R
U
G
R
TO
TU
, U
R
U
G
R
TO
TU
, U
R
U
G
R
TO
TU
, kjhgfds
d. cAMP
ANS: D
Feedback
A cAMP is the second messenger; aDNA is not.
B cAMP is the second messenger; mRNA is not.
C cAMP is the second messenger; dGMP is not.
D Correct. cAMP transmits information to the intracellular organelles when
activated by surface receptors on the plasma membrane.
TU
DIF: Recall REF: p. 3 OBJ: 3
4. Which cellular component facilitates protein synthesis?
a. Ribosomes
b. Lysosomes
TO
c. Mitochondria
d. Plasmalemma ANS: A
Feedback
A Correct. Ribosomes synthesize protein.
B Lysosomes facilitate the breakdown of intracellular and extracellular substances.
R
C Mitochondria generate energy.
D The plasmalemma provides a protective barrier and regulates the transport of
substances to and from the cell.
G
5. Which organelle produces microtubules?
a. Nucleus
U
b. Centriole
c. Golgi apparatus
d. Endoplasmic reticulum ANS: B
R
Feedback
A Centrioles generate microtubules; the nucleus does not.
U
B Correct. Centrioles produce microtubules.
C Centrioles generate microtubules; the Golgi apparatus does not.
D Centrioles generate microtubules; the endoplasmic reticulum does not.
DIF: Recall REF: p. 3 OBJ: 1
6. Which phase of the cell cycle is characterized as the initial resting stage?