Assertion (A): | Pollen grains of flowering plants can be well preserved as fossils. |
Reason (R): | Hard outer layer of pollen grains is made up of most resistant, non degradable organic material called as sporopollenin. |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | Both (A) and (R) are false. |
Assertion (A): | At maturity, a typical angiospermic embryo sac is 7 celled 8-nucleated structure. |
Reason (R): | There is a characteristic distribution of the cells within the embryo sac of the angiosperms. |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | Both (A) and (R) are false. |
Assertion (A): | Cleistogamous flowers are invariably autogamous. |
Reason (R): | Cleistogamous flowers never expose their sex organs, so there is no chance of cross pollination in these flowers. |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | Both (A) and (R) are false. |
Assertion (A): | Some species of Asteraceae and grasses have evolved special mechanism to produce seeds without fertilisation called as apomixis. |
Reason (R): | Apomixis is a form of asexual reproduction that mimics sexual reproduction. |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | Both (A) and (R) are false. |
Assertion (A): | Cultivation of hybrids has tremendously increased the productivity. |
Reason (R): | If hybrids are made into apomicts, there is segregation of characters in the hybrid progeny.- |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | Both (A) and (R) are false. |
Assertion (A): | Pollen grains are not rich in nutrients. |
Reason (R): | Pollen consumption does not increase the performance of athletes and race horses. |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | Both (A) and (R) are false. |
Assertion (A): | Pollen grains represent the male gametophytes. |
Reason (R): | The cell wall of pollen grain is called sporoderm. |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | Both (A) and (R) are false. |
Assertion (A): | Wind pollinated flowers have large feathery stigma to trap pollen grains. |
Reason (R): | Wing pollination is common in plants like Amorphophallus and Yucca. |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | Both (A) and (R) are false. |
Assertion (A): | Geitonogamy involves a pollinating agent. |
Reason (R): | Genetically geitonogamy is similar to xenogamy |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | Both (A) and (R) are false. |