1. Nervous System

2. Functions of Nervous System The nervous system is the major controlling, regulatory, and communicating system in the body. It is the center of all mental activity including thought, learning, and memory. Together with the endocrine system, the nervous system is responsible for regulating and maintaining homeostasis. Through its receptors, the nervous system keeps us in touch with our environment, both external and internal.

4. Central Nervous System (CNS) Includes Brain and Spinal Cord Responsible for integrating motor and sensory information Seat of intelligence memory and emotion

5. Peripheral Nervous System (PNS) Includes all nerve tissue outside the CNS – Afferent division – brings sensory information TO CNS – Efferent division – sends commands FROM CNS to muscles and glands

6. Somatic Nervous System (SNS) Part of the efferent system of the PNS Voluntary control over skeletal muscles A.Central nervous system B. Peripheral nervous system B1. Somatic nervous system B2. Autonomic nervous system Diagram :

7. Autonomic nervous system (ANS) Part of the PNS Automatic regulation of smooth muscle, cardiac muscle and gland activity or secretions

8. Cellular Organization in Neural Tissue

9. Neuron with synapse

10. Classes of Neurons

11. Neuron transmissionNeuron transmission – sending & receivingsending

12. Cellular Organization in Neural Tissue Neuroglia – Regulate environment around neuron – Provide support for neural tissue – Act as phagocytes – Aka glial cells – More numerous than neurons

13. Neuroglia, aka glial cells

14. Diagram pg 201 (black book) Interaction of neurons and glial cells

15. Neuroglia- Astrocytes Most numerous Maintain the blood brain barrier Repair damaged neural tissue

16. Neuroglia- oligodendrocytes Create myelin Improves the speed of impulse conduction on an axon

17. Neuroglia- microglia Smallest and rarest Phagocytic white blood cells Protect neurons

18. Neuroglia- ependyma Produce cerebral spinal fluid (CSF)

19. Neuroglia- Schwann cells Most important glial cells Also create myelin

20. Neurotransmitters Chemical that send messages from neuron to neuron or from neuron to other tissues – Ach – stimulates muscle contraction – Norepinephrine – creates an excited state in the organism – Dopamine and serotonin – effects are inhibitory

21. Dopamine and Cocaine Cocaine is a mood- altering drug that interferes with normal transport of the neurotransmitter dopamine, which carries messages from neuron to neuron. When cocaine molecules block dopamine receptors, too much dopamine remains active in the synaptic gaps between neurons, creating feelings of excitement and euphoria.

23. Blood Brain Barrier Maintained by astrocytes Cause capillaries of CNS to become impermeable to many compounds Example: some antibiotics can not help heal brain infections because they can’t cross the barrier

24. Great Animations to helpAnimations An Unbelievable Brain!!!