Nervous System 2

Question 1

What are the divisions of the peripheral nervous system

Answer 1

Sensory/ afferent division
Motor/efferent division splits into Visceral Motor and Somatic Motor division.

Visceral Motor Splits into Sympathetic and parasympathetic

Also the Enteric

Question 2

Define Afferent

Answer 2

carrying information into the central nervous system, usually considered synonymous with sensory information

Question 3

Define Efferent

Answer 3

carrying information away from the central nervous system, usually considered synonymous with motor information

Question 4

Define Somatic

Answer 4

relating to the body wall and limbs (muscles, skin, bones, joints).

Question 5

Define Visceral

Answer 5

relating to the internal organs (heart, lungs, digestive system, kidneys, reproductive system, etc.).

Question 6

What division of the nervous system controls the viscera?

Answer 6

Autonomic Nervous System

Question 7

There are two divisions of the ANS that are responsible for the maintence of homeostasis. what are they?

Answer 7

Parasympathetic(“rest and digest”/ craniosacral)

and Sympathetic (“fight or flight”/ thoracolumbar)

Question 8

Where is the parasympathetic neuron location?

Answer 8

parasympathetic preganglionic neurons arise from brain stem & from S2-S4 (Craniosacral).

Question 9

Where is the sympathetic neuron location?

Answer 9

Preganglionic sympathetic neurons arise from lateral horns (grey matter) of T1-L2 (thoracolumbar spinal cord)

Question 10

What controls the parasympathetic and sympathetic NS?

Answer 10

The hypothalamus

Question 11

What does the autonomic nervous system have control over ?

Answer 11

Circulation of the blood
Activity of the Gastrointestinal tract
Body temperature

Question 12

What organs/muscles/neurons does the ANS

Answer 12

Innervates smooth muscle, cardiac muscle and glands of internal organs (The viscera!).
Involuntary
Two neuron chain
preganglionic neurons – originate in the central nervous system (CNS); preganglionic efferent axons are lightly myelinated.
postganglionic neurons – originate in the ganglion located outside the CNS; postganglionic neurons are not myelinated

Question 13

When is the sympathetic activated?

Names some examples of your bodies reactions?

Answer 13

When the body is under conditions of emergency

Dilated pupils, increased heart rates, increased blood pressure, induced sweating

Question 14

What happens during exercise?

eg. sympathetic or parasympathetic

Answer 14

sympathetic vasoconstriction shunts blood from the skin and digestive viscera to the heart, brain & skeletal muscles

Question 15

What is the role of the parasympathetic nervous system?

Answer 15

Conserves body energy and maintains body activities at basal levels - homeostasis

Question 16

Is inhibition of the pancreatic enzymes sympathetic or parasympathetic?

Answer 16

sympathetic

Question 17

Is dilation of the iris sympathetic or parasympathetic?

Answer 17

sympathetic

Question 18

Compare the sympathetic and parasympathetic neurons .

Which has the longer preganglionic neuron?

Answer 18

Parasympathetic

Question 19

Compare the sympathetic and parasympathetic neurons .

Where is the gap between pre and postganglionic neuron?

Answer 19

Sympathetic- close to spinal cord

Parasympathetic- close to organ it innervates

Question 20

Compare the sympathetic and parasympathetic neurons .

Which receptors are used?

Answer 20

Sympathetic - usually Alpha and beta adrenergic but can be Muscarinic receptor
Parasympathetic- Muscarinic

Question 21

Compare the features between autonomic and somatic motor systems.
How many Neurons?
Are they myelinated?

Answer 21

Somatic- one neuron myelinated, end is skeletal muscle

Autonomic- 2 neuron, myelinated then unmyelinated

Question 22

How many pairs of nerves are in the spine.

What are they?

Answer 22

31 pairs 
8 cervical nerves 
12 thoracic nerves 
5 lumbar 
5 sacral 
1 coccygeal

Question 23

What is plexi?

Answer 23

The form nerves take when they innervate from limbs

Question 24

How does the cauda equina form?

Answer 24

The bundle of posterior nerves are caused by the bone of the vertebral column elongating more than the spinal cord

Question 25

Sensory or Motor?
Dorsal Root
Ventral Root

Answer 25

Dorsal Root- sensory

Ventral Root- motor

Question 26

What is the name given to peripheral nerves in the head and neck?

Answer 26

Cranial nerves

emerge from the brainstem

Question 27

Describe the structure of the spinal nerve

Answer 27

Roots that join to form mixed spinal nerves
Each segments of the cord gives rise to a pair of spinal nerves that consists of axons of

motor/sensory/sympathetic neurons

Question 28

Describe the role of the Dermatomes and myotomes

Answer 28

Provides sensory and motor supply of an adjacent muscle mass (myotome) and the cutaneous supply of an area of skin (dermatome).

Question 29

Define reflex

Answer 29

rapid, involuntary motor response to a stimulus.

Question 30

Define reflex arc

Answer 30

receptor, sensory neuron, integration centre, motor neuron, and effector

Question 31

Define spinal reflex

Answer 31

somatic spinal reflexes provides information on integrity of the reflex pathway and degree of excitability of the SC

Question 32

Define motor neurone

Answer 32

a motor neuron and all the skeletal muscle fibres it innervates (these all contract together).

Question 33

The finer the movement the _____ the muscle fibres/motor unit

Answer 33

The finer the movement the fewer the muscle fibres/motor unit