Muscle contraction quiz/video

Which type of muscle tissue is characterized by branched, striated fibers with intercalated discs and involuntary control?

• Skeletal muscle

• Smooth muscle

• Cardiac muscle

• Connective muscle

Which statement is correct?

HINT- involuntary doesn't require conscious control, voluntary you chose to contract

• Smooth muscle is involuntary while cardiac and skeletal are voluntary

• Smooth muscle is voluntary while cardiac and skeletal are involuntary

• Smooth & cardiac are involuntary muscles while skeletal muscles are voluntary.

• Skeletal is involuntary while cardiac and smooth muscle is voluntary

Which of the following is NOT a general characteristic of all muscle tissue?

• Extensibility

• Elasticity

• Voluntary control

• Excitability

What are the long, cylindrical structures found inside a muscle fiber that contain repeating sections called sarcomeres?

• Myofibrils

• Tendons

• Ligaments

• Fascicles

What are the thin filaments in a sarcomere primarily composed of?

• Myosin

• Actin

• Troponin

• Tropomyosin

What happens to the thick and thin filaments themselves during muscle contraction according to the sliding filament model?

• They shorten significantly.

• They lengthen to increase muscle size.

• They slide past each other without shortening.

• They break down and reform.

What is the primary role of ATP in the cross-bridge cycle of muscle contraction?

• To cause the myosin head to bind to actin.

• To provide energy for the power stroke.

• To cause the myosin head to detach from actin.

• To block the actin binding sites.

What ion is released to initiate muscle contraction by binding to troponin, causing tropomyosin to move and expose myosin binding sites on actin?

• Sodium ions

• Potassium ions

• Calcium ions

• Chloride ions