I: | Protonema is a gametophyte stage that is creeping, green, branched and frequently filamentous. |
II: | Leafy stage bears sex organs and is attached to the soil through multicellular and branched rhizoids. |
III: | Sex organs are produced at the apex of the leafy shoot. |
IV: | They have an elaborate mechanism of spore dispersal. |
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R):
Assertion (A): | Heterospory in some pteridophytes paved the way for the evolution of seeds in higher plants. |
Reason (R): | The megaspores and microspores in heterosporous ferns give rise to female and male gametophytes respectively. |
In the light of the above statements choose the correct answer from the options given below:
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. | (A) is False but (R) is True. |
I. | Sporophytic generation is represented only by the one-celled zygote. |
II. | Meiosis in zygote results in the formation of haploid gametes. |
III. | The dominant photosynthetic stage is the free living gametophyte |
1. | Only I is correct |
2. | Only I and III are correct |
3. | Only II is correct |
4. | I, II and III are correct |
1. | Red algae | 2. | Bryophytes |
3. | Pteridophytes | 4. | Gymnosperms |
1. Red algae | 2. Bryophytes |
3. Pteridophytes | 4. Gymnosperms |
Character | Pinus | Cycas | |
1. | Root symbiotic association | Mycorrhiza | Cynobacteria |
2. | Stem | Branched | Unbranched |
3. | Reproductive parts | Dioecious | Monoecious |
4. | Scale leaves | Fall off as branches mature | Persistent, protective |
Consider the following statements:
I: | Pteridophytes are the first terrestrial plants to possess vascular bundles. |
II: | Main plant body in pteridophytes is sporophyte which is differentiated into true stem and leaves. |
III: | Genera like Selaginella and Salvinia are heterosporous. |
Which of the above statements are true?
1. | I and II only | 2. | I and III only |
3. | II and III only | 4. | I, II and III |