51.

An example of a seed with endosperm, perisperm and caruncle is 

• Cotton

• coffee

• lily

• lily

Which one of the flowing pairs of plants structures has haploid number of chromosomes?

• Megaspore mother cell and antipodal cells

• Egg cell and antipodal cells

• Nucellus and antipodal cells

• Nucellus and antipodal cells

Unisexuality of flowers prevents

• autogamy, but not geitonogamy

• Both geitonogamy and xenogamy

• geitonogamy, but not xenogamy

• geitonogamy, but not xenogamy

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

• It helps in the entry of pollen tube into a synergid

• It prevents entry of more than one pollen tube into the embryo sac

• It brings about opening of the pollen tube

• It brings about opening of the pollen tube

Importance of day length in flowering of plants was first shown in 

• Lemna

• tobacco

• Cotton 

• Cotton 

Male gametes in angiosperms are formed by the division of

• microspore

• generative cell

• vegetative cell

• vegetative cell

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

• Microspore mother cell

• Male gamete

• Egg

• Egg

Parthenocarpic tomato fruits can be produced by

• Removing androecium of flowers before pollen grains are released

• Treating the plants with low concentrations of gibberellic acid and auxins

• Raising the plants from vernalized seeds

• Raising the plants from vernalized seeds

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

• anthers

• styles

• ovaries

• ovaries

Conifers differ from grasses in the

• production of seeds from ovules

• lack of xylem tracheids

• absence of pollen tube

• absence of pollen tube