Coordination and Response Flashcards
What do receptors detect?
Stimuli
What do effectors produce?
a response
Where are receptors found?
In the sense organs (eyes, ears, nose, tongue, skin)
What are the three types of neurone?
sensory
relay
motor
What does the central nervous system consist of?
the brain and the spinal chord
What is the job of the CNS?
To coordinate the response
How do neurones transmit information?
Using high speed electrical impulses
What are reflexes?
automatic responses to certain stimuli
What is the route taken by the information in a reflex called?
a reflex arc
Name the reflex arc processes
Stimulus Receptor Sensory Neurone Relay Neurone Motor Neurone Effector Response
What happens when a stimulus is detected by receptors?
an impulse is sent along a sensory neurone to the CNS
What is the gap between two neurones called?
a synapse
An individual nerve cell is a…
neurone
A bundle of neurones is a…
nerve
Messages are passed across synapses using…
chemicals (chemical transmitters)
What does the conjunctiva do?
lubricates and protects the surface of the eye
What does the cornea do?
refracts light into the eye
It is transparent and has no blood vessels to supply it with oxygen, so oxygen diffuses in from the outer surface
What does the iris do?
controls the diameter of the pupil
therefore how much light enters the eye
What does the lens do?
focuses light onto the retina
What is the retina covered in?
light receptors called rods and cones
What are rods?
A light receptor that is sensitive in dim light but can’t sense colour
What are cones?
A light receptor that is sensitive to colours but not dim light
Where are most cones found?
The fovea
What are hormones?
chemicals released directly into the blood
What are hormones carried in?
blood plasma