Exploring the Muscular System

Which of the following is NOT a type of muscle tissue?

• Skeletal muscle

• Cardiac muscle

• Smooth muscle

• Connective muscle

What is the primary function of skeletal muscles?

• Pumping blood

• Facilitating movement

• Digesting food

• Regulating blood pressure

Which type of muscle is found in the walls of internal organs such as the stomach and intestines?

• Skeletal muscle

• Cardiac muscle

• Smooth muscle

• Voluntary muscle

• They bind to troponin, causing a conformational change that moves tropomyosin away from actin's binding sites.

• They provide energy for the contraction.

• They break down ATP to release energy.

• They inhibit the contraction process.

Which protein forms the thick filaments in muscle fibers?

• Actin

• Myosin

• Troponin

• Tropomyosin

What is the smallest functional unit of a muscle fiber?

• Myofibril

• Sarcomere

• Muscle fiber

• Fascicle

Which type of muscle fiber is most resistant to fatigue?

• Type I (slow-twitch)

• Type IIa (fast-twitch oxidative)

• Type IIb (fast-twitch glycolytic)

• Type III (intermediate-twitch)

During muscle contraction, which molecule provides the energy required for the process?

• Glucose

• ATP

• ADP

• Creatine phosphate

What is the role of the sarcoplasmic reticulum in muscle cells?

• It stores and releases calcium ions.

• It generates ATP.

• It synthesizes proteins.

• It transports oxygen.

Which of the following statements about cardiac muscle is true?

• It is under voluntary control.

• It has a single nucleus per cell.

• It is striated and branched.

• It fatigues quickly.