What regulates the flow of water through the xylem?
a) the number of companion cells in the phloem
b) passive transport by the endodermis
c) the evaporation of water from the leaves
d) active transport by sieve-tube members
e) active transport by tracheid and vessel elements.
Ans: c) the evaporation of water from the leaves
You might also like to view...
Four of the five stages listed below are related by the
number of chromosomes present. Select the exception. a. sperm b. spermatogonia c. secondary spermatocyte d. early spermatids e. late spermatids
An RNA primer is synthesized by RNA primase
__________________ Indicate whether the statement is true or false.
Which of the following can be used to distinguish between a bacterial cell and an archael cell?
A. The presence of a plasma membrane B. The presence of a nucleus in the cell C. The presence of ribosomes in the cell D. The presence of peptidoglycan in the cell wall E. Answers A and C are correct F. Answers B and D are correct G. Answers A, B, and C are correct
Eukaryotic organisms speed up the process of DNA replication by
A. producing several sliding clamp complexes which provide more binding sites for DNA pol III. B. using multiple origins of replication on each chromosome. C. using DNA gyrase to unravel the double helix rather than DNA helicase. D. shortening the initiation phase.