Molecules that traverse a membrane against their concentration gradient do so by _______ transport.
a. active
b. passive
c. carrier-mediated
d. channel-mediated
Ans: a. active
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What will be an ideal response?
What do fats, steroids, and waxes have in common?
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Which of the following heart tissues is not part of the internal conduction system of the heart?
A. atrioventricular bundle B. sinoatrial node C. semilunar valve D. Purkinje fibers E. atrioventricular node