8.3 Cells Of The Nervous System

Question 1

2 types of cells that make up the nervous system

Answer 1

Neurons

Neuroglia

Question 2

also called nerve cells receive stimuli, conduct action potentials, and transmit signals to other neurons or effector organs

Answer 2

Neurons

Question 3

3 parts to a neuron

Answer 3

cell body

2 types of processes: dendrites and axon

Question 4

contains a single nucleus

Answer 4

cell body

Question 5

source of information for gene expression

Answer 5

nucleus of the neuron

Question 6

surround the nucleus

Answer 6

Extensive rough ER, Golig apparatus, mitochondria

Question 7

organize cytoplasm into ditsinct areas

Answer 7

Large number of neurofilaments (intermediate filaments) and microtubules

Question 8

Short, often highly branching cytoplasmic extensions that are tapered from their bases at the neuron cell body to their tips

Answer 8

Dendrites

Question 9

usually receive information from other neurons or from sensory receptors and transmit the information toward the neuron cell body

Answer 9

Dendrites

Question 10

A single long cell process extending from the neuron cell body

Answer 10

Axon

Question 11

Area where the axon leaves the neuron cell body

Answer 11

Axon hollock

Question 12

conduct action potentials away from the CNS

Answer 12

Axons of sensory neurons

Question 13

conduct action potentials away from the CNS

Answer 13

Axons of motor neurons

Question 14

An axon may remain unbranched or may branch to form ____

Answer 14

collateral axons

Question 15

highly specialized insulating layer of cells surrounding some axons

Answer 15

Myelin sheath

Question 16

have many dendrites and a single axon

Answer 16

Multipolar neurons

Question 17

have two processes: one dendrite and one axon

Answer 17

Bipolar neurons

Question 18

Type of neurons within the CNS and nearly all motor neurons

Answer 18

Multipolar neurons

Question 19

Type of neuron loacted in some sensory organs, such as in the retina of the eye and in the nasal cavity.

Answer 19

Bipolar neurons

Question 20

Have single process extending from the cell body which divides into two processes a short distance from the cell body. One extends to the periphery, the other to the CNS

Answer 20

Pseudo-unipolar neurons

Question 21

Type of neuron in most sensory neurons

Answer 21

Pseudo-unipolar neurons

Question 22

are the nonneuronal cells of the CNS and the PNS

Answer 22

Neuroglia or glial cells

Question 23

Most ____ retain the ability to divide whereas neurons do not

Answer 23

neuroglia

Question 24

serve as majot supporting cells in the CNS

Answer 24

Astrocytes

Question 25

can stimulate or inhibit the signaling activity of nearby neurons

Answer 25

Astrocytes

Question 26

participate with the blood vessel endothelium to form the blood-brain barrier

Answer 26

Astrocytes

Question 27

A permeability barrier between the blood and the CNS

Answer 27

Blood-brain barrier

Question 28

help limit damage to neural tissue

Answer 28

Astrocytes

Question 29

line the fluid-fliled cavities within the CNS

Answer 29

Ependymal cells

Question 30

produce CNS

Answer 30

Ependymal cells

Question 31

help move CSF through the CNS

Answer 31

Ependymal cells

Question 32

act as immune cells of the CNS

Answer 32

Microglia

Question 33

help protect the brain by removing bacteria and cell debris

Answer 33

Microglia

Question 34

provide insulating material that surround the axon in the CNS

Answer 34

Oligodendrocytes

Question 35

provide insulating material that surround the axon in the PNS

Answer 35

Schwann cells

Question 36

rest in indentations of the oligodendrocytes in the CNS and Schwann cells in the PNS

Answer 36

Unmyelinated axons

Question 37

an excellent insulator that prevents almost all ion movement across the cell membrance

Answer 37

Myelin

Question 38

gaps in the myelin sheath that occur about every millimeter between the oligodendrocyte segments or between individual Schwann cells

Answer 38

nodes of Ranvier

Question 39

can occur at the nodes of Ranvier

Answer 39

Ion movement

Question 40

Increases the speed and efficiency of action potential

Answer 40

Myelination of an axon

Question 41

Consists of groups of neuron cell bodies and their dendrites, where there is very little myelin

Answer 41

Gray matter

Question 42

gray matter on the surface of the brain

Answer 42

cortex

Question 43

clusters of gray matter located deeper within the brain

Answer 43

nuclei

Question 44

a cluster of neuron cell bodies

Answer 44

ganglion

Question 45

consists of bundles of parallel axons with their myelin sheaths, which are whitish in color

Answer 45

White matter

Question 46

also called conduction pathways, which propagate action potentials from one area of the CNS to another

Answer 46

nerve tracts

Question 47

bundles of axons and their connective tissue sheaths

Answer 47

nerves