Chamberlain bios 252 exam 1 Latest Update

Chamberlain bios 252 exam 1 Latest Update

• 250 Questions and 100%

Verified Correct Answers Guaranteed A+

1st step at neuromuscular junction - CORRECT ANSWER: AP (action potential) travels down the axon to the axon terminal

1st step of contraction cycle - CORRECT ANSWER: myosin head hydrolyzes ATP & become energized & oriented

1st step of muscle relaxation - CORRECT ANSWER: Once the nerve impulses stops

the leftover Ach is broken down by ACHase (steps)

• muscle fiber membrane is no longer stimulated

1st step of nerve conduction - CORRECT ANSWER: polarization

• sodium outside, potassium inside

1st step of sliding filament theory - CORRECT ANSWER: myosin pulls on actin, causing thin filament to slide inward

• ratchet along filaments

2nd step at neuromuscular junction - CORRECT ANSWER: electrical gated Ca2+

channels open & Ca2+ enters axon terminal

2nd step of contraction cycle - CORRECT ANSWER: myosin head binds to actin,

forming a cross-bridge

2nd step of nerve conduction - CORRECT ANSWER: resting potential

• nothing happens
• waiting for impulse

2nd step of relaxation - CORRECT ANSWER: potassium ions leave the muscle cell

causing repolarization

2nd step of sliding filament theory - CORRECT ANSWER: z discs move towards each

other, & sarcomere shortens

3rd step at neuromuscular junction - CORRECT ANSWER: Ca2+ causes vesicles to

release ACh into synaptic cleft

3rd step of contraction cycle - CORRECT ANSWER: myosin head pivots, pulling the

thin filament past the thick filament toward center of sarcomere (power stroke)

3rd step of nerve conduction - CORRECT ANSWER: action potential 1 / 2

• sodium ion begins to move
• impulse copies into axon

3rd step of relaxation - CORRECT ANSWER: calcium ions are actively transported back into sarcoplasmic reticulum

3rd step of sliding filament theory - CORRECT ANSWER: thanks to structural proteins, there is a transmission of force throughout the entire muscle

• resulting in whole muscle contraction

4th step of contraction cycle - CORRECT ANSWER: as myosin head binds ATP, cross- bridge detaches from actin

4th step of nerve conduction - CORRECT ANSWER: repolarization

• potassium moves out
• impulse done thru axon & myelin sheath

4th step of neuromuscular junction - CORRECT ANSWER: ACh diffuses across

synaptic cleft & bind to its receptors on the muscle

4th step of relaxation - CORRECT ANSWER: linkage b/w actin & myosin filaments break

4th step of sliding filament theory - CORRECT ANSWER: changes in I band & H zone as muscle contracts

5th step at neuromuscular junction - CORRECT ANSWER: ACh binding opens ion

channels & sodium rushes into muscle

5th step of nerve conduction - CORRECT ANSWER: hyperpolarization

• potassium & sodium have switch places
• nothing is moving
• impulse is moving to next neuron

5th step of relaxation - CORRECT ANSWER: actin & myosin filaments slide apart

6th step at neuromuscular junction - CORRECT ANSWER: if muscle reaches threshold (-55mv)at motor end plate, an AP occurs on muscle

6th step of nerve conduction - CORRECT ANSWER: refractory period

• everything is moving back to RMP

6th step of relaxation - CORRECT ANSWER: muscle fiber (sarcomere) relaxes

7th step at neuromuscular junction - CORRECT ANSWER: ACh is broken down by

acetylcholine esterase

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