Exploring Skeletal Muscle Histology and Sarcomere Structure

The video tutorial provides an in-depth look at skeletal muscle tissue, explaining its structure, function, and components. It covers the characteristics of muscle fibers, including the roles of actin and myosin in muscle contraction. The tutorial also details the structure of the sarcomere, the basic unit of muscle contraction, and provides a step-by-step guide to drawing it. Finally, it explains the sliding filament mechanism, which describes how muscles contract through the interaction of thick and thin filaments.

What is another name for skeletal muscle?

• Smooth muscle

• Cardiac muscle

• Involuntary muscle

• Striated muscle

Why is skeletal muscle considered voluntary?

• It contracts automatically

• It is under conscious control

• It is found in the heart

• It has a smooth appearance

What percentage of adult male weight is contributed by skeletal muscle?

• 40-50%

• 30-40%

• 20-30%

• 50-60%

What are muscle fibers made of?

• Short, round cells

• Irregular, star-shaped cells

• Long, thread-like cells

• Flat, plate-like cells

Which filament is considered the thick filament in muscle fibers?

• Actin

• Myosin

• Troponin

• Tropomyosin

What is the basic functional unit of a muscle fiber?

• Myofibril

• Sarcomere

• Fascia

• Mitochondria

Which band contains only thick filaments?

• H zone

• I band

• A band

• Z disk

What is the role of the Z disk in a sarcomere?

• It is the center of the H zone

• It contains only thin filaments

• It contains only thick filaments

• It marks the boundary of a sarcomere

During muscle contraction, what happens to the H zone?

• It disappears

• It widens

• It narrows

• It remains the same

What do myosin molecules use to pull actin filaments during contraction?

• Their feet

• Their heads

• Their tails

• Their bodies