Exam 27: Regulating Growth and Development: the Plant Hormones

Salicylic acid regulates thermogenesis in members of the arum family.

In studies of leaf senescence, when an excised leaf containing radioactive amino acids is spotted with a kinetin-containing solution, the spot:

The transport of auxin can be nonpolar as well as polar.

Based on the results of experiments with cultured mesophyll cells of Zinnia elegans, you would predict that if brassinosteroids were excluded from the culture medium, no tracheary elements would be formed.

______ activates the biosynthesis of ________, which then activates the genes that encode protease inhibitors.

An excised leaf floated in a kinetin solution will remain green longer than a leaf floated in water.

Cell wall extensibility, and thus cell expansion, is increased by ______ but decreased by ______.

Rice plants grow rapidly and become spindly due to the presence of gibberellic acid produced by a fungus.

In roots of Arabidopsis, cytokinin ______ the initiation of lateral roots by preventing the establishment of a(n) ______ gradient.

Which of the following statements concerning endogenous brassinosteroids is FALSE?

Polar transport is ______ in stems, _______in leaves, and ______ in roots.

Gibberellins promote fruit development in some species in which auxin does not.

Which of the following statements about 2,4-D is FALSE?

In Arabidopsis, the ethylene receptor is located in the plasma membrane.

In climacteric fruits, there is a large increase in cellular respiration during ripening.

In apical dominance, the apical bud:

The weed killer 2,4-D is a synthetic cytokinin.

In the acid-growth hypothesis of cell wall extensibility, which of the following events occurs FIRST?

Which of the following is a phenolic compound with a structure similar to aspirin?

Plant hormones usually act alone and only occasionally "cross-talk."