Which of the following would be least likely to affect osmosis in plants?
c. receptor proteins in the membrane
Active transport involves all of the following except the
a. slow movement through the lipid bilayer of a membrane.
Like many plant processes, transport of various materials in plants at the cellular level requires all of the following except
e. xylem membranes.
Which of the following is not a function of the plasma membrane proton pump?
d. equalizes the charge on each side of a membrane
The amount and direction of movement of water in plants can always be predicted by measuring which of the following?
e. water potential ( )
If P = 0.3 MPa and S = -0.45 MPa, the resulting is
c. -0.15 MPa.
The value for in root tissue was found to be -0.15 MPa. If you take the root tissue and place it in a 0.1 M solution of sucrose ( = -0.23), net water flow would
a. be from the tissue into the sucrose solution.
Compared to a cell with few aquaporins in its membrane, a cell containing many aquaporins will
a. have a faster rate of osmosis.
Some botanists argue that the entire plant should be considered as a single unit rather than a composite of many individual cells. Which of the following cellular structures cannot be used to support this view?
Which of the following statements is false about bulk flow?
d. It depends on the force of gravity on a column of water.
Which of the following statements about xylem is incorrect?
c. It transports mainly sugars and amino acids.
Which of the following would likely not contribute to the surface area available for water absorption from the soil by a plant root system?
Root hairs are most important to a plant because they
c. increase the surface area for absorption.
What is the role of proton pumps in root hair cells?
b. acquire minerals from the soil
In plant roots, the Casparian strip is correctly described by which of the following?
d. It ensures that all water and dissolved substances must pass through a cell before entering the stele.
Pine seedlings grown in sterile potting soil grow much slower than seedlings grown in soil from the area where the seeds were collected. This is most likely because
e. both B and D
A water molecule could move all the way through a plant from soil to root to leaf to air and pass through a living cell only once. This living cell would be a part of which structure?
d. the endodermis
The following factors may sometimes play a role in the movement of sap through xylem. Which one depends on the direct expenditure of ATP by the plant?
d. concentration of ions in the symplast
What is the main cause of guttation in plants?
a. root pressure
One is most likely to see guttation in small plants when the
b. root pressure exceeds transpiration pull.