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Nerves, reflexes and the eye - Coggle Diagram
Nerves, reflexes and the eye
Nerves
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The CNS, central nervous system
The nervous system is made up of all the neurones (nerve cells) in your body, there are three types of neurone
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Between neurones, there are gaps called synapses.
When an electrical impulse reaches these gaps, the nerve releases neurotransmitters which carry the signal across the cap to next neurone where they trigger a new electrical impulse
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When receptors in sensory organs detect a stimulus they send an electrical impulse along sensory sensory neurones to the CNS
The CNS then sends electrical impulses to an effector along a motor neurone. The effector then responds accordingly
The nervous system transmits messages via electrical impulses therefore brings about very rapid responses
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The eye.
Features of the eye
CONJUNCTIVA: Lubricates and protects the surface of the eye
SCLERA: The tough outer layer that protects the eye
Cornea: Refracts the light into the eye, transparent, has no blood vessels so diffuses in oxygen from the air
IRIS: controls the diameter of the pupil and how much light enters the eye
LENS: Focuses the light onto the retina.
OPTIC NERVE: Carries impulses from receptors to the brain
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