A significant change in vertebrate hearts began when
a. the ancestors of whales returned to the oceans.
b. flight evolved in birds.
c. reptiles moved onto land.
d. air-breathing fish evolved.
e. amphibians transitioned to life on land and in water.
D
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During its mitotic phase a cell is
A. duplicating its DNA. B. growing in size. C. dividing. D. undergoing maintenance.
Roughly 98% of the potassium content of the body lies within which of the following?
A) lymph B) cerebrospinal fluid C) cytosol D) serous fluids E) aqueous humor
The pH of the blood is slightly basic. Which of the following describes this pH?
A. 4.7 B. 7.4 C. 12.6 D. 6.4
Normally, the uterus is angled anterosuperiorly within the body, a position referred to as ________.
Fill in the blank(s) with the appropriate word(s).