A&P Muscular System Structure and Physiology of Contraction 2023

Front

What is an aponeurosis?

Back

A thin sheet of dense connective tissue that connects muscle to bone.

Front

What does perimysium enclose?

Back

Connective tissue that encloses bundles of muscle fibers.

Front

What is the H zone of a sarcomere?

Back

The center of the A band where only thick myofilaments are found.

Front

What is the M line in a sarcomere?

Back

The center of the A band where the attachment site for thick (myosin) myofilaments is located.

Front

What is a neuromuscular junction?

Back

The location at which an axon terminal meets the sarcolemma of a muscle fiber.

Front

What is the function of the sarcoplasmic reticulum?

Back

It stores calcium ions and releases them during muscle contraction.

Front

What are myofibrils?

Back

Long, thread-like structures within muscle fibers that contain the contractile proteins actin and myosin.

Front

What is the role of actin in muscle contraction?

Back

Actin is a thin myofilament that interacts with myosin to facilitate muscle contraction.

Front

What is the role of myosin in muscle contraction?

Back

Myosin is a thick myofilament that pulls on actin to shorten the muscle fiber during contraction.

Front

What is the sliding filament theory?

Back

A theory that explains muscle contraction as the sliding of actin and myosin filaments past each other.