An object that can focus light rays. In the eye, it brings light rays to focus on the retina.

Occurs when light travels from one transparent medium to another, causing a change in direction.

The process of bringing light rays together to converge at a single point creating a clear image.

The point where rays of light meet after passing through a lens.

An involuntary, fast neural response to a situation.

The human eye

Biology

The human nervous system

Neurones and synapses

Human reaction time: practical

The structure and function of a reflex arc

Common defects of the human eye

The human brain

Pupils will learn how hormones and glands of the human endocrine system enable us to coordinate and control changes in our bodies.

Pupils learned how substances essential for chemical reactions in living cells, and the products of the reactions, are transported into, around and out of the human body, and the implications of surface area:volume ratio.

This unit explores the structure and function of the nervous system, including the CNS, reflex arcs, and the eye. It covers brain structure, common eye defects, and the challenges in treating nervous system damage. It also addresses ethical considerations.

Coordination and control: the human nervous system

The ciliary muscles contract or relax to change the shape of the ...

The lens is short and fat in shape beacuse the ciliary muscles contract.

The lens is short and fat in shape because the ciliary muscles relax.

The lens is long and thin in shape because the ciliary muscles contract.

The lens is long and thin in shape because the ciliary muscles relax.

Which statement correctly describes the lens and ciliary muscles if you are focusing on an object that is far away?

Put the following steps in order to describe how we see.

Which of the following responses happen to the eye in the dark?

Lucas: We can shine a bright torch in someones eyes to see the pupil change

Sofia: We can sit in the dark then turn on a light and see how the pupil changes

Sam: We can look at different peoples eyes

Jacob: We can watch someones eyes to see if it changes

How can we investigate the effect of light on pupil size?

True or false? The reflex arc is a lengthened neural pathway.

The stimulus is detected by the receptor.

A nerve impulse is sent along the sensory neurone.

In the spinal cord, a relay neurone transfers the impulse to the motor neurone.

This triggers the effector muscle to contract and produce the response.

Put the steps of this reflex arc in the correct order.

Sec_Sci_AW_192_2

What organ is **not** initially involved in a reflex response?

By triggering the sensory neurone in the reflex arc.

By triggering the relay neurone in the reflex arc.

By triggering the motor neurone in the reflex arc.

How can the brain override some reflex responses?

The human eye

Lesson outcome