The water absorption rate of a plant's roots is greatly increased by
A. presence of many stomata only.
B. presence of root hairs only.
C. both association with mycorrhizal fungi and presence of root hairs.
D. association with mycorrhizal fungi only.
E. both presence of many stomata and root hairs.
Ans: C. both association with mycorrhizal fungi and presence of root hairs.
You might also like to view...
The primary reason steroid hormones usually act slowly is that _____
Fill in the blank(s) with the appropriate word(s).
A phosphate group is a compound containing phosphorus ____
a. and calcium attached to a base b. and sodium attached to a sugar c. chemically bonded to thymine d. chemically bonded to four oxygen molecules e. chemically bonded to three nitrogen molecules
A nucleus within an ascus undergoes meiosis, producing four haploid spores, which then undergo mitosis, producing eight haploid ascospores. These haploid ascospores contain a maximum of _____ different genetic types.
a) one b) two c) three d) four e) five
Phosphofructokinase (PFK) is an enzyme that converts fructose 6-phosphate to fructose 1,6-bisphosphate, by adding a phosphate group. This is the first committed step of the metabolic pathway of glycolysis, and thus it is very tightly regulated. AMP binds to PFK at a site distinct from the binding site for fructose 6-phosphate, and stimulates the formation of fructose 1,6-bisphosphate. ATP binds
to PFK at a site distinct from the binding site for fructose 6-phosphate, and inhibits the formation of fructose 1,6-bisphosphate. There are other regulators of this enzyme as well. What is the role of AMP in this example? A. Competitive inhibitor B. Noncompetitive inhibitor C. Allosteric inhibitor D. Allosteric activator E. Catalyst