Muscle Contractions Review

Front

Which two chemicals allow myosin and actin to interact?

Back

ATP and Calcium are essential for the interaction between myosin and actin during muscle contraction.

Front

What is the ability of muscle to shorten and produce tension at its ends?

Back

Contractibility is the ability of muscle fibers to shorten and generate force.

Front

Which myofilament is thick and dark?

Back

Myosin is the thick and dark myofilament responsible for muscle contraction.

Front

What structure in the muscle disperses the signal out to each muscle fiber?

Back

T-Tubules (transverse tubules) are responsible for transmitting the action potential to muscle fibers.

Front

Which myofibril is thin and light?

Back

Actin is the thin and light myofilament that works with myosin during muscle contraction.

Front

What is the role of ATP in muscle contraction?

Back

ATP provides the energy required for myosin to bind to actin and perform the power stroke.

Front

What is the function of calcium ions in muscle contraction?

Back

Calcium ions bind to troponin, causing a conformational change that allows myosin to interact with actin.

Front

Define the term 'sarcomere'.

Back

A sarcomere is the basic contractile unit of muscle fibers, defined by the area between two Z lines.

Front

What is the significance of the sarcoplasmic reticulum in muscle contraction?

Back

The sarcoplasmic reticulum stores calcium ions and releases them during muscle contraction.

Front

Explain the sliding filament theory.

Back

The sliding filament theory describes how myosin and actin filaments slide past each other to shorten the muscle during contraction.