Which of the following does not require expenditure of energy?
A. accumulation of ions inside a cell
B. transport against a concentration gradient
C. flow of sucrose and other carbohydrates once inside the sieve tubes
D. the loading and unloading of carbohydrates from the sieve tubes
E. opening or closing stomata
C. flow of sucrose and other carbohydrates once inside the sieve tubes
Once inside the sieve tubes, water flows via osmosis from xylem into the phloem. This raises the pressure within the tubes and this pressure moves the material through the phloem.
You might also like to view...
How many mass extinctions have occurred over all of geologic history?
a. one b. two c. three d. four e. five
Tendons and ligaments are composed of ________.
Fill in the blank(s) with the appropriate word(s).
If a tree 50 meters (m) high has 30,000 leaves, the surface area of the leaves is 300 m2, and the amount of ground covered by the tree's canopy is 75 m2. The leaf area index (LAI) is
A) 4. B) 6. C) 100. D) 400.
The genome of phiX174 is ________.
A. double-stranded RNA B. single-stranded RNA C. single-stranded DNA D. double-stranded DNA