Muscle Physiology Review

The actual muscle contraction is caused by...

• the thick myofilament pulling the thin myofilament to the M line

• the thick filament pulling the tropomyosin to the M line

• calcium binding to troponin

• calcium returning to the terminal cisternae

What causes the myosin head to release to actin?

• Calcium

• ATP

• Tropomyosin

• Acetylcholine

What happens right after the myosin head releases the actin?

• Acetylcholine floods the synapse

• ATP breaks down, myosin head returns to ready position

• Calcium returns to terminal cisternae

• The muscle contracts

Which occurs first... neuromuscular junction action or sliding filament action.

• Neuromuscular junction action

• Sliding filament action

• both happen at the same time

• they have nothing to do with eachother

When calcium leaves the terminal cisternae

• Calcium binds to actin

• The muscle contracts

• Calcium binds to troponin

• Calcium binds to myosin

When the tropomyosin is moved from the binding sites on actin...

• Calcium returns to the terminal cisternae

• The muscle contracts

• The muscle resets

• Myosin binds with actin

What two chemicals are necessary for muscle contraction to occur?

• Niacin and Potassium
• Calcium and ATP
• Sodium and Potassium
• Ach and Potassium

___ and ___ are regulatory proteins bound to actin. 

• Troponin and tropomyosin
• Myosin and actin
• Calcium and Oxygen
• Glycogen and hemoglobin

What is the structure that stores the Calcium in the muscle cell.  

• Sarcoplasm
• Sarcolemma
• Sarcoplasmic Reticulum
• Myoglobin

The neurotransmitter that signals muscle contraction is called...

• Ach
• Myosin
• Actin
• Calcium