Muscular System Review

Front

What is the function of the Infraspinatus muscle?

Back

The Infraspinatus muscle is responsible for the external rotation of the shoulder and stabilization of the shoulder joint.

Front

What are thin filaments in muscle fibers?

Back

Thin filaments are primarily composed of actin, which plays a crucial role in muscle contraction.

Front

Identify the sartorius muscle.

Back

The sartorius is a long, thin muscle that runs down the length of the thigh and is involved in flexing, abducting, and laterally rotating the hip.

Front

What is the role of actin in the sarcomere?

Back

Actin is a protein that forms thin filaments in the sarcomere and is essential for muscle contraction.

Front

What does it mean when a sarcomere is contracting?

Back

When a sarcomere is contracting, it means that the muscle fibers are shortening, leading to muscle contraction.

Front

Define the term 'sarcomere'.

Back

A sarcomere is the basic structural and functional unit of a muscle fiber, defined as the segment between two Z lines.

Front

What is the role of myosin in muscle contraction?

Back

Myosin is a thick filament that interacts with actin to produce muscle contraction through the sliding filament mechanism.

Front

Explain the sliding filament theory.

Back

The sliding filament theory describes how muscle fibers contract by the sliding of actin and myosin filaments past each other.

Front

What is the significance of troponin in muscle contraction?

Back

Troponin is a protein that binds calcium ions and helps regulate muscle contraction by moving tropomyosin away from actin binding sites.

Front

What is the function of tropomyosin in muscle fibers?

Back

Tropomyosin is a protein that blocks the binding sites on actin filaments, preventing muscle contraction until calcium ions are present.