Mod6-Obj1: Organisation of autonomic vs. somatic nervous system

Question 1

Somatic vs. autonomic

-Similarities

Answer 1

Both are efferent divisions that distribute motor commands

Question 2

Somatic vs. autonomic

-Differences

Answer 2

• Neural pathways (efferent)
• Effectors
• Organ response
• Neurotransmitters

Question 3

Somatic nervous system

Answer 3

Conducts motor impulses from motor cortex to skeletal muscles

Question 4

Somatic output controls…

Answer 4

• Voluntary movement

- Involuntary movement (somatic reflexes)

Question 5

Somatic motor pathway

Answer 5

Effectors innervated by lower motor neuron (LMN) that exits CNS:

1. ) Via a spinal nerve
2. ) Via a cranial nerve

Question 6

Somatic motor pathway: via a spinal nerve

Answer 6

LMN cell body located in a motor nuclei of anterior grey horn
-Axon exits spinal cord via ventral root of a spinal nerve

Question 7

Somatic motor pathway: via a cranial nerve

Answer 7

Cell body in a brainstem nucleus

Question 8

Autonomic nervous system

Answer 8

Conducts motor impulses from the hypothalamus to cardiac and smooth muscle, glands

Question 9

Autonomic output controls…

Answer 9

involuntary activities

• Visceral organ function
• Glandular activity

Question 10

ANS: Motor pathways

Answer 10

• CNS interneuron
• Preganglionic neuron (connect to postganglionic)
• Postganglionic neuron (affect visceral glands)

Question 11

ANS: Motor pathways

Answer 11

• CNS interneuron
• Preganglionic neuron (connect to postganglionic)
• Postganglionic neuron (affect visceral glands)

Question 12

Autonomic nervous system controls organ function to support…

Answer 12

Homeostasis

Question 13

ANS: Hypothalamus

Answer 13

Contains integrative centres (nuclei) that control autonomic activity

Question 14

Hypothalamus is responsive to which other areas of the brain?

Answer 14

• Cerebral cortex

- Limbic system

Question 15

Hypothalamus mediates ANS activity via nuclei in what area of the brain?

Answer 15

Brainstem i.e.) Medulla obongata

Question 16

Hypothalamus mediates ANS activity via nuclei in what area of the brain?

Answer 16

Brainstem i.e.) Medulla obongata

Question 17

ANS motor pathways: effectors innervated by 2 neuron chain

Answer 17

1. ) Preganglionic neuron

2. ) Postganglionic neuron

Question 18

ANS motor pathways: effectors innervated by 2 neuron chain

Answer 18

1. ) Preganglionic neuron

2. ) Postganglionic neuron

Question 19

Autonomic motor pathways: Preganglionic neuron

Answer 19

Cell body in CNS

-Axon exits CNS and synapses with postganglionic neuron in a ganglion

Question 20

Autonomic motor pathways: Postganglionic neuron

Answer 20

Cell body in ganglion (near CNS or effector)

-Axon exits ganglion to innervate effector

Question 21

Neurotransmitters: Somatic nervous system

Answer 21

Acetylcholine (ACh)

-Always excitatory (muscle contraction)

Question 22

Neurotransmitters: ANS

Answer 22

Preganglionic
-ACh (always excitatory)
Postganglionic
-Parasympathetic=ACh 
-Sympathetic=NA (Noradrenaline, excitatory or inhibitory)

Question 23

Neurotransmitters: ANS

Answer 23

Preganglionic
-ACh (always excitatory)
Postganglionic
-Parasympathetic=ACh 
-Sympathetic=NA (Noradrenaline, excitatory or inhibitory)

Question 24

Somatic nervous system summary

-Voluntary control

Answer 24

Innervates skeletal muscle
-One peripheral LMN:
+Neuron cell body in CNS (motor neuron of anterior gray horn of brain stem)
+Axon extends (spinal or cranial nerves) to skeletal muscle
-Always stimulates skeletal muscle
-Controls movement

Question 25

Autonomic nervous system summary

-Involuntary control

Answer 25

Innervates cardiac & smooth muscles, glands
-Two peripheral motor neurons:
+Preganglionic neuron cell body in CNS (motor neuron of lateral gray horn or brain stem) whereby the axon synapses with postganglionic neuron cell body in ganglion
+postganglionic neuron to effector
-Stimulates or inhibits cardiac or smooth muscle or glands
-Controls visceral organ function to support homeostasis