36. Plant Reproduction

Which two structures of a flower bear sporangia?

A generative cell and a tube cell originate when __________.

How many pollen grains can potentially result from one microsporocyte?

What is the purpose of synergids in an ovule?

In the process of pollination, pollen grains are transferred from the __________ to the __________.

Like gymnosperms, many grasses and angiosperm trees are wind-pollinated. To conserve energy, these angiosperms do not produce complete flowers (complete flowers have all four of the basic parts). Which basic part would most likely be missing from wind-pollinated angiosperm flowers?

How do most flowering plants avoid self-fertilization?

What is the underlying feature that allows plants to reproduce asexually?

In this type of asexual reproduction, seeds are produced even without the joining of sperm and eggs.

In an environment that is very stable, with reliable moisture and temperature, what type of reproduction would be most advantageous for a plant, and why?

Which statement below accurately describes the role of S-genes in plants?

Evaluate these statements about double fertilization. Select True or False for each sentence.T/FTwo zygotes are formed, but only one survives.T/FOne sperm fuses with an egg while the other sperm fuses with polar nuclei.T/FIt results in the formation of a diploid embryo and triploid endosperm.T/FBoth sperm involved in double fertilization form within the same pollen tube.

Double fertilization means thata. flowers must be pollinated twice to yield fruits and seeds.b. every egg must receive two sperm to produce an embryo.c. one sperm is needed to fertilize the egg, and a second sperm is needed to fertilize the polar nuclei.d. every sperm has two nuclei.

In angiosperms, each pollen grain produces two sperm. What do these sperm do? a. Each one fertilizes a separate egg cell. b. One fertilizes an egg, and the other is kept in reserve. c. Both fertilize a single egg cell. d. One fertilizes an egg, and the other fertilizes a cell that develops into stored food.

In angiosperms, are sperm and eggs produced by mitosis or meiosis? Which cells are spores? Which structures are gametophytes?