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
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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)
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
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
Which of the following structures is considered part of the lower respiratory tract?
A. Nose B. Lungs C. Pharynx D. Larynx