Chap 14

Question 1

Nervous system

Answer 1

all nervous tissue in the body

Question 2

central nervous system

Answer 2

brain and spinal cord

Question 3

peripheral nervous system

Answer 3

cranial nerves, spinal nerves, and ganglia

Question 4

Functionally divided:

Answer 4

sensory and motor nervous systems

Question 5

sensory nervous system

Answer 5

conveys sensory information to the CNS

Question 6

motor nervous system

Answer 6

conducts motor commands to the muscles and glands

Question 7

neuron characteristics

Answer 7

excitable
transmit nerve impulses
non mitotic

Question 8

glial cells

Answer 8

completley surround and support neurons

Question 9

generally neurons have:

Answer 9

a cell body, dendrites and an axon

Question 10

classified structurally as

Answer 10

unipolar, bipolar, or multipolar depending on the number of attachments to the cell body.

Question 11

classified functionally as

Answer 11

sensory, motor or interneurons

Question 12

CNS glial cells:

Answer 12

astrocytes, ependymal cells, microglial cells, and oligodendrocytes

Question 13

astrocytes

Answer 13

help form the blood brain barrier and regulate tissue fluid composition

Question 14

ependymal cells

Answer 14

line CNS cavities and produce cerebrospinal fluid

Question 15

microglial cells

Answer 15

act as phagocytes in nervous tissue

Question 16

oligodendrocytes

Answer 16

mylinate CNS axons

Question 17

PNS glial cells

Answer 17

satellite cells and nerolemmocytes

Question 18

satellite cells

Answer 18

support neurons cell bodies in ganglia

Question 19

nerolemmocytes

Answer 19

mylinate PNS axons

Question 20

Nerve impulse:

Answer 20

a rapid movement of a charge along a neurons plasma membrane

Question 21

Mylination

Answer 21

oligodendrocytes (CNS) and nerolemmocytes (PNS) form a discontinuous mylin sheath along the axon, with small gaps (neurofibril nodes)

Question 22

neurofibril nodes

Answer 22

small gaps between mylin sheath help conduct impulses faster

Question 23

unmylinated axons

Answer 23

associated with a neurolemmocyte but not ensheathed by it.

Question 24

Wallerian degeneration

Answer 24

regeneration of damaged neurons

limited to PNS axons that are able to regrow under certain conditions

Question 25

Epineurium

Answer 25

surrouds fascicles

Question 26

perineurium

Answer 26

surrounds individual fasicles

Question 27

endoneurium

Answer 27

surrounds individual axons

Question 28

synapse

Answer 28

a specialized junction between two excitable cells where a nerve impulse is transmitted

Question 29

synaptic knobs

Answer 29

swellings of axons at their end branches

Question 30

synaptic cleft

Answer 30

space between the presynaptic and postsynaptic cells

Question 31

classification of synapses

Answer 31

axodendritic, axosomatic or axoaxonic

Question 32

axodendritic

Answer 32

most common: presynaptic knobs synapse with postsynaptic dendrites (standard delivery)

Question 33

axosomatic

Answer 33

between synaptic knobs and the cell body of postsynaptic neuron (express delivery)

Question 34

axoaxonic

Answer 34

``` least common: presynaptic knob with postsynaptic knob (first class delivery) *usually overides brains orders ```

Question 35

electrical synapses

Answer 35

a flow of ions pass from presynaptic cell to postsynaptic cell through gap junctions

Question 36

chemical synapses

Answer 36

nerve impulse causes a release of a chemical neurotransmitter from presynaptic cell that induces response in the postsynaptic cell.

Question 37

what increases rate of conduction?

Answer 37

presence of a myelin sheath, larger the axon diameter.

Question 38

neuronal pools

Answer 38

groups of interneurons- cordinate and integrate nervous activity.

Question 39

converging circuit

Answer 39

neurons synapse at a single postsynaptic neuron | >----

Question 40

diverging circuit

Answer 40

spreads information to several neurons | -----<

Question 41

reverberating circuit

Answer 41

neurons continue to restimulate presynaptic neurons in the circuit. -0

Question 42

Parallel after discharge circuit

Answer 42

involves parallel pathways that process the same information over different amounts of time and deliver that information to the same output cell. l l l \ l / V