13

Question 1

where does the Efferent subdivision of the CNS carry signals to and from?

Answer 1

away from the brain and spinal cord to the peripheral tissues

Question 2

where does the Afferent subdivision of the CNS carry signals to and from?

Answer 2

from the periphery to the CNS

Question 3

what is the feedback mechanism of the afferent division of the PNS?

Answer 3

provides sensory input to modulate efferent division function through reflex arcs that mediate a reflex action

Question 4

which PNS division is involved in reflex regulation?

Answer 4

afferent

Question 5

what are the 2 subdivisions of the efferent system of the PNS?

Answer 5

• somatic

- autonomic

Question 6

describe the function of the somatic subdivision of the efferent system

Answer 6

somatic efferent neurons are involved in the voluntary control of functions such as contraction of the skeletal muscles essential for locomotion

Question 7

describe the function of the autonomic subdivision of the efferent system

Answer 7

regulates vital bodily functions without the conscious participation of the mind

Question 8

what is the autonomic nervous system also known as

Answer 8

-visceral, vegetative, or voluntary nervous system

Question 9

the autonomic nervous system is composed of efferent neurons that innervate what sites?

Answer 9

• smooth muscle of the viscera
• cardiac muscle
• vasculature
• exocrine glands

Question 10

list 4 things the ANS controls

Answer 10

1. digestion
2. cardiac output
3. blood flow
4. glandular secretions

Question 11

the ANS is divided into what 3 divisions?

Answer 11

• sympathetic NS
• parasympathetic NS
• enteric NS

Question 12

the enteric NS is a collection of nerve fibers that innervates the:

Answer 12

gastrointestinal tract, pancreas, and gallbladder

Question 13

what is the function of the enteric NS

Answer 13

it functions independently of the CNS and controls the motility, exocrine, and endocrine secretions and microcirculation of the GI tract

Question 14

what is the enteric NS modulated by?

Answer 14

by both the sympathetic and parasympathetic nervous systems

Question 15

the ANS transmits nerve impulses from the CNS to the effector organs via

Answer 15

two types of efferent neurons: preganglionic and postganglionic

Question 16

which ANS neuron originates from the CNS and makes a synaptic connection in ganglia

Answer 16

preganglionic neuron

Question 17

what is the function of the ganglia

Answer 17

relay station between the preganglionic and postganglionic neurons

Question 18

which ANS neuron originates from the ganglia relay station, is generally non-myelinated, and terminates on effector organs

Answer 18

postganglionic neuron

Question 19

the preganglionic neurons of the sympathetic system come from the ___ regions of the spinal cord

Answer 19

thoracic and lumbar regions (T1 to L2)

-thoracolumbar

Question 20

preganglionic neurons are ____ (short/long) compared to postganglionic

Answer 20

preganglionic are short

Question 21

how many preganglionic neurons can interact with postganglionic neurons in sympathetic NS

Answer 21

because preganglionic neurons are highly branches, one preganglionic neuron can interact with many postganglionic neurons

Question 22

the preganglionic neurons of the parasympathetic NS come from what cranial nerves?

Answer 22

III-oculomotor
VII-facial
IX- glossopharyngeal
X-vagus

Question 23

what regions on the spinal cord can the preganglionic neurons from the parasympathetic system come from?

Answer 23

the sacral region (S2 to S4) of the spinal cord

-craniosacral

Question 24

in the parasympathetic NS, where do the preganglionic fibers synapse?

Answer 24

in ganglia near or on the effector organs

Question 25

what is the ratio or pre ganglion to post ganglion neurons in parasympathetic NS?

Answer 25

1:1 connection usually, enabling discrete response of this system

Question 26

the ___ nerve accounts for 90% of preganglionic parasympathetic fibers in the body

Answer 26

vagus

Question 27

postganglionic neurons from the vagus nerve innervate most of the organs in what areas of the body?

Answer 27

thoracic and abdominal cavity

Question 28

describe effects of sympathetic output

Answer 28

- increased heart rate and blood pressure - to mobilize energy stores on the body - increase blood flow to skeletal muscles and the heart - diverting blood flow from the skin and internal organs

Question 29

other results of sympathetic stimulation

Answer 29

- dilation of pupils and the bronchioles - affects GI motility - function of the bladder and sexual organs

Question 30

in addition to the direct sympathetic activation of the effector organs in the fight or flight response, what else is stimulated and what does it release?

Answer 30

adrenal medulla is stimulated to release primary epinephrine and to a lessor degree norepinephrine directly into the blood stream to promote responses in effector organs that contain adrenergic receptors

Question 31

main purpose of parasympathetic NS

Answer 31

maintains essential bodily functions, such as digestion and elimination of wastes which are required for life

Question 32

what is different about the functionality and activation of the parasympathetic NS

Answer 32

it is not a functional entity as such and it never discharges as a complete system

Question 33

what are the 2 groups of autonomic nerve fibers based on neurotransmitter released

Answer 33

- cholinergic nerves (acetylcholine released) | - noradrenergic nerves (norepinephrine released)

Question 34

what mediates the transmission of nerve impulses across autonomic ganglia in both the sympathetic and parasympathetic nervous systems

Answer 34

acetylcholine

Question 35

in the somatic NS, is transmission at the NMJ cholinergic or noradrenergic?

Answer 35

cholinergic

Question 36

2 types of cholinergic receptors | classified by their selective activation by alkaloids

Answer 36

- muscarinic | - nicotinic

Question 37

2 types of adrenergic receptors | classified by their response to Epi and Norepi

Answer 37

- alpha | - beta