Drugs called calcium channel blockers may be used to lower blood pressure by causing arteries to vasodilate. How do you suppose these drugs work?
A. They prevent calcium from entering the sarcoplasmic reticulum of smooth muscle.
B. They prevent calcium from entering cardiac muscle, thus slowing down the heart rate.
C. They prevent calcium from entering smooth muscle, thus allowing the muscle to relax.
D. They prevent calcium from exiting the sarcoplasmic reticulum in skeletal muscle.
E. They stimulate the calcium pump in smooth muscle, thus removing calcium from the calmodulin.
Answer: C
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Answer the following statement true (T) or false (F)
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