Classification of Neurons (Quiz 2)

Question 1

Classification of neurons is based on function. There are 3 neuronal types. What are they?

Answer 1

1) motor
2) sensory
3) interneuron

note: most neurons are interneurons

Question 2

Based on the number of processes, there are 4 neuronal types. What are they?

Answer 2

1) unipolar
2) bipolar
3) pseudounipolar
4) multipolar

note: all of these have to have a soma and axon!

also, multipolar neurons are the most common

Question 3

The cylindrical process called an _________ conducts info away from the cell body

Answer 3

axon

Question 4

The axon gives rise to a series of terminal extensions called ____________ that form synapses on other neurons

Answer 4

teledondria

Question 5

Neuronal signaling is _______________

Answer 5

unidirectional (AP can only go in 1 direction)

Question 6

T/F: neurons are both electrically and chemically excitable

Answer 6

true!

electrically through voltage gated channels

chemically through neurotransmitters

Question 7

What is a multipolar neuron?

Answer 7

has many dendrites/branching from the cell body

Question 8

What is a bipolar neuron?

Answer 8

-soma is in the center of 2 processes
-1 axon heading to the axon terminal, and the other process is all the dendrites uniting into 1 long process
-the teledondria have multiple synapses

Question 9

What is a pseudounipolar neuron?

Answer 9

-dendrites unite into 1 process then the axon starts
-soma is off to the side

Question 10

What is a unipolar neuron?

Answer 10

-only 1 process is seen
-soma is on one end
-dendrites unite in middle and then lead into an axon

Question 11

What is an apolar neuron?

Answer 11

-an anaxonic neuron
-it appears to not have an axon but it does

Question 12

The only grey matter in the PNS is called….

Answer 12

ganglia (its where a bunch of cell bodies are siting next to each other from pseudo-unipolar neurons)

Question 13

When do unipolar neurons form?

Answer 13

during development but are rare in the adult brain

Question 14

Unipolar neurons are typically _________ neurons with receptors located within the skin, joints, muscles, and internal organs

Answer 14

sensory

Question 15

Where are the cell bodies found of unipolar neurons?

Answer 15

in spinal and cranial nerve ganglia

Question 16

Bipolar neurons are in the ________, olfactory epithelium, and ganglia of the vestibulocochlear nerve (CN VIII)

test q

Answer 16

retina (involved in vision)

Question 17

Which neurons are only known to be sensory neurons and are involved in the transmission of senses like smell, taste, sight, hearing, touch, balance, and proprioception?

Answer 17

bipolar neurons

Question 18

The vast majority of vertebrate neurons are _________

Answer 18

multipolar

Question 19

Which neuron class based on processes is this?
-motor neurons and interneurons
-pyramidal neurons in the cererbral cortex
-purkinje cells of the cerebellar cortex

test q

Answer 19

multipolar neurons

Question 20

Multipolar neurons form 2 groups according to the length of their axon. What are the 2 groups?

Answer 20

1) long-axon multipolar neuron (Golgi type I)
2) short- axon multipolar neurons (Golgi type II)

Question 21

Which type of multipolar neuron is this?
-have axons that pass from their neuronal cell body and extend for a considerable distance before ending
-form commissures, association, and projection fibers of the CNS
-also known as projection neurons (note: both multipolar and interneurons can be projection neurons- its a broad term)
-these neurons form peripheral nerves and tracts of the CNS

Answer 21

long axon multipolar (golgi type I) neurons

Question 22

Which type of multipolar neuron is this?
-short axons that remain near the cell body of origin
-have a star like appearance
-they do not send branches out of the gray matter
-numerous in the cerebral cortex, cerebellar cortex, and retina
-works functionally as an interneuron

Answer 22

short axon multipolar (golgi type II) neuron

Question 23

The major technique available for studying the shapes and sizes of neurons was _____________, a method that infiltrates all the processes of a small percentage of neurons with heavy metals and it reveals little about the function of an individual cell. Micropipette electrodes can be used as mini needles to inject tracers, dyes, markers, and antibodies.

Answer 23

golgi staining

Question 24

What is immunocytochemistry?

Answer 24

-its genetic tags and genetic manipulation to express fluorescent markers
-used to identify neurotransmitters and enzymes

Question 25

The _______ stain reveals the _________ of the arborizations of cortical neurons by completely staining a small percentage of them

test q

Answer 25

Golgi, shapes

Question 26

The ________ method stains the ____________ of all neurons, showing their shapes and packing densities

test q

Answer 26

Nissl, cell bodies

Question 27

The Weigert method stains _________, revealing the horizontally oriented bands of Baillarger and the vertically oriented collections of cortical afferents and efferents

Answer 27

myelin