Chapter 3: Neurons

Question 1

Neurons

Answer 1

• cells that are specialized for the reception, conduction and transmission of electrochemical signals

Question 2

Cell Membrane

Answer 2

the semipermeable membrane that encloses the neuron

Question 3

Dendrites

Answer 3

the short processes emanating from the cell body, which receive most of the synaptic contacts from other neurons

Question 4

Axon Hillock

Answer 4

the cone shaped region at the junction between the axon and cell body

Question 5

Cell Body

Answer 5

the metabolic center of the neuron, also called the soma

Question 6

Myelin

Answer 6

• the fatty insulation around many axons

Question 7

Nodes of Ranvier

Answer 7

the gaps between sections of myelin

Question 8

Buttons

Answer 8

the button like endings of the axon branches, which release chemicals into synapses

Question 9

Synapses

Answer 9

the gaps between adjacent neurons across which chemical signals are transmitted

Question 10

Multipolar Neuron

Answer 10

a neuron with more than two processes extending from its cell body

Question 11

Unipolar Neuron

Answer 11

a neuron with one process extending from its cell body

Question 12

Bipolar Neuron

Answer 12

a neuron with two processes extending from its cell body

Question 13

Interneurons

Answer 13

neurons with a short axon or no axon, function is to integrate the neural activity within a single brain structure; not to conduct signals from one structure to another

Question 14

Nuclei

Answer 14

clusters of cell bodies in the CNS

Question 15

Tracts

Answer 15

bundles of axons in the PNS

Question 16

Ganglia

Answer 16

clusters of cell bodies in the PNS

Question 17

Nerves

Answer 17

bundles of axons in the PNS

Question 18

Glial Cells

Answer 18

Non-neuron cells found throughout the nervous system

Question 19

Oligodendrocytes

Answer 19

glial cells with extensions that wrap around the axons of some neurons of the CNS
Extensions are rich in myelin

Question 20

Myelin Sheaths

Answer 20

• fatty protector that increase the speed and efficiency of axonal conduction

Question 21

Schwann Cells

Answer 21

second class of glial cells similar to oligodendrocytes within the PNS

Question 22

Microglia

Answer 22

third class of glial cells, smallest size, respond to injury or disease by multiplying, engulfing cellular debris, and triggering inflammatory responses

Question 23

Astrocytes

Answer 23

fourth class of glial cells, largest size, extensions cover the outer surfaces of blood vessels that course through the brain and make contact with neuron cell bodies

Question 24

Neuroanatomical Techniques

Answer 24

techniques used to give a clear view of different aspects of neuronal structure

Question 25

Golgi Stain

Answer 25

use of potassium dichromate and silver nitrate to stain neurons entirely black (shows only silhouettes)

Question 26

Nissl Stain

Answer 26

use of cresyl violet dye to penetrate all cells on a slide binding only to structures in neuron cell bodies

Question 27

Electron Microscopy

Answer 27

coating of neural tissue with electronic absorbing substance, passing bean of electrons through on a photographic film

Question 28

Neuroanatomical Tracing techniques

Answer 28

• injection of dyes into brain then slicing to determine where the dye travelled
  Anterograde (forward)
  Retrograde (Backward)