Lecture 6 - Nerves Flashcards Preview

Histology > Lecture 6 - Nerves > Flashcards

Flashcards in Lecture 6 - Nerves Deck (56)
Loading flashcards...
1

2 Divisions of the Nervous System

1. Central
2. Peripheral

2

Components of CNS

Brain and Spinal Cord

3

Components of PNS

Cranial, spinal, peripheral nerves and ganglia

4

What are the 2 types of cells in the CNS and PNS?

1. Neurons
2. Glial Cells

5

Features of a Multipolar Neuron (x6)

1. Dendrites (2 or more)
2. Cell Body
3. Axon (one) - goes off into periphery
4. Located in spinal cord
5. Motor Neurons and CNS interneurons
6. Most Neurons

6

Features of Bipolar Neuron (x4)

1. Dendrite (1)
2. Cell Body
3. Axon (1)
4. Sensory neurons of the retina, olfactory mucosa, and inner ear

7

Features of Unipolar Neurons

1. Dendrites
2. Axon - Peripheral Process, Central Process
3. Cell Body w/ Single short process

8

What are the types of neurons based on their functional role?

1. Motor (efferent)
2. Sensory (afferent)
3. Interneuron (more than all other neurons combined)

9

Nissl Bodies

1. Ribosomes
2. RER

10

Are Nissl bodies acidophilic of basophilic?

Basophilic --> lots of ribosomes (acid)

11

Why does the peikaryon have a euchromatic nucleus, very prominent nucleolus, and Nissl bodies?

Making lots of proteins

12

What is the Axon Hillock?

The thicker extension of the axon closest to the cell body

13

What maintains the structure of the neuron?

Neurofilaments (aka intermediate filaments) and neurotubules (aka microtubules)

14

What are the functions of the cytoskeleton in a neuron? (x2)

1. Mechanical Support
2. Intracellular Trafficking

15

Where are neurotransmitters made? Where do they go? How do they get there?

1. NT's are made in the cell body
2. They are stored in synaptic vesicles at the terminal end of the axon.
3. They get there by traveling down the axon using the cytoskeleton (neurofilaments and neurotubules)

16

Is transport in the axon unidirectional or bidirectional?

Bidirectional

17

What are the names for the modes of transportation up and down an axon?

1. Anterograde Transport
2. Retrograde Transport

18

What is the plasma membrane of the axon called?

Axolemma

19

What is the cytoplasm of the axon called?

Axoplasm

20

What does the axoplasm contain?

1. Mitochondria
2. Microtubues
3. Neurofilaments
*Think MMR*
*No protein synth is made here - no ribosomes/rER

21

What are dendrites?

Elongated processes specialized to receive stimuli from other neurons at contact sites known as synapses
*Dendritic Tree

22

Which is longer, dendrite or axon?

Axon

23

Which process will be more numerous, dendrite or axon?

Dendrite

24

What is the dendritic spine?

The site of synaptic contact w/ other neurons

25

What is the purpose of dendrites and the dendritic spines?

Increase surface are to receive as much stim as possible

26

What happens when a neuron receives an impulse?

1. An electrical impulse travels from the dendrite spine to the dendrite
2. Then to the cell body
3. Down the Axon
4. NT is released

27

What does the NT do after it is released?

1. Travels across the synaptic cleft
2. Binds to a receptor on the post synaptic membrane
3. Causes an effect

28

How to best see axons and dendrites on a microscopic image?

Gold Stain
*can also use basophilic stains like hematoxylin*

29

What is in the space between neuronal cell bodies?

1. Glial Cells
2. Glial and Neuronal Process (axons/dendites)

30

What are the major types of glial cells in the CNS?

1. Oligodendrocytes
2. Astrocytes
3. Ependymal Cells
4. Microglia