2. Review of Cellular Neuroanatomy

Question 1

Parts of Neuron and Function (3)

Answer 1

1. Cell Body(Soma)-metabolic supply
2. Single Axon-output for electrical impulses
3. Dendrites(including spines)-receive input

Question 2

Gray vs. White Matter

Answer 2

Gray-unmyelinated, primarily somas and dendrites

White-myelinated axons

Question 3

Nissl Stain

Answer 3

Stains “Nissl Substance” made up of basophilic “Nissl Bodies” (rER/ribosomes) in neuronal somas and proximal dendrites

Question 4

Pyramidal Neuron

Answer 4

pear-shaped soma and prominent apical dendrite with a group of basal dendrites

Question 5

Are there organelles at the axon hillock?

Answer 5

NO

Question 6

What is between the axon hillock and the beginning of myelination and why is it important?

Answer 6

Axonal Initial Segment. Site of AP generation

Question 7

Branches of the axon are called?

Answer 7

Collaterals

Question 8

Buzzwords:
Unipolar
Pseudounipolar
Bipolar
Multipolar

Answer 8

Not in humans
Sensory in DRG
Local Circuit Neurons
Motor, pyramidal, purkinje

Question 9

Projection Neuron

Answer 9

integrate info and send axons to other brain areas

• Golgi Type I
• ie. Principal Cells(pyramidal neuron)

Question 10

Interneuron

Answer 10

don’t send axon out of local brain area(local circuit)

• Golgi Type II
• ie. Chandlier, basket and double bouquet cells

Question 11

Electrical vs Chemical Synapse

Answer 11

Electrical-direct connection via gap junctions (6 connexion= 1 connexon; 2 connexons= gap jcn)
Chemical-unidirectional, neurotransmitters released after Ca influx, postsynaptic receptors

Question 12

Name 5 neuronal synapses based on subcellular target

Answer 12

Axosomatic
Axodendritic
     -Axospinous
Axoaxonic
Dendrodendritic

Question 13

Excitatory Neurotransmitters

Answer 13

Glutamate at AMPA and NMDA receptors

Ach at nicotinic

Question 14

Inhibitory Neurotransmitters

Answer 14

Glycine

GABA at GABA-A

Question 15

Modulatory Neurotransmitters

Answer 15

Dopamine
NE
ACh at muscarinic
GABA at GABA-B
Serotonin

Question 16

Excitatory Synapse

Answer 16

Gray’s Type 1
Asymmetric(pronounced postsynaptic density)
Found on Dendrites

Question 17

Inhibitory Synapse

Answer 17

Gray’s Type 2
Symmetric density
Found on Soma

Question 18

How do things move down axon. Anterograde? Retrograde?

Answer 18

Microtubules. Kinesin(antero). Dynein(retro)

Question 19

Supporting Cells and buzzwords (6)

Answer 19

Schwann Cells-myelin PNS; forms 1 internode
Oligodendrocytes-myelin CNS; 1 for 30-50 axons
Astrocytes-Fibrous and Protoplasmic; metabolic
Microglia-Mac of CNS
Satellite Cells-astrocytes in ANS; neural crest
Ependymal Cells-line ventricles; cuboid/columnar

Question 20

Node of Ranvier

Answer 20

Unmyelinated area where APs regenerate

Question 21

Schmidt-Landerman Clefts/Incisures

Answer 21

Small folds of cytosol remaining in the Schwann Cell after wrapping around the axon

Question 22

Endoneurium vs Perieurium

Answer 22

Endo-Thin layer of CT surrounding each nerve fiber

Peri-surrounds the fasicle