Plant kingdom practice · Mixed difficulty

Option B (Cytotaxonomy) is correct because it specifically refers to classification based on cytological information, chromosome structure, and behavior.

Option B (Fucus does not show the same life-cycle pattern as most of the algae show) is correct because Fucus exhibits a diplontic life cycle, unlike most algae that have a haplontic or haplo-diplontic life cycle.

Option B (Female strobili) is correct because megasporophylls with ovules are found in female cones, also known as female strobili.

Option D (Pteridophytes) is correct because pteridophytes are vascular plants that reproduce via spores, not seeds.

Option D (Spore formation) is correct because meiosis in pteridophytes like Dryopteris occurs during spore formation within sporangia.

Option B (Presence of vessel elements and absence of archegonia) is correct because Gnetum possesses vessel elements, a characteristic of angiosperms, and lacks archegonia, unlike Cycas and Pinus.

Option B (Equisetum) is correct because Equisetum spores contain chloroplasts, allowing them to photosynthesize for a short period after dispersal.

Option A is correct because both the assertion and the reason are correct, and the reason correctly explains the assertion. Meiosis precedes embryo sac formation, resulting in haploid cells.

Option C (Humid, damp and shaded localities) is correct because bryophytes require moisture for reproduction and lack vascular tissues for efficient water transport, hence they thrive in such environments.

Option C (Angiosperms) is correct because angiosperms are characterized by having an eight-nucleated female gametophyte (embryo sac).

Option D (All of these) is correct because algae are found in diverse environments including fresh and marine water, moist stones, and moist soils and wood.

Option B (An independent sporophyte) is correct because Dryopteris (a fern) has a dominant and independent sporophyte, whereas Funaria (a moss) has a sporophyte dependent on the gametophyte.

Option D (Polysiphonia and Gelidium) is correct because Polysiphonia and Gelidium belong to class Rhodophyceae (red algae), not Phaeophyceae (brown algae).

Option A (Algae) is correct because phycology is the branch of botany that deals with the study of algae.

Option A (Red algae) is correct because carrageenan is a jelly-like substance obtained from certain species of marine red algae.

Option C (Both (1) and (2)) is correct because Selaginella exhibits both retention of the megaspore and heterospory, which are key characteristics associated with the evolution of the seed habit.

Option C (Companion cells) is correct because phloem in pteridophytes lacks companion cells, which are typically associated with sieve tubes in angiosperms.

Option D (Spermatophytes) is correct because microspores of spermatophytes are indeed called pollen grains, as spermatophytes are seed-bearing plants.

Option D (Fucus) is correct because Fucus, a brown alga, exhibits a diplontic life cycle, similar to angiosperms.

Option A (A-2n; B-n) is correct because the sporophytic generation is diploid (2n) and the gametophytic generation is haploid (n).

Option C (2) is correct because statements (b) and (c) are correct. Linnaeus did not propose classification based on evolutionary relationships, and mosses have a haplodiplontic life cycle.

Option B (Chemotaxy) is correct because sperm movement towards the archegonium in ferns is guided by chemical signals.

Option B (If both assertion and reason are correct but reason is not a correct explanation of the assertion) is correct because both the assertion and reason are true, but the reason doesn't explain why liverworts fail to spread through fragmentation.

Option A (Cool, damp and shady places) is correct because pteridophytes require these conditions for the gametophyte to grow and for fertilization to occur.

Option D (Angiosperm) is correct because angiosperms have the most reduced gametophyte stage compared to other plant groups.

Option B (Anemophilous) is correct because Pinus relies on wind for pollination, which is known as anemophily.

Option C (Acetebularia) is correct because Acetabularia is a genus of green algae known for being a large, single-celled organism, making it the largest unicellular algae.

Option B (54) is correct because the endosperm of gymnosperms is formed before fertilization and is therefore haploid (n). Since the diploid number (2n) is 36, the haploid number (n) is 18. The endosperm is the result of the fusion of the egg (n) and the two polar nuclei (n+n), so it is triploid (3n). Therefore, the number of chromosomes in the endosperm is 3 * 18 = 54.

Option D (Selaginella and Salvinia) is correct because both Selaginella (a pteridophyte) and Salvinia (an aquatic fern) produce two types of spores (microspores and megaspores), making them heterosporous.

Option C (Flower) is correct because flowers are the reproductive structures in angiosperms where pollen grains and ovules are produced.