Autonomic Nervous System

Question 0

Located in paravertebral chain

Answer 0

Sympathetic

Question 1

located in or near the effector organs, type of ANS

Answer 1

Parasympathetic

Question 2

Preganglionic fibers synapse directly on chromaffin cells in the __________
■ The chromaffin cells secrete epinephrine (80%) and norepinephrine (20%) into thecirculation. What is the organ described?

Answer 2

Adrenal Medulla

Question 3

tumor of the adrenal medulla that secretes excessive amountsof catecholamines and is associated with increased excretion of 3-methoxy-4-hydroxymandelic acid (VMA).

Answer 3

pheochromocytoma

Question 4

are located on vascular smooth muscle of the skin and splanchnic regions, the gas-trointestinal (GI) and bladder sphincters, and the radial muscle of the iris.
■ produce excitation (e.g., contraction or constriction).
■ are equally sensitive to norepinephrine and epinephrine. However, only norepi-nephrine released from adrenergic neurons is present in high enough concentra-tions to activate α1 receptors.
■ Mechanism of action: Gq protein, stimulation of phospholipase C, and increase ininositol 1,4,5-triphosphate (IP3) and intracellular [Ca2+].

Answer 4

Alpha 1 receptor

Question 5

are located on vascular smooth muscle of skeletal muscle, bronchial smooth mus-cle, and in the walls of the GI tract and bladder.
■ produce relaxation (e.g., dilation of vascular smooth muscle, dilation of bronchi-oles, relaxation of the bladder wall).
■ are more sensitive to epinephrine than to norepinephrine.
■ are more sensitive to epinephrine than the α1 receptors.

Answer 5

Beta 2 receptors

Question 6

are located in the autonomic ganglia of the sympathetic and parasympatheticnervous systems, at the neuromuscular junction, and in the adrenal medulla. The receptors at these locations are similar, but not identical.
■ are activated by ACh or nicotine.
■ produce excitation.
■ are blocked by ganglionic blockers (e.g., hexamethonium) in the autonomic ganglia,but not at the neuromuscular junction.
■ Mechanism of action: ACh binds to α subunits of the nicotinic ACh receptor. Thenicotinic ACh receptors are also ion channels for Na+ and K+.

Answer 6

Nicotinic receptors

Question 7

are located in the heart, smooth muscle, and glands.
■ are inhibitory in the heart (e.g., decreased heart rate, decreased conduction velocityin AV node).
■ are excitatory in smooth muscle and glands (e.g., increased GI motility, increasedsecretion).
■ are activated by ACh and muscarine.
■ are blocked by atropine.
■ Mechanism of action:
(1) Heart SA node: Gi protein, inhibition of adenylate cyclase, which leads to openingof K+ channels, slowing of the rate of spontaneous Phase 4 depolarization, anddecreased heart rate.
(2) Smooth muscle and glands: Gq protein, stimulation of phospholipase C, and increasein IP3 and intracellular [Ca2+]

Answer 7

Muscarinic receptors

Question 8

Pacinian corpuscles
■ Joint receptors
■ Stretch receptors in muscle
■ Hair cells in auditory and vestibular systems■ Baroreceptors in carotid sinus

Answer 8

Mechanoreceptors

Question 9

Rods and cones

Answer 9

Photoreceptors

Question 10

exception is in the photoreceptor, where light causes decreased inward currentand hyperpolarization. True or false?

Answer 10

True

Question 11

processes sensations of fine touch, pressure, two-point discrimination, vibration, andproprioception.
■ consists primarily of group II fibers.
■ Course: primary afferent neurons have cell bodies in the dorsal root. Their axonsascend ipsilaterally to the nucleus gracilis and nucleus cuneatus of the medulla.From the medulla, the second-order neurons cross the midline and ascend to thecontralateral thalamus, where they synapse on third-order neurons. Third-orderneurons ascend to the somatosensory cortex, where they synapse on fourth-order neurons.

Answer 11

Dorsal column system

Question 12

Onion-like structures in the 
subcutaneous skin
(surrounding unmyelinated
nerve endings)
Vibration; tapping
Rapidly adapting

Answer 12

Pacinian corpuscles

Question 13

Present in nonhairy skin
Velocity
Rapidly adapting

Answer 13

Meissner’s

Question 14

Farsighted. Light focuses behind the retina and is corrected with aconvex lens.

Answer 14

Hypertropia

Question 15

A.Cutting the optic nerve causes blindness in the ipsilateral eye.

b. Cutting the optic chiasm causes heteronymous bitemporal hemianopia.
c. Cutting the optic tract causes homonymous contralateral hemianopia.
d. Cutting the geniculocalcarine tract causes homonymous hemianopia with macular sparing.

Which among is or are true?

Answer 15

All are true

Question 16

are arranged in parallel with extrafusalfibers. They detect both static and dynamic changes in muscle length.

Answer 16

Muscle spindles

Question 17

Which hormone increases metabolic rate and heat production by stimulating Na+, K+-adenosine triphosphatase (ATPase).

Answer 17

Thyroid hormones

Question 18

most potent mechanism for increasing heat production.

Answer 18

Shivering

Question 19

T or F.
Cold is to anterior hypothalamus control
Heat is to posterior thalamus control

Answer 19

False. The reverse is true