Question 7
Original source text (the original panel preserves all diagram labels, tables and choices):
You are conducting a laboratory experiment on a particular group of cells that
have been supplied with oxygen. After a certain period, you decide to cut off the
oxygen supply to these cells. Following this, you observe that the amount of
amino acid absorbed by the cells drops drastically.
Based on these observations, which of the following statements BEST explains
why the amount of amino acid absorbed by the cells decreased so significantly
when the oxygen was cut off?
A. Amino acids cannot be absorbed by the cells when oxygen is absent.
B. Amino acids are absorbed by the cells mainly through active transport.
C. Amino acids require oxygen for digestion of protein molecules by enzymes.
D. Amino acids are absorbed by the cells mainly by muscular contractions of
the cells.
You are conducting a laboratory experiment on a particular group of cells that
have been supplied with oxygen. After a certain period, you decide to cut off the
oxygen supply to these cells. Following this, you observe that the amount of
amino acid absorbed by the cells drops drastically.
Based on these observations, which of the following statements BEST explains
why the amount of amino acid absorbed by the cells decreased so significantly
when the oxygen was cut off?
A. Amino acids cannot be absorbed by the cells when oxygen is absent.
B. Amino acids are absorbed by the cells mainly through active transport.
C. Amino acids require oxygen for digestion of protein molecules by enzymes.
D. Amino acids are absorbed by the cells mainly by muscular contractions of
the cells.