Chapter 11: The Nervous System

Question 0

nerve

Answer 0

bundle of axons and their sheaths that connects CNS to sensory receptors, muscles, and glands

Question 1

sensory receptors

Answer 1

ends of neurons or separate specialized cells that detect sensations

Question 2

ganglion

Answer 2

collection of neuron cell bodies outside CNS

Question 3

plexus

Answer 3

extensive network of axons and sometimes neuron cell bodies, located outside CNS

Question 4

somatic nervous system

Answer 4

CNS to skeletal muscles
voluntary
single neuron system

Question 5

synapse

Answer 5

junctions of a nerve cell with another cell

Question 6

autonomic nervous system

Answer 6

from CNS to smooth muscle, cardiac muscle, and certain glands
involuntary
two neuron system
sympathetic, parasympathetic, enteric

Question 7

sympathetic

Answer 7

prepares body for physical activity

Question 8

parasympathetic

Answer 8

regulates resting or vegetative functions, such as digesting food or emptying bladdar

Question 9

sensory division of the PNS

Answer 9

afferent: transmits action potentials from receptors to CNS

Question 10

Motor Division of the PNS

Answer 10

efferent: transmits action potentials from CNS to effectors

Question 11

organization of neurons

Answer 11

• cell body: soma
• dendrites: input
• axons: output

Question 12

sensory or afferent neuron

Answer 12

action potential toward CNS

Question 13

motor or efferent neuron

Answer 13

action potential away from CNS

Question 14

interneurons or association neuron

Answer 14

within CNS from one neuron to another

Question 15

Multipolar

Answer 15

motor neurons

Question 16

bipolar

Answer 16

sensory in retina of the eye and nose

Question 17

astrocytes

Answer 17

nourish neurons

Question 18

blood brain barrier

Answer 18

protects neurons from toxic substances, allows exchange of nutrients and wastes products between neurons and blood

Question 19

ependymal cells

Answer 19

form choroid plexuses which secrete cerebrospinal fluid

Question 20

microglia

Answer 20

specialized macrophages that respond to inflammation, phagocytize invaders

Question 21

oligodendrocytes

Answer 21

sheet that forms and protects myelin sheaths that surround axon

Question 22

Schwann cells

Answer 22

neuroglia in the PNS that wrap around axons, form myelin sheath around portion of one axon

Question 23

satellite cells

Answer 23

surround neuron cell bodies in sensory ganglia, provide support and nutrients

Question 24

Node of Ranvier

Answer 24

in myelinated axons, makes impulses faster

Question 25

gray matter

Answer 25

unmyelinated axons, cell bodies, dendrites, neuroglia, integrative functions

Question 26

white matter

Answer 26

myelinated axons. nerve tracts propagate actin potential from one area in the CNS to another

Question 27

difference between presynaptic membrane and post synaptic membrane

Answer 27

presynaptic: cell membrane sending signal
postsynaptic: cell membrane receiving signal

Question 28

leak channels

Answer 28

nongated ion channels are always open, very specific

Question 29

What is the difference between graded potential and action potential?

Answer 29

graded: receptive area (dendrites, cell body), has ligand gated channels, where synapses are
Action: signal conducting area (axon), has voltage gated channels

Question 30

Type A Nerve Fiber

Answer 30

large diameter, myelinated, conduct at 15-120 m/s

Question 31

Type B Nerve fiber

Answer 31

medium diameter, light myelinated, conduct at 3-15 m/s

Question 32

Type C Nerve Fiber

Answer 32

small diameter, unmyelinated, conduct 2 m/s or less

Question 33

Electrical Synapse

Answer 33

gap junctions that allow a local current to flow between adjacent cells, allows neurons to act as one, common in cardiac muscle

Question 34

synaptic vesicles

Answer 34

action potential causes Ca2+ to enter cell that causes neurotransmitter to be released from vesicles