Neurons

Question 1

Universal properties of neurons

Answer 1

excitability, conductivity, secretion

Question 2

Sensory (afferent) neuron function

Answer 2

specialized neurons that detect stimuli and transmit information about them to the Central Nervous System

Question 3

Motor (efferent) neuron function

Answer 3

specialized neurons that send signals predominantly from the Central Nervous System (CNS) to muscle and gland cells, causing them to respond and carry out the body’s actions

Question 4

Interneurons function

Answer 4

neurons that lie entirely within the Central Nervous System (CNS), responsible for processing, integrating, and interpreting information to determine appropriate body responses

Question 5

Soma

Answer 5

control center of a neuron, containing the nucleus and essential cellular components responsible for the neuron’s metabolic functions and protein synthesis; cell body

Question 6

Dendrites

Answer 6

neuron extensions that serve as the primary sites for receiving signals from other neurons

Question 7

Axon

Answer 7

specialized neurite extending from the cell body, designed for rapid signal conduction to remote locations

Question 8

Nucleus

Answer 8

central control center of the neuron

Question 9

Neurofibrils

Answer 9

bundles of actin filaments within the neuron’s cytoskeleton that help compartmentalize the rough endoplasmic reticulum and provide structural support to the neuron

Question 10

Nissl bodies

Answer 10

clusters of rough endoplasmic reticulum in the neuronal cell body, characterized by their dark-staining appearance and critical role in protein synthesis

Question 11

Axon hillock

Answer 11

mound-like region on the neuron where the axon originates from the cell body, and serves as a critical trigger zone for generating action potentials

Question 12

Axolemma

Answer 12

plasma membrane of the axon, responsible for conducting electrical signals and regulating ion movement during neural transmission

Question 13

Axoplasm

Answer 13

internal cytoplasm of the axon

Question 14

Telodendria

Answer 14

terminal branching endings of an axon

Question 15

Axon terminals

Answer 15

bulbous endings of an axon’s terminal arborization that form synapses with other cells

Question 16

4 classes of neurions

Answer 16

anaxonix, bipolar, unipolar, multipolar

Question 17

Anaxonic neuron characteristics and location

Answer 17

• multiple dendrites, no axon
• brain, retina, adrenal medulla

Question 18

Bipolar neuron characteristics and location

Answer 18

• one axon, one dendrite
• found in sensory areas like the nose

Question 19

Multipolar neuron characteristics and location

Answer 19

• one axon, multiple dendrites,
• found in brain and spinal cords

Question 20

Unipolar neuron characteristics and location

Answer 20

• single process leading from cell body
• found in spinal cord sensory pathways

Question 21

Difference between neuronal function and neuroglia function

Answer 21

Neurons: communication
Neuroglia: support, protection, and structural framework

Question 22

Where can cell bodies be found in the CNS and PNS

Answer 22

CNS: gray matter of brain and spinal cord, neuronal tissue, surrounding white matter tracts
PNS: ganglia, nerve clusters, outside the brain and spinal cord

Question 23

Where can axons be found in the CNS and PNS

Answer 23

CNS: white matter of the brain and spinal cord
PNS: cranial and spinal nerves

Question 24

Ependymal cells

Answer 24

specialized glial cells that line the internal cavities of the brain and spinal cord, responsible for producing and circulating cerebrospinal fluid

Question 25

Microglia

Answer 25

small macrophage-like glial cells that act as the brain’s immune defense and maintenance system

Question 26

Astrocytes

Answer 26

most abundant glial cells in the Central Nervous System, characterized by their star-like shape

Question 27

Oligodendrocytes

Answer 27

specialized glial cells that produce myelin sheaths, resembling an octopus with multiple arms that wrap around and insulate axons

Question 28

Satellite cells

Answer 28

peripheral glial cells that surround nerve cell bodies in ganglia, providing insulation and regulating the chemical environment of neurons

Question 29

Schwann cells

Answer 29

peripheral glial cells that surround nerve cell bodies in ganglia, providing insulation and regulating the chemical environment of neurons

Question 30

Cells of the central nervous system

Answer 30

ependymal cells, microglia, astrocytes, oligodendrocytes

Question 31

Cells of the peripheral nervous system

Answer 31

satellite cells, schwann cells

Question 32

How do schwann cells myelinate an axon

Answer 32

• schwann cell spirals repeatedly around a single axon
• lays down up to 100 compact membrane layers
• uses almost no cytoplasm between membrane layers

Question 33

3 types of nerve fibers

Answer 33

large myelinated fibers, small myelinated fibers, small non-myelinated fibers

Question 34

Size, speed, and location differences of the 3 nerve fibers

Answer 34

Large: up to 20 um, CNS and PNS, up to 120 m/s
Small: 2-4 um, CNS and PNS, 3-15 m/s
Non-myelinated: 2-4um, CNS and PNS, 0.5-2 m/s

Question 35

Which nervous system allows for nerve regeneration

Answer 35

peripheral nervous system