Intro CNS & PNS

Question 1

Differentiate CNS & PNS

Answer 1

CNS:
Brain and spinal cord
Neuronal cell bodies = nucleus or gray matter
Neuronal axons = tracts or white matter

PNS:
Everything else
Neuronal cell bodies = ganglia
Neuronal axons = nerves

Question 2

Afferent vs Efferent fiberes

Answer 2

Afferent carries information towards CNS (sensory)

Efferent carries information away from CNS (motor)

Question 3

Define brainstem and its importance

Answer 3

stem of brain. Contains pons and a small region of medulla that is very important for regulatory centers

Question 4

Planes of section / curvature in the brain

Answer 4

Sagittal - right down the middle (left and right halves)
Transverse - Separating superior and inferior
Coronal - Separating anterior and posterior
Because of the brain stem, coronal planes are curved in order to include it.

Question 5

Planes of section / curvature in the spinal cord

Answer 5

Dorsal - towards posterior

Ventral - towards anterior

Question 6

Describe Somatic Motor System

Answer 6

Innervates skeletal muscle
Unidirectional
Stimulations = contraction
No active relaxation
Acetylcholine is neurotransmitter

Question 7

Chemicals involved in Somatic motor system

Answer 7

Acetylcholine is neurotransmitter
Agonist - Nicotine (at ganglia)
Antagonist - curare (at ganglia)

Question 8

Describe Autonomic nervous system

Answer 8

Innervates smooth muscle, cardiac muscle, glands, immune system
Bidirectional (down and up)
Composed of parasympathetic and sympathetic.

Question 9

List the segments of the spinal cord and their characteristics

Answer 9

31 Total - Each contains 2 sets of ipsilateral neurons (1 afferent, 1 efferent)
8 Cervical - ventral gray enlargement (for upper limbs)
12 Thoracic -
5 Lumbar - ventral gray enlargement (for lower limbs)
5 Sacral
1 Coccygeal

Question 10

Parasympathetic vs Sympathetic

Answer 10

Sympathetic = fight or flight
Parasympathetic = Rest and digest
Most organs/tissues are innervated in opposite directions (both)

Question 11

Chemicals involved in autonomic motor system (in ganglia)

Answer 11

For both sympathetic and parasympathetic
Neurotransmitter - Acetylcholine
Agonist: Nicotine
Antagonist: hexamethonium

Question 12

Parasympathetic End vs Sympathetic End

Neurotransmitter, Agonist, & Antagonist

Answer 12

Parasympathetic end:
Neurotransmitter - Acetylcholine
Agonist - muscarine
Antagonist - Atropine

Sympathetic end:
Neurotransmitter - Norepinephrine

Question 13

Nuclear Ambiguus ?

Answer 13

Cranial Nerves 9-11 responsible for speaking and swallowing

Question 14

Parasympathetic preganglionic neuron locations (and ganglia)

Answer 14

> Cranio Sacral
III, VII, IX, X
Intermediate Gray S2-S4

Ganglia: at/near effector tissue
Long pregang. fiber and short post gang. fiber

Question 15

Where do you find ALL motor neurons?

Answer 15

Ventral Gray, bilaterally, of every spinal segment

Cranial nerve 3,4,5,6,7, Ambiguus, 12

Question 16

Dorsal vs Ventral Gray

Answer 16

Doral Gray = Sensory

Ventral Gray = Motor

Question 17

Sympathetic preganglionic neuron locations (and ganglia)

Answer 17

Thoracic & Lumbar Chord
Intermediate lateral gray (project laterally)

Ganglia:
sympathetic chains at side of spinal cord
Short pregang. fiber and long post gang. fiber

Question 18

How does Adrenal Medulla fit in the nervous system?

& Catecholamines, Biogenic amines

Answer 18

Acts as a ganglia for Sympathetic NS.
Neurotransmitter - Acetylcholine
Agonist - Nicotine
Antagonist - Hexamethonium

Secretes neurotransmitter into capillary bed - this is called a Hormone

Secretes:
Epinephrine

Question 19

norepinephrine and Epinephrine go to which receptors

Answer 19

Nor - Alpha receptors

Epi - Beta Receptors

Question 20

Ptosis
Miosis
Anhydrosis

Answer 20

Ptosis = eyelid droop
Miosis = pupillary constriction
Anhydrosis = lack of sweating

Question 21

Horner’s syndrome produces what kind of signs?

Answer 21

Ipsilateral

Question 22

How do the autonomic pathways affect pupil size?

Answer 22

Predominant ParaS = Pupil constriction (miosis)

Predominat Symp = Pupil Dilation (mydriasis)

Question 23

Cause of Horner’s’ syndrome?

Answer 23

Lesion in sympathetic nerves
Can be in Superior cervical ganglion
Intermedialateral gray T1/T2
Descending hypothalamus tract in cervical cord
Descending hypothalamus tract in brainstem