Stimulates seed germination, stem growth and flowering.

Receptors send messages to the CNS via the sensory neurone.

At the back, responsible for muscle contraction & balance

Contains receptor cells called rods and cones. These are sensitive to colour and light intensity.

The time it takes to respond to a stimulus

Control the shape of the lens

Chemical messengers that travel in the blood to target organs.

It is a system that allows you to react to your surroundings.

In the testes.

Male and female condom, diaphragm, spermicide

In dim light a reflex is triggered to make the pupil dilate. The CIRCULAR muscles RELAX and the RADIAL muscles CONTRACT.

Headaches and nausea. Still contract STIs.

FSH and LH are given to a woman to help eggs mature and release. Eggs are then collected from a woman's ovaries. The eggs are fertilised in a lab with...