Which of the following affects the rate of diffusion

through a selectively permeable membrane?
I. concentration gradient
II. temperature
III. molecular size
a. I only
b. II only
c. I and II
d. II and III
e. I, II, and III


Answer: e

Biology & Microbiology

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The term facultative refers to

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Which of the following elements is often growth limiting for organisms because of its limited availability?

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Insulin is a small protein that regulates blood sugar level and is given to patients who suffer from diabetes. Many years ago, diabetics were given insulin that had been purified from pig pancreas

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Biology & Microbiology