IGCSE 0645 B9.1 9.2

The diagram shows a cell.

What type of cell is shown?

• ciliated cell

• motor neurone

• relay neurone

• sensory neurone

The diagram shows a neurone carrying an impulse.

Which row describes the type of neurone and the direction of impulse?

Which choice describes the type of neurone and the direction of impulse?

• type of neurone = motor; direction of impulse = towards the spinal cord

• type of neurone = motor; direction of impulse = away from the spinal cord

• type of neurone = sensory; direction of impulse = towards the spinal cord

• type of neurone = sensory; direction of impulse = away from the spinal cord

The diagram shows a section through part of the human eye.

When a person looks at an object which is close to their eye, which of the following takes place?

• suspensory ligaments slacken; lens becomes fatter

• suspensory ligaments slacken; lens becomes thinner

• suspensory ligaments tighten; lens becomes fatter

• suspensory ligaments tighten; lens becomes thinner

A bright light suddenly shines into a person’s eyes.

What happens?

• The lenses become more concave.

• The lenses become more convex.

• The pupils become larger.

• The pupils become smaller.

The diagram shows the human nervous system.

Which letter indicates a part of the central nervous system?

• A

• B

• C

• D

The diagram shows the muscles which control the size of the pupil in an eye.

How do the muscles make the pupil larger?

• circular muscles contract; radial muscles contract.

• circular muscles contract; radial muscles relax.

• circular muscles relax; radial muscles contract.

• circular muscles relax; radial muscles relax.

Which list describes the correct sequence of a simple reflex arc?

• A receptor, relay neurone, motor neurone, sensory neurone, effector

• B receptor, relay neurone, sensory neurone, motor neurone, effector

• C receptor, sensory neurone, motor neurone, relay neurone, effector

• D receptor, sensory neurone, relay neurone, motor neurone, effector

The diagram shows a simple reflex arc.

Which labelled part is the sensory neurone?

• A

• B

• C

• D

Some structures in the eye are listed.

1 cornea

2 iris

3 lens

4 retina

Which structures contain light receptors?

• 1, 2 and 3

• 2, 3 and 4

• 2 and 4 only

• 4 only

Which statement about light receptors in the retina of a normal human eye is correct?

• The cones only work in dim light

• The rods are found in the fovea.

• The cones can detect colours of light

• There are three types of rod.