Physiology- neuromuscular junction and motor units

Question 1

what is the highest level of intergration?

a. spinal cord
b. subcortical
c. cortical

Answer 1

c.corticial

Question 2

homeostasis and reflex actions are found at which level of intergration?

a. cortical
b. subcortical
c. spinal cord

Answer 2

c.spinal cord

Question 3

reproduction is found at which level of intergration?

a. cortical
b. subcortical
c. spinal cord

Answer 3

b.subcortical

Question 4

science philosophy and art are found at which level of intergration?

a. cortical
b. subcortical
c. spinal cord

Answer 4

a.cortical

Question 5

lateral subcortical pathways and the lateral cerebellum represents which level of intergration?

a. cortical
b. subcortical
c. spinal cord

Answer 5

a.cortical

Question 6

medial and ventral subcorticall pathways and the lateral cerebellum represents which level of intergration?

a. cortical
b. subcortical
c. spinal cord

Answer 6

b.subcortical

Question 7

what is the function of choline acetyltransferase?

a. break down choline
c. combine acetyl coA and choline to make acetyl choline
d. break down acetyl coA
e. break down acetyl choline

Answer 7

c.combine acetyl coA and choline to make acetyl choline

Question 8

what is lost at the neuromuscular junction?

a. boutons
b. myelin sheath
c. schwann cells

Answer 8

b.myeli sheath

Question 9

where do boutons terminate?

a. motor end plate
b. spinal cord
c. neuromuscular junction

Answer 9

a.motor end plate

Question 10

what type of receptors are found on the post synaptic membrane?

a. muscarinic Ach
b. nicotinic Ach
c. muscarinic adrenergic
d. nicotinic adrenergic

Answer 10

b. nicotinic Ach

Question 11

which of these is the correct series of events when Ach binds to a post synaptic nicotinic Ach receptor?

a. sodium channels close, calcium and potassium channels open
b. sodium channels and potassium channeles open, calcium channels close
c. sodium , calcium and potassium channels open
d. sodium, calcium and potassium close

Answer 11

c.sodium , calcium and potassium channels open

Question 12

cations

Answer 12

positively charged

Question 13

anions

Answer 13

negatively charged

Question 14

what does the minature end plate potential refer to?

a.quantal release of Ach at rest = 0.5mV

B.quantal release of sodium at rest = 0.5mv

C. quantal release of calcium at rest = 0.5 mV

Answer 14

a.quantal release of Ach at rest = 0.5mV

Question 15

What type of channels are present at the T tubules?

a. potassium
b. acetyl gated sodium channels
c. voltage gated calcium channels

Answer 15

d.voltage gated calcium channels

Question 16

which receptors that release calcium are found on the sarcoplasmic reticulum?

a. nicotinic
b. ryanodine
c. muscarinic

Answer 16

b.ryanodine

Question 17

due to the action of acetylcholine esterase how long does Ach persist in the synapse for?

a. milliseconds
b. microseconds
c. seconds

Answer 17

a.milliseconds

Question 18

how does botox cause flaccid paralysis?

a. alter Ach binding
b. change activity of Ach esterase
c. reduce Ach release
d. increase Ach release

Answer 18

c.reduce Ach release

Question 19

what type of drug is pancuronium?

a. non compettive antagonist of nicotinic Ach receptors
b. competieve antagonist of nicotinic Ach receptors
c. competive agonist of nicotinic Ach receptors
d. non competeive agonist of nicotinic Ach receptors

Answer 19

b . competive antagonist of Ach receptors

Question 20

what is the mechanism of treatment of myasthenia gravis?

a. alter Ach binding
b. change activity of Ach esterase
c. reduce Ach release
d. increase Ach release

Answer 20

b.change activity of Ach esterase

increased Ach at synapse

Question 21

vomiting, diarrhoea, bronchoconstriction, brachycardia, spasms and paralysis are symptoms of excess of what substance?

a. adrenaline
c. acetylcholine
d. sodium
e. acetylcholine esterase

Answer 21

c.acetylcholine

Question 22

patient suffering muscle weakness. diagnosed with myasthenia gravis, an autoimmune condition. in this condition santibodies are produced against which structures?

a. muscarinic ach receptors
b. nicotinic ach receptors
c. ryanodine receptors
d. voltage gated sodium channels

Answer 22

b.nicotinic ach receptors

Question 23

which of these statements is correct for myasthenia gravis?

a. unchanged ach quantaties, too few receptors
b. too little ach, normal amount of receptors
c. too little ach, too few receptors

Answer 23

a. unchanged Ach quantities , too few receptors

Question 24

In Eaton Lambert syndrome anybodies are produced against which structure?

a. ryanodine receptors
b. calcium channels in the nerve terminal
c. sodium channels
d. nicotinic ach receptors

Answer 24

b.calcium channels in the nerve terminal

Question 25

which best describes the effect of eaton lambert syndrome?

.a.production of an end plate potential too small to cause AP

b. insufficient release of Ach

Answer 25

b.insufficient release of Ach

Question 26

what is the motor unit?

a. one motor neuron and all the fibres it innervates
b. one fibre and all the motor neurons innervating it
c. the number of fibres needed to be activated for a muscle to contract

Answer 26

a.one motor neuron and all the fibres it innervates

Question 27

a small motor unit ratio would be found in what type of muscle?

a. large muscle
b. muscles with fine control
c. small muscles
d. muscles with little control

Answer 27

b.muscles with fine control