Question 1

Which of the following best describes the effect of solute concentration on water potential ($$\Psi) in $$plant cells?

Accepted Answer

Increasing solute concentration decreases water potential, causing water to move out of the cell.

Question 2

According to the equation $$\Psi = \Psi_s + \Psi_p$$, what does $$\Psi_s$$ represent?

Accepted Answer

$$\Psi_s is $$the solute potential, which is typically negative and reflects the effect of dissolved solutes.

Question 3

A plant cell is placed in a solution with a lower water potential than the cell. What will happen to the cell?

Accepted Answer

Water will move out of the cell, causing it to shrink.

Question 4

Which process is primarily responsible for the long-distance transport of water in the xylem?

Accepted Answer

Bulk flow driven by pressure differences

Question 5

The Cohesion-Tension Model explains water movement in plants by which of the following mechanisms?

Accepted Answer

Water is pulled up the xylem due to negative pressure created by transpiration at the leaf surface.

Question 6

Which of the following would most likely decrease the rate of transpiration in a plant?

Accepted Answer

High humidity in the surrounding air

Question 7

If a plant's xylem vessels collapse due to excessive negative pressure, what is the most likely consequence?

Accepted Answer

Water transport will cease, and the plant may wilt.

Question 8

Which equation correctly represents the relationship between water potential, solute potential, and pressure potential?

Accepted Answer

$$\Psi = \Psi_s + \Psi_p$$

Question 9

A plant is exposed to drought conditions. Which adaptation would help it maintain water transport?

Accepted Answer

Closing stomata to reduce water loss

Question 10

Which of the following best explains why water moves from the soil into the roots of a plant?

Accepted Answer

The water potential in the root cells is lower than in the soil.

Question 11

Which of the following is a direct result of transpiration in plants?

Accepted Answer

Negative pressure in the xylem that pulls water upward

Question 12

Which statement about bulk flow in the phloem is correct?

Accepted Answer

Bulk flow in the phloem is driven by positive pressure generated by loading of sugars at the source.

Question 13

Which of the following would most likely result in guttation in a plant?

Accepted Answer

Root pressure exceeding transpiration rate, usually in the early morning

Question 14

Which of the following is NOT a function of stomata in plant leaves?

Accepted Answer

Facilitating bulk flow in the xylem

Question 15

A plant cell with a pressure potential ($$\Psi_p) of 0.5 $$MPa and a solute potential ($$\Psi_s) of -0.7 $$MPa has a water potential ($$\Psi) of$$:

Accepted Answer

$$\Psi = -0.2$$ MPa

Question 16

Which of the following best describes the role of cohesion in the movement of water through the xylem?

Accepted Answer

Cohesion enables water molecules to form hydrogen bonds with each other, creating a continuous column of water.

Question 17

Which environmental factor would most likely cause stomata to close during the day?

Accepted Answer

High temperature and water stress

Question 18

Which of the following statements about the movement of water in plants is correct?

Accepted Answer

Water moves from regions of higher water potential to regions of lower water potential.

Question 19

Which adaptation would help a plant minimize water loss in a hot, dry environment?

Accepted Answer

Closing stomata during the hottest part of the day

Transpiration and Water Transport in Vascular Plants

Study Guide - Practice Questions