Neurons and Glia

Question 1

What two things are composed of neurons and glia?

Answer 1

The brain and the spinal chord

Question 2

What is the function of neurons?

Answer 2

Processing information and conducting electrical impusles

Question 3

What is function of glia?

Answer 3

Mechanical and metabolic support

Question 4

What 3 things makes up the neuron?

Answer 4

1. Dendrites
2. Cell body (soma)
3. Axon

Question 5

What are dendrites?

Answer 5

Recieve information from other neurons (the input part of the neuron)

Question 6

What is the axon?

Answer 6

Conveys information to other nerve cells (the output part of the neuron)

Question 7

How many axons do neurons normally have?

Answer 7

Just one that emerges from the cell body

Question 8

What are the dendrites and axons sometimes collectively known?

Answer 8

Neurites

Question 9

What two things make up the cell body?

Answer 9

The nucleus and the cytoplasm (perikaryon)

Question 10

What is different between the nucleus in a neuron as compared to another cell?

Answer 10

Adult neurons do not replicate and the DNA is only involved in protein synthesis (it a blueprint for construction of neuronal components)

Question 11

What manufactures the ribosomes of the neurons?

Answer 11

The nucleolus

Question 12

The combination of ER and ribosomes is called the rough ER; what else can they be called?

Answer 12

Nissl bodies (seen by nissl staining)

Question 13

Where are microtubules found in the neruon and what are they responsible for?

Answer 13

The dendrites, cell body and axon and are responsible for transporting packaged proteins

Question 14

What else are the microtubules involved in that provides support for the neruon?

Answer 14

The form the cytoskeleton

Question 15

What are lipofucin bodies in neurons?

Answer 15

The scrap yard of the neuron which contains the waste products of the old cells

Question 16

What cellular components have a similar function in neurons as they do in normal cells?

Answer 16

Ribosomes, the golgi apparatus, mitochondria and lysosomes

Question 17

What do the dendrites mainly contain in terms of cellular components?

Answer 17

Mitochondria and free ribosomes

Question 18

What the connections with other neurons formed in the dendrites known as?

Answer 18

Synapses

Question 19

What specialised structures of the dendrites and the synapses usually made on?

Answer 19

Spines

Question 20

What are the four parts of the axon?

Answer 20

1. The axon hillock
2. The axon proper
3. Axon collaterals
4. The axon terminals

Question 21

What the axon hillock?

Answer 21

The part of the axon that emerges from the cell body and contains lots of voltage gated ion channels to generate action potentials

Question 22

What is the axon proper?

Answer 22

The main part of the axon

Question 23

What is the axon collaterals?

Answer 23

The branches of the axon that go off to numerous locations

Question 24

What is the axon terminals?

Answer 24

Swellings (boutons) that form synpases

Question 25

Why is important that axons have a transport for proteins?

Answer 25

Because they dont contain ribosomes to make their own proteins

Question 26

How does transport to the axon occur and what is this known as?

Answer 26

Along microtubules in axoplasmic transport

Question 27

How fast is axoplasmic transport?

Answer 27

Very fast - 1000mm/day

Question 28

What is axoplasmic transport towards the cell body called?

Answer 28

Retrograde transport

Question 29

What is axoplasmic transport away from the cell body called?

Answer 29

Anterograde transport

Question 30

Why would retrograde transport be useful?

Answer 30

To get rid of waste products back to the soma for them to be broken down

Question 31

What are the 5 ways to classify neurons?

Answer 31

1. Number of neurites 2. Shape 3. Connections 4. Axons 5. Neurotransmitters

Question 32

What are the three types of neurons classified under number of neurites?

Answer 32

Unipolar, bipolar and multipolar

Question 33

What is an example of a unipolar neuron?

Answer 33

Sensory neurons

Question 34

What is an example of a bipolar neuron?

Answer 34

That ones connecting the rods and cones in the eyes to the brain

Question 35

What kind of shapes can neurons have?

Answer 35

Pyramidal, stellate

Question 36

What 3 types of neurons are there in the classification based on connections?

Answer 36

1. Primary sensory neurons 2. Motoneurons 3. Interneurons

Question 37

What are primary sensory neurons?

Answer 37

Neurons that form connection with sensory surfaces (skin, retina etc)

Question 38

What are the motoneurons?

Answer 38

Neurons that form connections with muscles

Question 39

What are interneurons?

Answer 39

Neurons that form connections with other neurons

Question 40

What are the two types of neurons classified under axons?

Answer 40

1. Golgi type 1 (long axons) | 2. Golgi type 2 (local axons)

Question 41

What are examples of three neurons classified under neurotransmitters?

Answer 41

1. Cholinergic neurons (release acetylcholine) 2. Glutamergic neurons (glutamide) 3. Peptitergic neurons (peptides)

Question 42

How much of the brain is composed of glia?

Answer 42

90%

Question 43

What are the three classes of glia?

Answer 43

1. Astrocytes 2. Oligodendrocytes 3. Microglia

Question 44

What are astrocytes and oligodendrocytes sometimes collectively known?

Answer 44

Macroglia

Question 45

What is the most numerous type of glial cells?

Answer 45

Astrocytes

Question 46

Name two functions of the astrocytes:

Answer 46

1. Repair in damaged neurons | 2. Regulate flow of ions and molecules in the extracellular fluid

Question 47

How many organelles do astrocytes contain?

Answer 47

Very few

Question 48

How many organelles do oligodendrocytes contain?

Answer 48

Lots

Question 49

What is the main function of oligodendrocytes?

Answer 49

They make myelin that forms a sheath around the axons of neurons?

Question 50

What is myelin composed of?

Answer 50

Lipids

Question 51

The myelin sheath around the axon is not continuous; what are the gaps in it called?

Answer 51

The nodes of ranvier

Question 52

What do the Node of Ranvier do?

Answer 52

Increase the speed of electrical conduction of the axon

Question 53

In what part of the nervous system do oligodendrocytes make myelin?

Answer 53

The central nervous system

Question 54

What makes myelin in the peripheral nervous system?

Answer 54

Schwann Cells

Question 55

What are microglia?

Answer 55

Phagocytes that remove waste

Question 56

How many neurons in the CNS nie every day that need to be removed by microglia?

Answer 56

100,000