Why do you need iodine in your diet?

Which parts of the body form the central nervous system?

Give three examples of reflex actions.

State whether coughing is a voluntary action or reflex action.

Fill in the following blanks with suitable words:

(a) The two examples of effectors are .................and .....................

(b) Our..................system allows us to react to our surroundings. Information from receptors passes along.................neurons to our brain. Our brain sends impulses along...........neurons to our muscles.

(c) A neuron which carries an impulse to the brain is called a .................... neuron.

(d) The neuron which carries a message for action to a muscle or gland is known as a.................... neuron.