Wind pollinated flowers are
(1) small, brightly coloured, producing large number of pollen grains
(2) small, producing large number of dry pollen grains
(3) large, producing abundant nectar and pollen
(4) small, producing nectar and dry pollen
Which one of the following pairs of plant strucutre has haploid number of chromosomes?
(1) Megaspore mother cell and antipodal cells
(2) Egg cell and antipodal cells
(3) Nucellus and antipodal cells
(4) Egg nucleus and secondary nucleus
Endosperm is consumed by developing embryo in the seed of
What does the filiform apparatus do at the entrance into ovule?
(1) It helps in the entry of pollen tube into a synergid
(2) It prevents entry of more than one pollen tube into the embryo sac
(3) It brings about opening of the pollen tube
(4) It guides pollen tube from a synergid to egg
Which one of the following is resistant to enzyme action?
(2) Wood fibre
(3) Pollen exine
(4) Leaf cuticle
Male gametes in angiosperms are formed by the division of:
(2) generative cell
(3) vegetative cell
(4) microspore mother cell
Which one of the following is surrounded by a callose wall?
(1) Microspore mother cell
(2) Male gemete
(4) Pollen grain
What would be the number of chromosomes in the cells of the aleurone layer in a plant species with 8 chromosomes in it synergids ?
Parthenocarpic tomato fruits can be produced by :
(1) removing androecium of flowers before pollen grains are released
(2) treating the plants with low concentrations of gibberellic acid and auxins
(3) raising the plants from vernalized seeds
(4) treating the plants with phenylmercuric acetate.
Long filamentous threads protruding at the end of a young cob of maize are :