Human nervous system

This structure detects a stimulus

• Sensory neurone

• Receptor

• Synapse

• Effector

This structure carries an impulse to the effector

• Sensory neurone

• Motor neurone

• Relay neurone

• Muscle

This part of a neurone contains the nucleus

• Dendrite

• Axon

• Myelin sheath

• Cell body

This chemical is released at a synapse

• Hormone

• Neurotransmitter

• Impulse

• Enzyme

Which of the following is an example of a reflex action?

• Running away from a dog

• Jumping to catch a ball

• Releasing saliva when you smell tasty food

• Raising your hand to catch a ball

Which is the effector when you move into a dark room on a sunny day?

• Pupil

• Radial iris muscle

• Circular iris muscle

Which muscle is used in accommodation in the eye?

• Circular

• Radial

• Ciliary

Which structure refracts light when it enters the eye?

• Lens

• Pupil

• Retina

• Sclera

Which of these structures contains photoreceptors?

• Retina

• Cornea

• Lens

• Optic nerve

The correct name for short sightedness is...

• Myopia

• Hyperopia

• Hypopia