Sexual Reproduction in Flowering Plants

Which one of the following pairs of plant structures has haploid number of chromosomes?

1. Nucellus and antipodal cells
2. Egg nucleus and secondary nucleus
3. Megaspore mother cell and antipodal cells
4. Egg cell and antipodal cells

What does the filiform apparatus do at the entrance into ovule?

1. It brings about opening of the pollen tube.
2. It guides pollen tube from a synergid to egg.
3. It helps in the entry of pollen tube into a synergid.
4. It prevents entry of more than one pollen tube into the embryo sac.

Unisexuality of flowers prevents

1. geitonogamy, but not xenogamy
2. autogamy and geitonogamy
3. autogamy, but not geitonogamy
4. both geitonogamy and xenogamy

Which one of the following is resistant to enzyme action?

1. Pollen exine
2. Leaf cuticle
3. Cork
4. Wood fibre

Male gametes in angiosperms are formed by the division of

1. generative cell
2. vegetative cell
3. microspore mother cell
4. microspore

Which one of the following is surrounded by a callose wall?

1. Male gamete
2. Egg
3. Pollen grain
4. Microspore mother cell

Long filamentous threads protruding at the end of a young cob of maize are

1. hairs
2. anthers
3. styles
4. ovaries

In a cereal grain the single cotyledon of embryo is represented by

1. coleoptile
2. coleorhiza
3. scutellum
4. prophyll.

The arrangement of the nuclei in a normal embryo sac in the dicot plants is

1. 3 + 3 + 2
2. 2 + 4 + 2
3. 3 + 2 + 3
4. 2 + 3 + 3

In a type of apomixis known as adventive embryony, embryos develop directly from the

1. nucellus or integuments
2. zygote
3. synergids or antipodals in an embryo sac
4. accessory embryo sacs in the ovule.