1. Biological Basis of Behavior So our brain chemistry and make-up is responsible for our behavior?

2. The Nervous System I. The Neuron -structural and functional unit of the nervous system

3. Three Parts of the Neuron Dendrite, Cell body, Axon

4. The Parts of the Neuron 1. Dendrites - receive incoming messages to the nerve cell - resemble tree branches 2. Cell Body - contains nucleus

5. Axon -- conducts impulses away from the nerve cell to other neurons - Myelin sheath - fatty material that covers the axon and insulates it which increases conduction speed - Nodes of ranvier -spaces between the myelin sheath where information can become depolarized ( get lost)

6. Terminal Buttons (end bulb) - holds chemicals which communicate with other neurons by firing information across the synapse to the next cell body, organ or muscle

7. Synapse - a very small space in between the end bulb and it’s adjacent cell, organ or muscle

8. a. Transmitters - a chemical messenger between cells/neurons Examples of neurotransmitters- seratonin, GABA, dopamine

9. - excitatory - chemical locks open and neurons are turned on - inhibitory - chemical locks are closed and neurons turn off

10. Seratonin is the brain chemical that is associated with moods, concentration and attention Thinking about the information in the last slides, explain what happens in the brain with people who are depressed

11. b. Receptors - special areas on the dendrite that function like a chemical lock

12. Types of Neurons a.Sensory or Afferent neurons - transmit messages from sensory receptors to the brain and spine

13. a.Inter neurons - located entirely within the brain and spinal cord, intervene between sensory and motor neurons

14. C.Motor or Efferent Neurons - transmit impulses from sensory or inter neurons to muscle cells that contract or gland cells that secrete (sends messages away from the brain) Examples- reflexes

15. Babinski reflex

16. Using information learned in class, explain what happens when you touch a hot stove

17. Somatic Nervous system Controls voluntary activities Such as…

18. Autonomic Nervous system Controls involuntary responses such as heart rate

19. Sympathetic Nervous system Sympathetic - prepares the body for strenuous activity - ex- speeds heart rate

20. Parasympathetic - works to conserve energy in the body and return it to its normal state

21. Somatic Nervous system part of the nervous system that controls voluntary activitiesPart of the Nervopus system that controls voluntary