Muscle Contraction Steps

Front

What ion changes the conformation of tropomyosin during muscle contraction?

Back

Calcium

Front

Which protein does calcium bind to in order to change the conformation of tropomyosin?

Back

Troponin Protein

Front

Which ion is NOT critical to muscle contraction?

Back

Phosphorus Ion

Front

Identify a protein that is NOT a myofibril protein: Trypsin, Actin, Troponin, Tropomyosin, Myosin, Titin.

Back

Trypsin is not a myofibril protein.

Front

What opens the ligand gated sodium/potassium channel?

Back

Acetylcholine binding to the channel protein.

Front

What is the role of calcium ions in muscle contraction?

Back

Calcium ions bind to troponin, causing tropomyosin to move and expose binding sites on actin.

Front

Define tropomyosin in the context of muscle contraction.

Back

Tropomyosin is a protein that blocks the binding sites on actin filaments, preventing muscle contraction until calcium binds to troponin.

Front

What is the function of troponin in muscle contraction?

Back

Troponin binds calcium ions and causes a conformational change that moves tropomyosin away from actin's binding sites.

Front

What is the role of acetylcholine in muscle contraction?

Back

Acetylcholine is a neurotransmitter that binds to receptors on muscle cells, triggering the opening of sodium/potassium channels.

Front

Explain the significance of sodium and potassium ions in muscle contraction.

Back

Sodium ions enter the muscle cell, depolarizing the membrane, while potassium ions exit, helping to reset the membrane potential after contraction.