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What is homeostasis?
The maintenance of a constant internal environment.
What is a stimulus?
A change in your environment than requires a response. e.g Light, sound, touch, pressure, pain, chemical or temperature.
What do the receptors do?
Detect the stimulus or change in environment.
What happens after the receptors?
Receptors send messages to the CNS via the sensory neurone.
What makes up the central nervous system?
The brain or spinal cord
What is an effector?
Muscles or glands that bring about a response.
What do the muscles and glands do in response to stimuli?
Muscles contract and glands secrete chemical substances(hormones).
What is a sensory neurone?
A neurone that carry information from the receptors to the CNS.
What is a relay neurone?
Neurones that carry impulses from the sensory neurone to the motor neurone.
What is a motor neurone?
Neurones that carry information from the CNS to the effectors.
What is the nervous system?
It is a system that allows you to react to your surroundings.
How do signals travel across a synapse?
The chemical or neurotransmitter diffuses across the synapse and binds to a complementary receptor on the neurone (postsynaptic). This causes an elect...
What is a synapse?
A gap between two neurones.
What is the thermoregulatory centre of the brain?
Near the hypothalamus, monitors the temperature of blood.
Describe the stages in a reflex arc.
Stimulus->Receptor->sensory neurone->CNS (relay neurone) -> motor neurone -> effector -> response
Name responses that reduce body temperature.
Hairs lie flat, sweat and blood vessels get wider(vasodilation)
