Muscle Review

Front

Pectoralis major

Back

A large muscle in the upper chest that is responsible for the movement of the shoulder joint.

Front

Triceps brachii

Back

A muscle located at the back of the upper arm, responsible for extending the elbow.

Front

In order for a muscle to contract, cross-bridges must form between myosin heads and active sites within a sarcomere. Active sites are found on:

Back

Actin molecules.

Front

Latissimus dorsi

Back

A large, flat muscle on the back that helps in the movement of the shoulder and arm.

Front

Biceps brachii

Back

A muscle located on the front of the upper arm, responsible for flexing the elbow.

Front

What is the role of calcium ions in muscle contraction?

Back

Calcium ions bind to troponin, causing a conformational change that allows myosin heads to attach to actin.

Front

Define sarcomere.

Back

The basic contractile unit of muscle tissue, composed of actin and myosin filaments.

Front

What is the function of tropomyosin in muscle contraction?

Back

Tropomyosin blocks the active sites on actin molecules, preventing myosin from binding when the muscle is relaxed.

Front

What is the sliding filament theory?

Back

A theory that explains muscle contraction as the sliding of actin filaments over myosin filaments.

Front

What is the primary function of the deltoid muscle?

Back

To facilitate shoulder abduction, flexion, and extension.