Muscular System: Anatomy

What is the primary function of the muscular system in maintaining body position?

Posture maintenance helps maintain standing position.

What role does the muscular system play in protecting internal structures?

Support soft tissues, such as the abdominal wall protecting intestines.

How does the muscular system assist with the elimination of waste?

It guards entrances and exits with voluntary control of swallowing and waste release.

What effect does muscle energy usage have on body temperature?

Thermoregulation increases body temperature when muscles use energy.

What happens to muscles when a person is protein-deficient?

Muscles break down when protein-deficient.

What is the smallest unit of the skeletal muscle organization?

Muscle fiber (cell level).

What type of connective tissue surrounds and stabilizes each muscle fiber?

Endomysium.

What is the function of the perimysium in muscles?

Surrounds and stabilizes each fascicle.

What structure connects muscles to bones?

Tendon, formed by fusion of epimysium, perimysium, and endomysium.

What are the two types of muscle stem cells?

Myoblasts and myosatellite cells.

What organelle is responsible for muscle contraction within muscle cells?

Myofibril.

What is the role of mitochondria in muscle cells?

They release energy.

What is the basic unit of muscle contraction called?

Sarcomere.

What proteins make up the thick and thin myofilaments?

Thick myofilaments are made of myosin, and thin myofilaments are made of actin.

What happens to the A band during muscle contraction?

The A band length remains constant.

What is the sliding filament theory?

It explains how muscles contract by filaments sliding past each other without shortening.

Which bands in the sarcomere change length during contraction?

The H and I bands shorten.

What are the two proteins involved in controlling muscle contraction?

Tropomyosin and troponin.

What is the triad in muscle cells?

It is the combination of 2 terminal cisternae and 1 transverse tubule.

What is the importance of calcium (Ca²⁺) in muscle contraction?

Calcium is stored in the terminal cisternae and is essential for muscle contraction.

What is the flow of organization from smallest to largest in muscle physiology of contraction?

Myofilament, sarcomere, myofibril, muscle fiber, muscle fascicle, skeletal muscle, muscular system, human body.