lecture 16

Question 1

what are the two general classes of cell in the CNS and PNS

Answer 1

neurons and Glia

Question 2

what makes the PNS

Answer 2

peripheral nerves and ganglia

Question 3

role of neurons

Answer 3

cells specialised for transmission of information

Question 4

role of glia

Answer 4

support for neurons

Question 5

in the CNS, but not cerebrum or spinal cord, what is a group of cell bodies

Answer 5

Nucleus (pl. = Nuclei)

Question 6

what is a group of axons in the CNS, excluidng the cerebrum and spinal cord

Answer 6

a tract

Question 7

Group of cell bodies in
cerebral cortex or spinal cord

Answer 7

grey matter

Question 8

• Bundle of axons in
  cerebral cortex or spinal cord

Answer 8

white matter

Question 9

whats a group of cell bodies in the PNS

Answer 9

a ganglion

Question 10

what is a group of axons in the PNS

Answer 10

a nerve

Question 11

what is the summation zone on the neuron

Answer 11

the axon hillock

Question 12

describe a multipolar axon

Answer 12

many processes extend from the cell body

Question 13

describe a unipolar axon

Answer 13

one process extends out of the cell body, this one process branches out into the dendrite and axon.

Question 14

describe a bipolar axon

Answer 14

two processes extending out of the cell body, one is concerned with information input, the other output

Question 15

describe an anaxonic axon

Answer 15

No distinct axon
* All processes look alike

Question 16

what are the four CNS Glia types

Answer 16

oligodendrocytes, ependymal cells, microglia and Astrocytes.

Question 17

what are the three features of the astrocytes

Answer 17

injury response, Supply nutrients to neurons
* Ensheath blood capillaries

Question 18

what are the two features of microglia

Answer 18

Immune cells of the CNS
* Engulf microorganisms and
debris

Question 19

what are the 2 features of ependymal cells

Answer 19

line the fluid-filled spaces in the CNS and spinal cord, the ventricles
Have cilia (hair-like processes) to circulate CSF

Question 20

what are the 2 features of oligodendrocytes

Answer 20

Support nerve fibres
* Ensheath them with myelin

Question 21

in the PNS what makes the myelin sheath

Answer 21

the Schwann cells

Question 22

what are the two features of the schwann cells

Answer 22

Support peripheral nerve fibres
* Ensheath them with myelin

Question 23

what cells are the schwann cells similar to

Answer 23

• Similar to oligodendrocytes (CNS)

Question 24

what is the myelin sheath made of and what does it do

Answer 24

its made of lipids, as they wrap their plasma membrane around the axon, and it serves to increase the speed at which an action potential is propogated