2. Co-ordination Electrical messenger Chemical messenger

3. Nervous System

4. Neuron

5. cytoplasm dendron cell membrane nucleus nucleus of cell which makes the myelin sheath axon direction of nerve impulses

6. Nerve fiber

7. Myelin Sheath Protection of nerve fiber Speed up impulse transfer

8. Rest Potential - ++++++ More + ion outside the nerone 1.Na K pump 2.K channel 3.Big - ions

9. Action potential

10. Action potential mechanism Depolarization  Stimulus to threshold  Na channel open  Inside nerone turn +ve. Repolarization  Potential rise inside nerone to max  Na channel close  More k channel open so hyperpolarised  Rest potential established by na k pump.

11. Na open K open Na close Refractory period

12.  ending of axon secretes a chemical which diffuses into synapse and stimulates the next neurone to pass on the impulse  the chemical is unstable and will be destroyed later synapse

13. Synapse

14. Synapse mechanism Go

15. Synaptic Cleft Neurotransmitter in vesicle release to cleft. It diffuse to another side and attach on surface receptor. Enzyme next to receptor break down. Transmitter

16. Brain

18. dorsal root ganglion dorsal root (sensory nerve) association neurone spinal cord ventral root (motor nerve) motor neurone sensory neurone effector (muscle) receptor (pain) Reflex arc : sensory, association, motor neurones

19. white matter grey matter central canal spinal cord spinal nerve

20. Peripheral Nervous System  consist of cranial nerves and spinal nerves  these nerves leave CNS and run out to every part of the body spinal nerve cranial nerve

21. Spinal Cell

22. Endocrine System Hormone concept Steroid concept Endocrine organs

23. Hormone concept Hormone is chemical messenger. It required a fitted receptor. Hormone attaching to receptor calls response.

24. Hormone concept 2 Hormone required blood vessel to transport to whole body.

25. Water soluble hormone Water soluble hormone only attach to membrane receptor.

26. Fat soluble hormone (steroid) Steroid can penetrate cell membrane and bind to internal receptor.

27. Example of steroids

28. Feedback mechanism Negative feedback reduce hormone production when effect of hormone expressed

29. Endocrine and Exocrine Blood vessel Secretary duct

30. Endocrine organs

31. Adrenal gland Adrenalin

32. Photo of adrenal gland

33. Pancreas Islet of langerhans

34. Thyroid gland

35. Pituitary gland

36. Control of endocrine system Hormone control hormone Nerve control hormone

37. Anterior and Posterior Pituitary gland AnteriorPosterior

38. Photo of pituitary gland