NEET 2015 Botany Bryophytes and Pteridophytes Multiple Correct Question

Statement Analysis:

1. Statement (i): Mosses and lichens are the first organisms to colonise a bare rock.

   • Correct. Mosses (a group of bryophytes) and lichens (a symbiotic association between fungi and algae) are often the pioneer species in primary succession, establishing themselves on bare rock where no soil exists.

2. Statement (ii): Selaginella is a homosporous pteridophyte.

   • Incorrect. Selaginella is a heterosporous pteridophyte, meaning it produces two types of spores: microspores (male) and megaspores (female). This is a vital distinction as homosporous plants produce only one type of spore.

3. Statement (iii): Coralloid roots in Cycas have VAM.

   • Incorrect. Coralloid roots in Cycas are associated with cyanobacteria, not vesicular-arbuscular mycorrhizae (VAM). They help in nitrogen fixation rather than the nutrient exchange characteristic of VAM.

4. Statement (iv): Main plant body in bryophytes is gametophytic, whereas in pteridophytes it is sporophytic.

   • Correct. In bryophytes, the dominant phase of the life cycle is the gametophyte, which is the green, photosynthetic plant we typically recognize. In contrast, pteridophytes (ferns and their relatives) have a dominant sporophyte phase, which is the larger structure that produces spores.

5. Statement (v): In gymnosperms, male and female gametophytes are present within sporangia located on sporophyte.

   • Correct. In gymnosperms, the male gametophyte (pollen) and female gametophyte (within the ovule) develop within sporangia on the sporophyte generation. This structure is critical for reproduction in gymnosperms.

Correct Answer:

• Based on the analysis above, the correct option is B) (i), (iv), and (v).

Explanation of Incorrect Options:

• Option A: (i), (iii), and (iv)

  • Incorrect because statement (iii) is false; coralloid roots do not have VAM.

• Option C: (ii), (iii), and (v)

  • Incorrect since both statements (ii) and (iii) are false. Selaginella is heterosporous, and coralloid roots do not involve VAM.

• Option D: (i), (iii), and (v)

  • Incorrect because statement (iii) is false, as mentioned above.

Summary:

The correct answer is B) (i), (iv), and (v) because all these statements are true according to our analysis. Understanding the differences in plant reproductive structures and life cycles is essential for grasping the complexities of plant biology, particularly in the context of bryophytes, pteridophytes, and gymnosperms.