffuses across the synapse and binds to a complementary receptor on
the neurone (postsynaptic). This causes an electrical impulse to travel down the next
neurone.

What is a synapse? - CORRECT ANSWERS-A gap between two neurones.

What is the thermoregulatory centre of the brain? - CORRECT ANSWERS-Near the
hypothalamus, monitors the temperature of blood.

Describe the stages in a reflex arc. - CORRECT ANSWERS-Stimulus->Receptor-
>sensory neurone->CNS (relay neurone) -> motor neurone -> effector -> response

, Name responses that reduce body temperature. - CORRECT ANSWERS-Hairs lie flat,
sweat and blood vessels get wider(vasodilation)

What happens during vasodilation? - CORRECT ANSWERS-The blood vessels
supplying the skin dilate (widen). This helps to transfer energy to the environment.

Name responses that increase body temperature. - CORRECT ANSWERS-Hairs stand
up, no sweat, shivering and blood vessels constrict(vasoconstriction)

What happens during vasoconstriction? - CORRECT ANSWERS-The blood vessels
supplying the skin constrict to close off the skins blood supply.

What is the body's core temp? - CORRECT ANSWERS-37 degrees Celsius

What are hormones? - CORRECT ANSWERS-Chemical messengers that travel in the
blood to target organs.

Compare and Contrast the endocrine (hormone) system and the nervous system. -
CORRECT ANSWERS-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.

What does the thyroid gland do? - CORRECT ANSWERS-Produces thyroxine which is
involved in regulating metabolism.

What do the adrenal glands do? - CORRECT ANSWERS-Produce adrenaline which is
used to prepare the body for fight or flight.

What is the role of the pancreas? - CORRECT ANSWERS-Produces glucagon and
insulin which are involved in regulating glucose levels in the blood.

Name the hormone that is released if blood sugar is too high. - CORRECT ANSWERS-
Insulin

What does insulin do? - CORRECT ANSWERS-It makes the liver convert glucose into
glycogen. This causes blood glucose levels to decrease.

Name the hormone that is released if blood sugar is too low. - CORRECT ANSWERS-
Glucagon

What does glucagon do? HINT GLU-COSE-GONE - CORRECT ANSWERS-It makes
the liver convert glycogen to glucose. This causes the blood glucose level to increase.

What is type I diabetes? - CORRECT ANSWERS-When the pancreas produces little or
no insulin.