1. Nervous system

2. Neuron

3. Briefly describe the following: Dendrites Axon Schwann cells Myelin sheath Nodes of Ranvier Neurilemma

4. How impulses are transmitted?

5. Division of the nervous system Central nervous system brain spinal cord Peripheral nervous system 1.Cranial nerves 2.Spinal nerves 3. Autonomic nervous system Sympathetic Parasympathetic

6. Central nervous system

7. Peripheral nervous system

8. Autonomic nervous system

9. Brain

10. Inner brain

11. Main parts of the brain Cerebrum Cerebellum Medulla oblongata Pons varolii Thalamus Hypothalamus

12. Cerebrum :controls voluntary actions, mental activities, sensory areas Cerebellum: controls movement, coordination, balance and posture Medulla oblongata: regulates heart and breathing rate, blood vessel diameter and reflex actions

13. Hypothalamus Hypothalamus controls: Autonomic nervous system Homeostasis(internal body balance) Salt/water balance, Hunger/thirst Body temperature Feelings associated with pain and aggression Sleep pattern

14. Pons varolii Transmits messages between the spinal cord, cerebellum and cerebrum Thalamus Coordinates messages from sensory organs

15. Meninges

16. Cerebrospinal fluid

18. Test for meningitis

19. Spinal cord Continuous with the medulla oblongata Protected by meninges Contains white matter(outside) and grey matter(inside) Provides communication between the brain and all parts of the body Involved with reflex actions

20. Spinal cord

22. Revision 1.What are meninges? 2.Name the meninges. 3.What is the function of cerebrospinal fluid? 4.What can trigger an epileptic fit? 5.What is cerebral palsy? 6.What causes meningitis? 7.What are the symptoms of meningitis? 8.What are the functions of cerebrum? 9.What are the functions of cerebellum? 10.What are the functions of medulla oblongata?

23. Peripheral NS Made up of all the nerves outside brain and spinal cord Type of nerves: sensory and motor Anna burnt her finger. Which type of nerve is responsible for informing her brain of this injury?

24. Peripheral NS 12 pairs of cranial nerves that originate from the brain They supply the muscles and sensory organs of the head and neck What are the 5 sensory organs and what receptors do they contain? Refer to book page 134

25. Sensory organs Eyes (light receptors - rods and cones) Ear (sound receptors) Tongue (taste receptors) Nose (smell receptors) Skin (pressure, touch and temperature receptors)

26. Peripheral NS 31 pairs of spinal nerves that originate from the spinal cord They are named according to the region of the spinal cord from which they emerge Label the diagram of the Spinal nerves(refer to book page 135)

27. OBJECTIVES Explain the sequence of the reflex arc. Draw a basic diagram of the reflex arc List the effects of the sympathetic and parasympathetic nervous system.

28. Reflex action Reflex action protects the body from danger The nerve impulse travels from the sensory organ to the spinal cord(bypassing the brain) to speed up an action

29. Reflex arc

30. Sequence of the reflex arc 1.Sensory nerve in the skin is stimulated 2. Sensory nerve travels to the spinal cord (by-passing the brain) 3. Inside the spinal cord interneuron takes the message from the sensory nerve and passes it to the motor nerve 4. Motor nerve travels from the spinal cord to the muscle and makes it move

31. Autonomic nervous system Controls all involuntary movements and actions of the internal organs Has two parts : 1. sympathetic –responsible for actions in times of stress, speeds up many body functions 2. parasympathetic-controls everyday activities helps to slow down body activities

32. Examples of sympathetic NS in action Increases heart rate Dilates blood vessels supplying heart and muscles Dilates pupils Stimulates sweat glands Dilates bronchi

33. Examples of parasympathetic NS in action Slows down heart rate Constricts blood vessels Constricts bronchi Constricts pupils

34. Objectives Revision for the mandatory test NEXT WEEK Name all the bones of the skeleton List the functions of the skeleton. Name the different parts of the NS. Describe reflex arc.