1. Remember: A nerve cell, also called a neuron, sends nerve impulses, (electrical signals) to: ●other nerve cells ● to muscles

2. 2 TYPES OF MUSCLES A.VOLUNTARY MUSCLES: a.WE CAN CONTROL THESE MUSCLES B.INVOLUNTARY MUSCLES: a. WE CAN NOT CONTROL THESE MUSCLES b.THESE MUSCLES ARE AUTOMATIC

3. THE 5 SENSE ORGANS: I.Eyes A.Our eyes let us see. B.They give us sight. II.Ears A.Our ears let us hear. B.They help us listen. III.Skin A.Our skin lets us touch. B.It helps us feel. IV.Tongue A.Our tongue lets us taste. B.It helps us eat. V.Nose A.Our nose lets us smell. B.It helps us breathe.

4. 1.The CNS (central nervous system) and voluntary muscles: Voluntary muscles: ●These are muscles we can move. ●We decide when to make them move. ●We decide when to make them stop. When we decide to do something, we use our brain. (messenger) nerve impulse As a result, nerve impulses (electrical signals) for voluntary movements travel from the brain to muscles. make a decision voluntary movement nerve impulses

5. 1.The CNS (central nervous system) and involuntary muscles: Involuntary muscles (automatic movements): ●These are muscles we don’t control. ●We don’t decide when to make them move. ●We don’t decide when to make them stop. When our body carries out involuntary movements, we don’t have to make a decision. Involuntary movements are automatic. As a result, nerve impulses (electrical signals) for involuntary movements travel from the spinal cord to muscles. involuntary movement (reflex) nerve impulses