Pollen grains are produced by
a.male reproductive structures.
b. flowers.
c. female reproductive structures.
d. ovules.

Which of the following is the only tissue that produces new plant cells?
a. phloem
b. ground tissue
c. xylem
d. meristematic tissue

A period of dormancy can allow seeds to germinate
a. under poor conditions.
b. without water.
c. under ideal conditions.
d. in extreme
temperatures.

What might a thin tree ring indicate?
a. decreased production of phloem
b. xylem production in winter
c. a year of drought
d. increased production of xylem

Cytokinins differ from auxins in that cytokinins
a. cause seeds to remain dormant.
b. inhibit lateral bud growth.
c. cause leaves to fall.
d. inhibit elongation of cells