The first heart sound, "lub," is made by

A. closure of the semilunar valves.
B. contraction of the ventricles.
C. closure of the AV valves.
D. contraction of the atria.


Answer: C

Anatomy & Physiology

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The percent of oxygen saturation of hemoglobin when the temperature is 38 degrees centigrade is

A) greater than the percent of oxygen saturation of hemoglobin when the temperature is 43 degrees centigrade. B) less than the percent of oxygen saturation of hemoglobin when the temperature is 43 degrees centigrade. C) equal to the percent of oxygen saturation of hemoglobin when the temperature is 43 degrees centigrade. D) equal to the percent of oxygen saturation of hemoglobin when the temperature is 20 degrees centigrade. E) equal to the percent of oxygen saturation of hemoglobin when BPG levels are high.

Anatomy & Physiology

These figures show a frontal view of the abdominopelvic cavities. Which number indicates the epigastric region?

?A.  1?B.  2?C.  3?D.  4?E.  5

Anatomy & Physiology

The hairpin-shaped segment of the nephron is the

A) loop of Henle. B) proximal tubule. C) distal tubule. D) minor calyx. E) vasa recta.

Anatomy & Physiology

the beta cells in the pancreas secrete

What will be an ideal response?

Anatomy & Physiology