Which of the Following Supports the Finding That Sugar Translocation

question 29

Multiple Choice

Which of the following supports the finding that sugar translocation in phloem is an active (energy-requiring) process?

• A) Sucrose occurs in higher concentrations in companion cells than in the mesophyll cells where it is produced.
• B) Movement of water occurs from xylem to phloem and back again.
• C) Strong pH differences exist between the cytoplasm of the companion cell and the mesophyll cell.
• D) ATPases are abundant in the plasma membranes of the mesophyll cells.