Biology B1.2 Coordination and Control

Biology B1.2 Coordination and Control

Responding to change

The nervous system uses electrical impulses to enable you to react quickly to your surroundings and coordinates where you are

Cells called receptors detect stimuli

Like all animal cells light receptors and other receptors have a nucleus, cytoplasm and cell membrane

Impulses from receptors pass along sensory neurones to the brain or the spinal cord. Impulses are sent along motor neurones from the brain to the effector organs.

Reflex actions

Some responses to stimuli are automatic and rapid and are called reflex actions

Reflex actions run every day bodily functions and help you to avoid danger

Reflex – rapid automatic response of the nervous system that does not involve conscious thought

Synapse – a gap between neurons where the transmission of information is chemical rather than electrical

Reflex arc – the sense organ, sensory neurone, relay neurone, motor neurone and effector organ which bring about a reflex action

Hormones and the menstrual cycle

Hormones control the release of an egg from the ovary and the build-up of…