exam 2 nervous system

Question 1

central nervous system

Answer 1

brain and spinal cord

“control center”

Question 2

peripheral nervous system

Answer 2

cranial nerves, spinal nerves, and ganglion

Question 3

define ganglion

Answer 3

group of neuron cell bodies located outside the CNS

Question 4

sensory division

Answer 4

• receives info from body and transmits it to the CNS for processing
• has both CNS and PNS

Question 5

somatic sensory component:

Answer 5

receives sensory info from skin, joints, muscle, special senses

Question 6

visceral sensory component:

Answer 6

receives sensory info from blood vessels and viscera (organs)

Question 7

motor division

Answer 7

transmits info from the CNS to muscles and glands

Question 8

somatic motor component:

Answer 8

innervates skeletal muscle involuntary

Question 9

nervous tissue cells are composed of

Answer 9

neurons and glial cells

Question 10

neurons

Answer 10

respond to stimuli and conduct nerve impulses–primarily amitotic

Question 11

glial cells function

Answer 11

• support and protect neurons

- many more glial cells than neurons, they divide by mitosis

Question 12

cell body

Answer 12

neuron’s control center or “head”

Question 13

chromatophilic substances

Answer 13

rough ER

• function: protein synthesis
• look like darkened “clumps’ within cytoplasm
• not found in axon hillock

Question 14

dendrites

Answer 14

short nerve cell processes

• receive input and send nerve impulses to cell body.
• neuron can have 1 or man dendrites

Question 15

axon

Answer 15

long nerve cell process

-send output

Question 16

axon hillock

Answer 16

cone-shaped portion of cell body from where axon originates

Question 17

what are the glial cells found in the PNS

Answer 17

satellite cells

neurolemmocytes

Question 18

what are the glial cells found in the CNS

Answer 18

astrocytes
oligodendrocytes
microglia
ependymal cells

Question 19

Satellite cells

Answer 19

surround neuron cells in spinal ganglia

-protect cell bodies and regulate nutrient exchange and waste removal

Question 20

neurolemmocyte

Answer 20

• myelinated axons on PNS

- can help regenerate damaged PNS axons

Question 21

What is mylin

Answer 21

• protective covering around axon
• it insulated axon and helps produce faster nerve impulses
• not all axons are myelinated

Question 22

astrocytes

Answer 22

• regulates transfer of materials from blood to the brain (blood brain barrier)
• helps name blood vessels less leaky

Question 23

multipolar neuron

Answer 23

one axon and many dendrites

• most common
• EX: Motor neurons, interneurons

Question 24

bipolar neuron

Answer 24

2 processes– 1 axon and 1 dendrite, limited in location

EX: retina of eye, olfactory neurons in nose

Question 25

unipolar neuron

Answer 25

single process comes off of the cell body and divides into 2 branches - common - EXs: most sensory neurons

Question 26

sensory neuron

Answer 26

brings info to the CNS | -they are either unipolar or bipolar neurons

Question 27

motor (efferent) neurons

Answer 27

takes info from CNS to other parts of the body | -all are multipolar

Question 28

interneuron

Answer 28

helps coordinate and integrates info between sensory and motor neurons - located solely in CNS - "translator" - multipolar

Question 29

in the CNS, myelin sheath is formed by:

Answer 29

oligodendrocytes

Question 30

in the PNS, myelin sheath is formed by:

Answer 30

neurolemmocytes

Question 31

myelination procedure in PNS

Answer 31

1) Neurolemmocytes wrap around a 1mm portion of an axon successfully 2) Cytoplasm and nucleus of neurolemmocyte gets "squeezed" to the outside 3) inner successive layers of the cell membrane make up the myelin sheath

Question 32

neurofibril nodes

Answer 32

- "gaps" between 2 adjacent neurolemmocytes - axon unmyelinated - its at nodes that a nerve impulse is generated

Question 33

myelinated procedure in CNS

Answer 33

similar to process in PNS, but - oligodendrocytes myelinate CNS axons - one oligodendrrocytes myelinated 1mm portions of many axons

Question 34

how does an impulse travel on an unmyelinated axon

Answer 34

spread along entire length

Question 35

how does an impulse travel on a myelinated axon

Answer 35

nerve impulse jumps from node to node