Welcome it is a great day to learn about the Brain

1. Welcome it is a great day to learn about the Brain

2. What does the Brain do? • Jot down EVERYTHING your brain does • Okay list about 10 things

3. We are going to start small and go big

4. Neurons: The Building Blocks of the Nervous System

5. Nervous System • The electrochemical communication system of the body • Sends messages from the brain to the body for movement • Brings information to the brain from the senses

6. Neuron • The basic building block of the nervous system -- a nerve cell • Neurons perform three basic tasks • Receive information • Carry the information • Pass the information on to the next neuron

7. Types of Neurons Sensory Motor Interneuron's

8. Sensory Neurons • INPUT Fromsensory organs to the brain and spinal cord Brain Drawing shows a somatic neuron Sensory Neuron Spinal Cord

9. Brain Sensory Neuron Spinal Cord Motor Neuron Motor Neurons • OUTPUTFrom the brain and spinal cord to the muscles and glands

10. Brain Sensory Neuron Spinal Cord Motor Neuron Interneuron's • Interneurons carry information between other neurons only found in the brain and spinal cord

11. The Basic Parts of a Neuron

12. What are the primary parts of a typical neuron? • Nervous system • Neurons • Dendrites • Soma • Axon • Terminal branches of Axon • Myelin Sheath

13. The Basic Parts of a Neuron

14. Parts of the Neuron

15. A. Dendrites • Thin, branching fibers lined with receptors at which the dendrite receives information from other neurons.

16. Parts of the Neuron - Dendrites

17. B. Cell Body/Soma • Contains the nucleus and other parts of the cell needed to sustain life

18. Parts of the Neuron - Soma

19. C. Axon • Carries the message across the neuron

20. Parts of the Neuron - Axon

21. D. Myelin Sheath • An insulating, fatty covering around the axon that speeds neural transmissions. Axons that are myelinated appear white. Known as “white matter.”

22. Parts of the Neuron – Myelin Sheath

23. E. Axon Terminal Buttons • The branched end of the axon that contains neurotransmitters

24. Parts of the Neuron - Terminals

25. Time to Move • Locate the person furthest from you • Go to that person • Introduce yourself

26. Pick an A and D A = Axon D= Dendrite With your partner explain the relationship between neurons

27. Neuron

28. Neuron

29. Neural Transmission

31. Neural Communication: The Neural Impulse

32. Action Potential • A brief electrical charge that travels down the axon of the neuron. • A neural impulse • Considered an “on” condition of the neuron

33. Refractory Period • The “recharging phase” when a neuron, after firing, cannot generate another action potential • Once the refractory period is complete the neuron can fire again

34. Resting Potential • The state of a neuron when it is at rest and capable of generating an action potential • The neuron is set and ready to fire

38. Neuron firing like a Toilet • Like a Neuron, a toilet has an action potential. When you flush, an “impulse” is sent down the sewer pipe

39. Neuron firing like a Toilet 2. Like a neuron, a toilet has a refractory period. There is a short delay after flushing when the toilet cannot be flushed again because the tank is being refilled

40. Neuron firing like a Toilet • Like a Neuron, a toilet has a resting potential. The toilet is “charged” when there is water in the tank and it is capable of being flushed again • Like a Neuron, a toilet operates on the all-or-none principle – it always flushes with the same intensity, no matter how much force you apply to the handle

41. All-or-None Principle • The principle that if a neuron fires it will always fire at the same intensity • All action potentials are of the same strength. • A neuron does NOT fire at 30%, 45% or 90% but at 100% each time it fires.

42. Communication Between Neurons Module 7: Neural and Hormonal Systems

43. Synapse • The space between the terminal buttons on one neuron and dendrites of the next neuron

45. Neurotransmitters • Chemicals contained in the terminal buttons that enable neurons to communicate. Neurotransmitters fit into receptor sites on the dendrites of neurons like a key fits into a lock.

46. Neurotransmitters

47. Neurotransmitters • A chemical messenger that travels across the synapse from one neuron to the next • Can influence whether the second neuron will generate an action potential or not