Which of the following events result in the first heart sound?
A) The AV valves close.
B) The semilunar valves open.
C) The AV valves open.
D) The atria contract.
E) The semilunar valves close.
A) The AV valves close.
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The muscle tissue that shows no striations is ________ muscle
A) skeletal B) cardiac C) smooth D) voluntary E) multinucleated
This type of muscle tissue is found in the stomach.
A. Skeletal B. Voluntary C. Smooth D. Cardiac
The prefix an- means _____. Select one:
a. without b. with c. against d. missing
What is the difference in function between the smooth and rough endoplasmic reticulum (ER)?
A. The rough ER helps with cellular movements, while the smooth ER does not. B. The rough ER produces ATP, while the smooth ER does not. C. The rough ER conducts lipid synthesis, while the smooth ER conducts protein synthesis. D. The rough ER conducts protein synthesis, while the smooth ER conducts lipid synthesis. E. The rough ER breaks down lipids, while the smooth ER breaks down proteins and debris.