The beginning of the cardiac cycle is when the
A. ventricles fill with blood.
B. two semilunar valves close.
C. atria contract.
D. atria fill with blood.
E. ventricles contract.
Answer: C
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Which action leads to the closure of the right atrioventricular valve?
A. Contraction of the right atrium B. Contraction of the left atrium C. Contraction of the right ventricle D. Relaxation of the right ventricle E. Relaxation of the left atrium
The life span of a red blood cell is 100 to 120 days
Indicate whether the statement is true or false
The study of the anatomical organization of specific areas of the body is called ________ anatomy
A) gross B) surface C) systemic D) regional E) clinical
Follicle cells synthesize a protein called
A) calcitonin. B) thyroglobulin. C) transthyretin. D) albumin. E) colloid.