Muscle Contraction

What is the most basic level of the muscular structure?

• Sarcolemma

• Sarcomeres

• Fibers

• fascicles

The actin is labeled here as _______.

• AD

• AC

• BC

• AB

The myosin is labeled here as _______.

• BD

• AC

• BC

• AB

Ca2+ released by sarcoplasmic reticulum will bind to

• Actin

• Troponin

• Myosin

• Tropomyosin

a neurotransmitter that stimulates skeletal muscle fibers

• dopamine

• serotonin

• acetylcholine

• epinephrine

During a muscle contraction...

• actin pulls on the myosin

• myosin pulls on the actin

• tropomyosin pulls on the myosin

• troponin pulls on the actin

Which of the following substances are absolutely necessary for muscle contraction?

• ATP and Na⁺

• ATP and Ca²⁺

• ADP+P

• ADP and Ca²⁺

What is the name of the neurotransmitter released at a neuromuscular junction?

• Calcium

• Acetylcholine

• Dopamine

• Troponin

Which ion, when present, changes the conformation of tropomyosin?

• Calcium
• Sodium
• Potassium
• Lithium

Reorder the following

• Nervous system sends an action potential.

• Acetylcholine binds to the nicotinic receptor on the muscle cell which sends a signal.

• Sarcoplasmic Reticulum releases Calcium

• Nerve Cell releases Acetylcholine into the neuromuscular junction.

• Signal is muscle cell reaches the T-Tubule.