Double fertilization, a characteristic of angiosperms, results in the formation of:
1. | diploid zygote due to syngamy and triploid primary endosperm cell due to triple fusion |
2. | triploid zygote due to triple fusion and diploid primary endosperm cell due to syngamy |
3. | diploid zygote due to syngamy and haploid primary endosperm cell as it is formed pre-fertilization |
4. | diploid zygote due to syngamy and diploid primary endosperm cell due to triple fusion |
Scutellum is:
1. | the cotyledon in seeds of the grass family |
2. | globular embryo of a dicot |
3. | persistent nucellus in a seed |
4. | undifferentiated sheath enclosing root cap in monocot seeds |
Seeds offer several advantages to angiosperms. Which of the following is not one?
1. | The process is more dependable |
2. | Better adaptive strategies for dispersal |
3. | Protection of the young embryo |
4. | Genetic uniformity |
Apomixis is:
I: | production of seeds without fertilization |
II: | production of fruits without fertilization |
III: | a form of asexual reproduction that mimics sexual reproduction |
1. Only I and II are correct
2. Only I is correct
3. Only III is correct
4. Only I and III are correct
What is the advantage of converting hybrids into apomicts for farmers?
1. | Can be easily produced year after year |
2. | Segregation of traits creates more diversity |
3. | A great reduction in cost |
4. | Overcoming inbreeding depression |
What guides the entry of the pollen tube though the micropyle into the embryo sac in the angiosperms?
1. | Antipodals | 2. | Filiform apparatus in synergids |
3. | The egg cell | 4. | Polar nuclei |
Tapetum:
1. | is the outermost layer in the wall of microsporangium |
2. | helps in the protection of the pollen grains |
3. | helps in dehiscence of anther |
4. | has cells that generally have more than one nucleus |
After pollination and fertilization, the ovule and the ovary, respectively, become:
1. | embryo and seed | 2. | seed and fruit |
3. | stigma and style | 4. | zygote and endosperm |
The number of cycles of mitotic cell divisions the megaspore goes through, before the embryo sac is fully formed is:
1. | 1 | 2. | 2 |
3. | 3 | 4. | 4 |
The correct description of the structure shown in the figure would be:
1. | Anatropous ovule; 1 – Nucellus; 2 – Chalaza; 3 – Raphe; 4 – Funiculus |
2. | Orthotropous ovule; 1 – Nucellus; 2 – Micropyle; 3 – Raphe; 4 – Funiculus |
3. | Anatropous ovule; 1 – Nucellus; 2 – Chalaza; 3 – Funiculus; 4 – Raphe |
4. | Anatropous ovule; 1 – Nucellus; 2 – Micropyle; 3 – Raphe; 4 – Funiculus |