Lecture 17

Question 1

What are the two types of information transmitted in the body? What are the differences?

Answer 1

Somatic = voluntary, things we have awareness and control over
Autonomic = involuntary, things that we do not have awareness and control over

Question 2

For somatic efferent transmission, what are the neurons involved? What are their structure?

Answer 2

Upper motor neuron :
- cell body in brain, axon in spinal cord
Lower motor neuron :
- Cell body in spinal cord, axon in spinal nerve

Both are myelinated.

Question 3

What is the neurotransmitter in somatic efferent transmission?

Answer 3

Acetylcholine (ACh)

Question 4

What type of junction is formed between lower motor neuron and an effector?

Answer 4

Neuro-muscular junction

Question 5

For autonomic efferent transmission, what are the neurons involved? What are their structure?

Answer 5

Neuron 1:
- cell body in brain, axon in brain or spinal cord
Neuron 2:
- cell body in brain or spinal cord, axon in PNS
Neuron 3:
- cell body and axon in PNS
- unmyelinated

Question 6

Where is the synapse for neuron 2 in autonomic efferent transmission?

Answer 6

Autonomic ganglion

Question 7

Where is the synapse for neuron 3 in autonomic efferent transmission?

Answer 7

Effector

Question 8

What neurotransmitters do neuron 2 and 3 in autonomic efferent transmission produce?

Answer 8

Neuron 2 = Acetylcholine
Neuron 3 = Mostly norepinephrine, but some acetylcholine

Question 9

What is the difference between sympathetic and parasympathetic responses?

Answer 9

Sympathetic :
- fight or flight
- acute stress respose
Parasympathetic :
- rest and digest
- prepares body for restful situations

Question 10

What are the structural differences between neurons 2 and 3 in sympathetic vs parasympathetic nervous systems?

Answer 10

Sympathetic :
- short axon
- close to CNS
- long axon
Parasympathetic :
- long axon
- distant from CNS
- short axon

Question 11

In the sympathetic nervous system, where is the cell body, axon terminal and synapse of the preganglionic neuron? What is the length of the axon?

Answer 11

Cell body = thoracolumbar levels of spinal cord
Axon terminals + synapse = sympathetic ganglion
Axon = short

Question 12

What is the length of the axon in the post-ganglionic neuron?

Answer 12

Long

Question 13

What are the sympathetic chain ganglia?

Answer 13

• on either side of vertebral column
• 21-23 pairs
• place where neuron 2 synapses onto neuron 3 input zone

Question 14

In the parasympathetic nervous system, where is the cell body, axon terminal and synapse of the preganglionic neuron? What is the length of the axon?

Answer 14

Cell body = cranial (brainstem) + sacral (spinal cord) levels
Axon terminal + synapse = parasympathetic ganglia

Axon is long.

Question 15

In the parasympathetic nervous system, where is the cell body of the postganglionic neuron? What is the length of the axon?

Answer 15

Cell body is in parasympathetic ganglia. Axon is short.