2.2 Reflex Actions Flashcards
Give the sequence of events involved in a reflex action (6)
A receptor detect a stimulus eg pain, light
A sensory neuron transmits the impulse to the CNS
A relay neuron passes the impulse on
A motor neuron is stimulated fghf
The impulse passes to an effector (a muscle or gland)
Action is taken (the response)
What is at eh junction between two neurons?
A synapse
What transmits an impulse across the gap between two neurons?
Chemicals
What is the function of a relay neuron?
It links the sensory and motor neurons.
How many types of neurons are there? Name them.
3, Sensory, relay, motor
What is a neuron?
A cell in the nervous system which carries electrical impulses around the body
What is a reflex action?
A rapid, automatic response to a stimulus
When a stimulus is detected is the information transmitted to the brain by chemical or electrical messages?
Both, electrical through the neurons and chemical across the gaps between the neurons (the synapse)
What is a reflex arc?
The sequence from receptor to effector.
What is an effector (in terms of reflex actions)
the part of the body which actually responds to the stimulus, that is a muscle or a gland.
