AP Biology Nervous tissue Nervous System CNS PNS

AP Biology Nervous tissue

Nervous System CNS PNS 12 pairs of cranial Brain Spinal cord nerves 31 pairs of spinal nerves Autonomic nervous system Somatic nervous system [voluntary control] • Sympathetic nerves • Parasympathetic nerves [involuntary control] 2

Central & peripheral nervous system 3

Formation of a typical Spinal nerve 4

Cranial nerves 5

Somatic and autonomic nervous system(overveiw) 6

Nervous Tissue Neurons cells Neuroglial Neurons……………. . ? ? ? • are basic structural and functional units of the nervous system. 7

Neuron 8

Neuron Morphological classification Unipolar / pseudounipolar Bipolar Multipolar Functional classification Sensory neuron Motor neuron Mixed neuron 9

Types of Neuron 10

Sensory and motor neuron 11

Neuroglial cells of PNS CNS 1. Ependymal cells 2. Astrocytes 3. Oligodendrocy 1. Schwann cells 2. Satellite cells tes 4. Microglia 12

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Satellite cells • These are the cells which surrounds the neurons. • It has flat nucleus. • Present only in peripheral nervous system. • Function ü Satellite cells insulate and supports the neuron in the ganglia in PNS ü They also help in metabolic exchange 14

Nerve Structure of neuron • Axoplasm • Axolemma • Myelin sheath 15

Nerve – connective coverings 16

What are……? ? ? Grey matter White matter Nucleus Ganglion 17

Spinal ganglion 18

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Ganglions, Optic nerve & Nerve fiber 20

GANGLIO N • It is an aggregation of nerve cell bodies outside the CNS. • They serve as a relay station to transmit nerve impulses. 1. SPINAL GANGLION (dorsal root ganglion) 2. SYMPATHETIC GANGLION (Autonomic) 21

Dorsal root ganglion 22

Dorsal root ganglion 23

Spinal Ganglion 24

Dorsal root ganglion (MICROSCOPE) 25

Sympathetic ganglion 26

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Sympathetic ganglion 28

Sympathetic ganglion 29

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Optic nerve 31

Optic nerve 32

Optic nerve 33

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Difference between spinal and sympathetic ganglion FEATURES SPINAL ganglion SYMPATHETIC ganglion 1. Neurons Pseudounipolar Multipolar 2. Cell bodies Large & rounded with afferent neurons Small & irregular with efferent neurons 3. Nucleus Central with prominent nucleolus Eccentric with prominent nucleolus 4. Satellite cells Numerous Few 5. Neurons & nerve fibers Nerve fibers are in bundle and cell bodies are also groups Nerve fibers and cell bodies are Scattered 35

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