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Question
The 1985 Nobel Prize in Physiology or Medicine was awarded to Michael Brown and Joseph Goldstein for their work on cholesterol metabolism. Brown and Goldstein investigated the cause of remarkably high levels of circulating cholesterol found in certain families. Just as remarkable was the high incidence of heart disease in these families. What Brown and Goldstein found was not what might be expectedthese individuals did not make too much cholesterol. Instead, most of these people had defects in receptor-mediated endocytosis (RME). What could possibly link high cholesterol levels in the blood and defective RME in these patients?
A) Cholesterol was being secreted from cells by RME at too high a rate and therefore accumulated in the blood.
B) Cholesterol was not transported into cells by RME and therefore accumulated in the blood.
C) Cholesterol was being secreted by facilitated diffusion at too high a rate and therefore accumulated in the blood.
D) Cholesterol was not transported into cells by active transport proteins and therefore accumulated in the blood.
E) Cholesterol was not transported into cells by facilitated diffusion and therefore accumulated in the blood.
Answer
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