Cells and Nutrition

Question 1

What are the 2 kinds of cells in the human nervous system?

Answer 1

• Neurons: information processers
• Glial cells: supporting cells that provide nutrition and support to neurons

Question 2

What are microglia?

Answer 2

The brain’s “rapid response team”
* Part of the immune system
* Remove waste, viruses, and fungi
* Remove dead/dying/damaged neurons
* Remove prunee ineffective synapse

Question 3

In what diseases are microglia more active?

Answer 3

Alzheimer’s, Autism, MS, Syphilis, HIV, HSV, and depression

Question 4

What are oligodendrocytes?

Answer 4

Octopus-like glial cells that wrap the tips of their “tentacles” around parts of neurons within the CNS to form the myelin sheath–adjusting the axons’ response times
* Each oligodendrocyte can provide myelin for up to 50 axons at the same time

Question 5

Where does white matter get its name?

Answer 5

Oligodendrocytes

Question 6

What are Schwann cells?

Answer 6

(PNS) form a layer of myelin around axons within the PNS
* Small in size but large in numbers in order to myelinate an axon
* Have many different roles, such as astrocyte-like chemical cleanups

Question 7

What do Schwann cells do if damage occurs to a nerve?

Answer 7

Schwann cells arrange themselves in a series of cylinders to guide the nerve’s regrowth
* They can reestablish connection with the muscles and sense organs

Question 8

In the CNS, when a neuron is severed, what happens?

Answer 8

Its new sprouts will encounter scar tissue produced by astrocytes, and they cannot penetrate through them

Question 9

What are radial cells?

Answer 9

Guide the migration of neurons and the growth of their axons and dendrites during embryonic development

Question 10

What is the blood-brain barrier?

Answer 10

A mechanism that surrounds the brain and blocks most chemicals from entering
* Immune system destroys damaged/infected cells throughout the body

Question 11

Why is the blood-brain barrier important?

Answer 11

Neurons in the brain generally do not regenerate, so it is important for viruses, bacteria, and other harmful material from entering

Question 12

What is active transport in the blood-brain barrier?

Answer 12

The protein-mediated process that expends energy to pump chemicals from the blood into the brain (e.g. glucose, hormones, amino acidds, vitamins)

Question 13

What is glucose?

Answer 13

A sugar that is one of the few nutrients that can pass through the blood-brain barrier

Question 14

What do vertebrate neurons depend almost entirely on?

Answer 14

Glucose

Question 15

What do neurons need a steady supply of?

Answer 15

Oxygen

Question 16

What % of all oxygen consumed by the body is used by the brain?

Answer 16

20%

Question 17

What vitamin does the body need to use glucose?

Answer 17

Vitamin B1 (Thiamine)

Question 18

What can be the outcome of prolonged thiamine deficiency?

Answer 18

Death of neurons (Korsakoff’s Syndrome)
* Often the result of chronic alcoholism
* Marked by severe memory impairment

Question 19

How does bacteria influence the brain?

Answer 19

• Stimulate the vagus nerve
• Release chemicals that cross the intestine lining and enter bloodstream
• Stress increases type of bacteria that cause inflammation

Question 20

Regarding the CNS, what does behavior depend on?

Answer 20

Communication between neurons in the CNS