AQA GCSE Biology Paper 2 with correct answers stated 2024

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.