What is the fate of the male gametes discharged in the synergid?
1. | One fuses with the egg and the other fuses with central cell nuclei |
2. | One fuses with the egg and the other(s) degenerate(s) in the synergid |
3. | All fuse with the egg |
4. | One fuses with the egg and the other(s) fuse(s) with a synergid nucleus |
Double fertilization is different from single fertilization because of the presence of
1. Syngamy
2. Seed
3. Triple fusion
4. Megaspore and micropore
The entry of pollen tube into the embryosac takes place due to the chemo-attractant secreted by
1. Tapetum
2. Oosphere
3. Filiform apparatus
4. Antipodal
Double fertilization is exhibited by:
1. Algae
2. Fungi
3. Angiosperms
4. Gymnosperms
1. | Fusion of two male gametes of a pollen tube with two different eggs |
2. | Fusion of one male gamete with two polar nuclei |
3. | Fusion of two male gametes with one egg |
4. | Syngamy and triple fusion |
In double fertilization total number of male nuclei and total number of female nuclei involved are:
(1) 3, 2 respectively
(2) 2, 3 respectively
(3) 2, 2 respectively
(4) 3, 3 respectively
Double fertilization involves
(1) fertilization of the egg by two male gametes
(2) fertilization of two eggs in the same embryo sac by two sperms brought by one pollen tube
(3) fertilization of the egg and the central cell by two sperms brought by different pollen tubes
(4) fertilization of the egg and the central cell by two sperms brought by the same pollen tube.
After double fertilizaton, a mature ovule has
(1) 1 diploid and 1 haploid cell
(2) 1 diploid and 1 triploid cell
(3) 2 haploid and 1 triploid cell
(4) 1 haploid and 1 triploid cell
The central cell in the embryo sac, after triple fusion, becomes:
(1) Primary endosperm cell
(2) Endosperm
(3) Embryo
(4) Zygote
Which of the following statements is false about filiform apparatus?
1. | The synergids have special cellular thickenings at the micropylar tip called filiform apparatus |
2. | It plays an important role in guiding the pollen tubes into the synergid |
3. | Both (1) and (2) |
4. | Pollen tube stimulates the formation of filiform apparatus |