Which statement best describes the cellular function of metabolic
absorption?
a. Cells can produce proteins.
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b. Cells can secrete digestive
... [Show More] enzymes.
c. Cells can take in and use nutrients.
d. Cells can synthesize fats.
ANS: C
In metabolic absorption, all cells take in and use nutrients and other substances
from their surroundings. The remaining options are not inclusive in their
descriptions of cellular metabolic absorption.
PTS: 1 DIF: Cognitive Level: Remembering
2. Where is most of a cell’s genetic information, including RNA and DNA,
contained?
a. Mitochondria
b. Ribosome
c. Nucleolus
d. Lysosome
ANS: C
The nucleus contains the nucleolus, a small dense structure composed largely of
RNA, most of the cellular DNA, and the DNA-binding proteins, such as the
histones, which regulate its activity. The mitochondria are responsible for cellular
respiration and energy production.
Ribosomes’ chief function is to provide sites for cellular protein synthesis.
Lysosomes function as the intracellular digestive system.
PTS: 1 DIF: Cognitive Level: Remembering
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3. Which component of the cell produces hydrogen peroxide (H2O2) by using
oxygen to remove hydrogen atoms from specific substrates in an oxidative
reaction?
a. Lysosomes
b. Peroxisomes
c. Ribosomes
d. Endosome
ANS: B
Peroxisomes are so named because they usually contain enzymes that use oxygen
to remove hydrogen atoms from specific substrates in an oxidative reaction that
produces H2O2, which is a powerful oxidant and potentially destructive if it
accumulates or escapes from peroxisomes.
Ribosomes are RNA-protein complexes (nucleoproteins) that are synthesized in the
nucleolus and secreted into the cytoplasm through pores in the nuclear envelope
called nuclear pore complexes. Lysosomes are saclike structures that originate
from the Golgi complex and contain more than 40 digestive enzymes called
hydrolases, which catalyze bonds in proteins, lipids, nucleic acids, and
carbohydrates. An endosome is a vesical that has been pinched off from the
cellular membran [Show Less]