Neuromuscular Control

Question 1

Divisions of the Peripheral Nervous System

Answer 1

Afferent

Efferent

Question 2

afferent (2)

Answer 2

sensory neurons

to CNS

Question 3

afferents to the CNS (2)

Answer 3

somatic

visceral

Question 4

efferent (2)

Answer 4

motor neurons

away from the CNS

Question 5

efferents away from the CNS (2)

Answer 5

autonomic

somatic

Question 6

somatic (2)

Answer 6

innervates skeletal muscle

motor neurons

Question 7

Motor Units

Answer 7

Motor neuron and all the fibers it innervates

Question 8

Motor end plates synapse with

Answer 8

muscle fibers

Question 9

— carry the AP along the membrane

Answer 9

VGNa+

Question 10

Ach Nicotinic Receptors on Skeletal Muscle:

Stimulation leads to

Answer 10

change in membrane potential

Question 11

change in membrane potential is also known as

Answer 11

end plate potential

Question 12

end plate potential usually always causes

Answer 12

an action potential

Question 13

action potential moves down

Answer 13

t tubules

Question 14

excitation contraction coupling

Question 15

Skeletal Muscle Organization Actin and Myosin crosslink for

Answer 15

muscle shortening

Question 16

— induces muscle contraction via interaction of myosin and actin

Answer 16

Calcium

Question 17

Duchenne Muscular Dystrophy results from

Answer 17

Mutations in DMD gene encoding dystrophin

Question 18

Mutations in DMD gene encoding dystrophin usually connects

Answer 18

cytoskeleton of the fiber to the extracellular matrix

Question 19

Termination of contraction (3)

Answer 19

Acetylcholine breakdown, synthesis, and packaging

Question 20

Relaxation of the muscle- Reuptake of —

Answer 20

Calcium

Question 21

Relaxation of the muscle- Reuptake of Calcium (3)

Answer 21

SERCA
NCX
Calsequestrin

Question 22

A 32 year-old male is having a routine surgery to repair the anterior cruciate ligament in the right knee. After dosing with anesthetic (sevoflurane), the patient became rigid, heart rate rose to 130 bpm, blood pressure became 70/56, breathing rate of 20, and temperature was
106 F. The anesthesiologist indicated that this might be a case of malignant hyperthermia. A condition in which a patient has a mutation in the ryanodine receptor which causes the receptor to become active in the presence of certain anesthetics.

What do you think was the primary cause for the 106 degree temperature during the crisis?

a. Immune response to the anesthetic
b. Increased heart rate
c. Lowered blood pressure causing a decrease in blood circulation
d. Increase in muscle metabolism
e. Increase in capillary permeability
f. Increase in central nervous system activity

Question 23

A 32 year-old male is having a routine surgery to repair the anterior cruciate ligament in the right knee. After dosing with anesthetic (sevoflurane), the patient became rigid, heart rate rose to 130 bpm, blood pressure became 70/56, breathing rate of 20, and temperature was
106 F. The anesthesiologist indicated that this might be a case of malignant hyperthermia. A condition in which a patient has a mutation in the ryanodine receptor which causes the receptor to become active in the presence of certain anesthetics.

Which of the following could be used to treat the patient?

a. Increase in ventilation rate
b. Increase in heart rate
c. Inject sevoflurane
d. Block calcium release channels in skeletal muscle

Question 24

causes of Myasthenia Gravis (2)

Answer 24

• Autoimmune Disease

- Antibody production to Ach nicotinic receptors

Question 25

symptoms of Myasthenia Gravis (1)

Answer 25

-Weakening of skeletal muscles

Question 26

A 55 year old woman visits her physician because of double vision, eyelid droop, difficulty chewing and swallowing, and general weakness in her limbs. Symptoms are made worse with exercise. The physician orders a tensilon test in which the patients perform repeated muscle movements before and after injection of tensilon or placebo (tensilon is an Ach esterase inhibitor similar tophysostigmine). The woman performs the activities much better after the tensilon. Without other testing being performed which of the following is the most likely diagnoses?

1. Botulinum toxicity
2. Myasthenia Gravis
3. Defect in calcium channels in the presynaptic terminal of motor neurons
4. Muscarine (mushroom) poisoning

Question 27

Curare poisoning
ACh release:
ACh Esterase activity:
Frequency of skeletal muscle contraction:
HR change:

Question 28

Sarin (neve) gas poisoning 
ACh release:
ACh Esterase activity:
Frequency of skeletal muscle contraction:
HR change:

Question 29

Botulism 
ACh release:
ACh Esterase activity:
Frequency of skeletal muscle contraction:
HR change:

Question 30

Myasthenia Gravis 
ACh release:
ACh Esterase activity:
Frequency of skeletal muscle contraction:
HR change: