B1d

Question 1

describe the function of the 5 sensory organs.

Answer 1

eyes - receptors detect light
ears - receptors detect sound and position of the head
tongue - receptors detect chemicals in food
nose - receptors detect chemicals in air
skin - receptors detect touch, pressure, pain and temperature

Question 2

what is the cornea?

Answer 2

the front part of the tough outer coat, the sclera. It is convex, transparent and refracts light.

Question 3

what is binocular vision?

Answer 3

when signals from the 2 eyes reach the brain, they are superimposed and processed into a single picture with depth so we get a 3D picture and are able to judge distance well.

Question 4

what is concave?

Answer 4

short-sightedness

Question 5

what is convex?

Answer 5

long-sightedness

Question 6

what is a receptor?

Answer 6

they are a specialized group of cells that can detect changes (stimuli) in the environment. they are often found in the sensory organs eg eyes, ears.

Question 7

what is the optic nerve?

Answer 7

bundle of sensory neurones at the back of the eye. it carries impulses from the brain.