Double fertilization is exhibited by
1. Angiosperms
2. Gymnosperm
3. Algae
4. Bryophytes
| 1. | Double fertilization results in two identical zygotes, providing redundancy and ensuring seed development even if one fails. |
| 2. | In double fertilization, both sperm cells fuse with the egg cell, enhancing genetic diversity in the resulting seed. |
| 3. | The two fertilization events form twin embryos that develop independently within the same seed coat. |
| 4. | One sperm fertilizes the egg cell to form a diploid zygote, while the other fuses with two polar nuclei to form a triploid endosperm, which nourishes the developing embryo. |
| List-I (Process) |
List-II (Description) |
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| A. | Microsporogenesis | I. | Formation of microspores from microspore mother cell |
| B. | Megasporogenesis | II. | Formation of functional megaspore from MMC |
| C. | Syngamy | III. | Fusion of male gamete with egg |
| D. | Triple fusion | IV. | Fusion of male gamete with central cell nuclei |
| 1. | A-I, B-II, C-III, D-IV | 2. | A-II, B-I, C-IV, D-III |
| 3. | A-I, B-III, C-II, D-IV | 4. | A-IV, B-II, C-I, D-III |
Which one of the following generates new genetic combinations leading to variations?
1. vegetative reproduction
2. parthenogenesis
3. Sexual reproduction
4. Nucellar polyembryony
Which structures of a seed are formed in flowering plants after syngamy and triple fusion respectively?
1. Endosperm and cotyledons
2. Embryo and endosperm
3. Cotyledons and testa
4. Embryo and seed coat
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 other(s) degenerate(s) in the synergid |
| 3. | All fuse with the egg |
| 4. | One fuses with the egg and other(s) fuse(s) with the synergid nucleus |
| 1. | It fuses with the zygote to form the embryo. |
| 2. | It provides genetic material for embryo formation. |
| 3. | It gives rise to the triploid endosperm that nourishes the developing embryo. |
| 4. | It protects the embryo from desiccation during seed development. |
| Statement A: | The primary endosperm nucleus (PEN) is formed by the fusion of one male gamete with two polar nuclei. |
| Statement B: | The endosperm provides nutrition to the developing embryo and in some plants persists in mature seeds. |
| 1. | Statement A is correct but Statement B is incorrect |
| 2. | Both Statement A and Statement B are incorrect |
| 3. | Statement A is incorrect but Statement B is correct |
| 4. | Both Statement A and Statement B are correct |