In a relaxed muscle fiber, what blocks the active sites on actin?


A. Tropomyosin
B. Troponin
C. Calcium ions
D. Myosin heads
E. Elastic fibers


A. Tropomyosin

Anatomy & Physiology

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A young woman is in a car accident. When she regains consciousness, she notices a sharp pain in her left arm. Looking down, she sees a bone sticking out. This is a compound fracture.

Answer the following statement true (T) or false (F)

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Which of the following is/are not part of the axial skeleton?

A. The vertebrae B. The ribs C. The sternum D. The clavicles E. The parietal bone

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Which of the following is NOT an effect of the parasympathetic nervous system?

A) bronchoconstriction B) increased sweat secretion C) decreased heart rate D) constriction of the pupil

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Which of the following structures is considered part of the lower respiratory tract?

A. Nose B. Lungs C. Pharynx D. Larynx

Anatomy & Physiology