Bio 1108 Exam Practice Questions with
Correct Answers 2025-2026
If the two guard cells of a stoma decrease their concentration of potassium (K+) ions, what
will happen to the corresponding pore?
A. The pore will close, allowing the diffusion of water vapor out of the leaf.
B. The pore will close, preventing the diffusion of CO2 out of the leaf.
C. The pore will open, allowing for the diffusion of CO2 into the leaf.
D. The pore will open, allowing for the diffusion of water vapor into the leaf. -
CORRECT ANSWER The pore will close, preventing the diffusion of CO2 out of the leaf.
If water molecules (H2O) suddenly stopped forming hydrogen bonds with one another, how
would water transport in vascular plants change (if at all)?
A. It would remain the same, as H2O molecules also form oxygen bonds.
B. It would remain the same, as water transport only depends on osmosis.
C. It would stop, as water transport relies on H2O molecules being connected by hydrogen
bonds.
D. It would increase, as hydrogen bonds inhibit water transport. CORRECT ANSWER
It would stop, as water transport relies on H2O molecules being connected by hydrogen bo
nds.
Which of the following are produced by roots in order to increase surface area, allowing fo
r greater access to nutrients in the soil?
A. root hairs
B. root nodules
, C. root parenchyma
D. root Casparian strips CORRECT ANSWER root hairs
In a sunflower population, a mutation arises that results in vessels 4 times wider than wild-
type. The mutants will have water-
transport capacity, but will also be more susceptible to .
A. higher; cavitation from freezing
B. higher; cavitation from air leaks
C. higher; conduit collapse
D. lower; cavitation from freezing CORRECT ANSWER higher; cavitation from freezing
Roots elongate continuously in order to .
A. mine new regions of soil for minerals
B. act as a carbohydrate sink
C. obtain O2 CORRECT ANSWER mine new regions of soil for minerals
Root hairs develop .
A. on the entire root surface
B. before the cells elongate
C. after the cells elongate
D. on the root cap
E. all of these options are correct CORRECT ANSWER after the cells elongate
The veins of leaves are .
Correct Answers 2025-2026
If the two guard cells of a stoma decrease their concentration of potassium (K+) ions, what
will happen to the corresponding pore?
A. The pore will close, allowing the diffusion of water vapor out of the leaf.
B. The pore will close, preventing the diffusion of CO2 out of the leaf.
C. The pore will open, allowing for the diffusion of CO2 into the leaf.
D. The pore will open, allowing for the diffusion of water vapor into the leaf. -
CORRECT ANSWER The pore will close, preventing the diffusion of CO2 out of the leaf.
If water molecules (H2O) suddenly stopped forming hydrogen bonds with one another, how
would water transport in vascular plants change (if at all)?
A. It would remain the same, as H2O molecules also form oxygen bonds.
B. It would remain the same, as water transport only depends on osmosis.
C. It would stop, as water transport relies on H2O molecules being connected by hydrogen
bonds.
D. It would increase, as hydrogen bonds inhibit water transport. CORRECT ANSWER
It would stop, as water transport relies on H2O molecules being connected by hydrogen bo
nds.
Which of the following are produced by roots in order to increase surface area, allowing fo
r greater access to nutrients in the soil?
A. root hairs
B. root nodules
, C. root parenchyma
D. root Casparian strips CORRECT ANSWER root hairs
In a sunflower population, a mutation arises that results in vessels 4 times wider than wild-
type. The mutants will have water-
transport capacity, but will also be more susceptible to .
A. higher; cavitation from freezing
B. higher; cavitation from air leaks
C. higher; conduit collapse
D. lower; cavitation from freezing CORRECT ANSWER higher; cavitation from freezing
Roots elongate continuously in order to .
A. mine new regions of soil for minerals
B. act as a carbohydrate sink
C. obtain O2 CORRECT ANSWER mine new regions of soil for minerals
Root hairs develop .
A. on the entire root surface
B. before the cells elongate
C. after the cells elongate
D. on the root cap
E. all of these options are correct CORRECT ANSWER after the cells elongate
The veins of leaves are .
