Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Histology Exam 2 > Nervous Tissue > Flashcards

Nervous Tissue Flashcards

0
Q

What is the CNS?

A

Central nervous system consisting of brain and spinal cord. Integrative and control centers of body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

Two cell types and functions of nervous tissue

A

Neurons - receptive, integrative, and motor function
Neuroglial cells - Support and protection of neurons
Derived from ectoderm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is PNS?

A

Peripheral nervous system consisting of cranial nerves and spinal nerves. Communication lines between the CNS and the rest of the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are afferent neurons?

A

Sensory nerves, somatic and visceral fibers that conduct impulses from receptors to the CNS.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are efferent neurons?

A

Motor nerve fibers that conduct impulses from the CNS to the effectors (muscles and glands)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Efferent neurons are subdivided into? What do they do?

A

Somatic - voluntary, conducts impulses from the CNS to skeletal
Autonomic - Visceral motor, conducts impulses from the CNS to cardiac muscles, smooth muscles, and glands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Autonomic nervous system is subdivided to? Functions?

A

Sympathetic - mobilizes body systems during activity

Parasympathetic - Conserves energy, promotes house-keeping functions during rest

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

T or F: There are cell bodies in the PNS

A

F, only in the CNS or peripheral ganglia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe the general structure of a neuron

A

Cell body (perikaryon, soma), dendrites (receptive region), nucleus, nucleolus (enlarged), Nissl bodies, axon (axon hillock)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are nodes of Ranvier?

A

Spacing between neurilemma (myelin) and Schwann cell where saltatory signals are propagated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are Nissl bodies?

A

Aggregates of rough ER that stain dark purple in H&E

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

T or F: Golgi is found in dendrites

A

F (only organelle not found in neuron extensions)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is a bipolar neuron?

A

One axon and one dendrite extension in line with cell body. Very rare, found in olfactory and retina.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is a unipolar neuron?

A

Two axons that extend from a common channel off the cell body. Sensor cell type found in dorsal root ganglia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is a multipolar neuron?

A

Most common. Motor neuron with dendrites off of cell body and a single axon.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Where are pyramidal neurons found?

A

Hippocampus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Function of sensory/afferent neurons?

A

Receive stimulus from internal and external environment and conduct to CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Function of motor/efferent neurons

A

Conduct impulses from CNS to other neurons, muscles, glands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the function of interneurons?

A

Connect other neurons in chain or sequence. Important in regulating activity within a network

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What three types of cytoskeleton are found in neurons?

A

Actin microfilaments - 6 nm diameter associated with plasma membrane, structural support
Neurofilaments - 10 nm diameter intermediate filaments in cytoplasm for structural support
Microtubules - 24 nm diameter found in cytoplasm, structural support and transport

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Describe axon transport

A

Anterograde transport to plus end of axon (kinesin active, dynein inactive)
Retrograde transport to negative end of axon (dynein active, kinesin inactive)

21
Q

Where is the MTOC for neurons located?

A

Cell body (negative end of microtubule)

22
Q

What is fast axonal transport?

A

20-40 cm/day, antero and retrograde, membrane bound vesicles and mitochondria

23
Q

What is slow axonal transport?

A

~1 mm per day, anterograde only!, cytoskeleton components and other soluble proteins

24
Q

What are synapses?

A

Sites of impulse transmission between pre and post synaptic cells

25
Q

Two types of synapses?

A

Electric and Chemical

26
Q

Define electrical synapses. Common?

A

Use gap junctions. Not common in mammals

27
Q

Describe chemical synapse structure

A

Axon terminal bouton where NT is packaged and released, post-synaptic apparatus containing receptors for NT, synaptic cleft is the gap between the pre and post synaptic membranes which the NT diffuses through

28
Q

Describe the function of the neuromuscular junction (motor endplate)??

A

Nerve stimulate release of NT into the cleft (ACh for example) stimulating change in the sarcolemma down the T tubules for fiber contraction. Enzymes in the cleft break down ACh to limit the twitch.

29
Q

What is myasthenia gravis?

A

Autoimmune disease against ACh receptor leading to muscle weakness (seen in eyelids first!)

30
Q

What is botulism?

A

Toxin from clostridium botulinum which blocks NT release most notably at the Neuromuscular junction

31
Q

Neurotoxins are common in what?

A

Snake, spider, insect venoms

32
Q

Function of oligodendrocyte

A

CNS myelin production and electrical insulation

33
Q

Function of microglial cells

A

CNS macrophage activity (part of MPS)

34
Q

Function of astrocyte

A

CNS structural support, BBB, ion homeostasis, NT uptake, growth factors

35
Q

Function of nervous satellite cell

A

Peripheral ganglia, structural support, growth factors

36
Q

Function of Schwann cells

A

Peripheral nerves, myelin production, electrical insulation

37
Q

T or F: Peripheral nerves can be made up of both sensory and motor neurons

A

T (dont typically specify until close to site of innervation)

38
Q

Describe packaging of a peripheral nerve

A

Axon surrounded by endoneurium, bundled into fasicles by perineurium, then bundles are bundled b epineurium

39
Q

Myelin formers in CNS? In PNS?

A

Oligodendrocytes. Schwann cells.

40
Q

Describe myelination in PNS

A

Can be done by Schwann cell which envelops the axon and rotates around in successive layers. Cytoplasm is forced out between membranes to form the sheath

41
Q

Describe unmyelinated axon in PNS

A

Schwann cell wraps around multiple axons in a bundle.

42
Q

Perineurial epitheloid cells are used to?

A

Establish BBB via tight junctions

43
Q

T or F: Oligodendrocytes myelinate multiple axons at many points

A

T

44
Q

What is a node of ranvier?

A

Space between Schwann cells where action potentials are propagated in saltatory transmission

45
Q

Loss of myelin leads to?

A

Lesser ability to conduct signal. Disorientation and muscle weakness

46
Q

Describe hereditary motor and sensory neuropathy Type I

A

Mutation in PMP-22 causes demyelination of PNS though loss of PMP-22 activity

47
Q

What is Charcot-Marie-Tooth syndrome Type I

A

Duplication of PMP-22 results in Schwann cell hyperplasia in PNS. Leads to constriction of nerves and loss of function

48
Q

What is Wallerian degeneration?

A

Damaged axon degrades down to last node before cell body. Cell body bloats and loss of Nissl bodies.

49
Q

T or F: PNS can regenerate

A

T

50
Q

PNS regeneration comes with what caveat?

A

Repair tends to not be as good as original, usually introduces more nodes leading to slower and weaker signals

Histology Exam 2 (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions