Quiz_Ptridophyta December 8, 2024 by Vijay Wardhan 1. The megasporangia of Selaginella can be identified due to their: Size and colour Size None of the above Large size, four lobed structure and whitish colour Explanation:Megasporangia in Selaginella are identifiable by their large size, four-lobed structure, and whitish color. These characteristics distinguish them from microsporangia, which are smaller and different in color. 2. Amphiphloeic siphonostele develops in rhizome of: Lycopodium Marsilea Equisetum Selaginella Explanation:An amphiphloeic siphonostele, which has phloem on both the inner and outer sides of the xylem, develops in the rhizome of Marsilea. This type of stele is characteristic of certain ferns. 3. Male gametes in Dryopteris are: Multiciliate Sickle-shaped and biciliate Sickle-shaped and multiciliate Multiciliate and spirally coiled Explanation:Male gametes in Dryopteris are multiciliate and spirally coiled. The multiple flagella enable them to swim towards the archegonia for fertilization. 4. The fern plant is: Heterosporous Homosporous None of the above May be heterosporous or homosporous Explanation:Most ferns are homosporous, meaning they produce only one type of spore that develops into a bisexual gametophyte. This is in contrast to heterosporous plants, which produce two distinct types of spores (microspores and megaspores). 5. The ferns are usually found: In marshy place Near marshy places In dry climate In shady, cool and moist places Explanation:Ferns thrive in environments that provide shade, cool temperatures, and moisture. These conditions are ideal for their growth and reproduction, as they require a moist habitat for the development of their gametophytes. 6. Sporophyte of fern is: Independent on the gametophyte even from the beginning Dependent on the gametophyte in the beginning only All of the above are wrong Dependent upon the gametophyte always Explanation:The sporophyte of a fern is initially dependent on the gametophyte for nutrition and support. Once it matures, it becomes an independent plant capable of photosynthesis and further growth. 7. The stem-like character of rhizophore of Selaginella is: Absence of root cap Exogenous origin Both (a) and (b) are correct Absence of nodes Explanation:Rhizophores in Selaginella exhibit stem-like characteristics such as exogenous origin (growing from the surface) and the absence of a root cap. These features distinguish them from true roots. 8. Cyathia is characterized by: Leptosporangiate nature Tree habit All of the above Megaphyllous character with naked sori on sporophylls Explanation:Cyathia is characterized by its tree habit, leptosporangiate nature, and megaphyllous leaves with naked sori on sporophylls. These features are typical of certain advanced ferns. 9. A number of short stalked sporangia attached with placenta and covered by indusium is called: Sorus Ramenta Cone Sporophyll Explanation:A sorus is a cluster of sporangia (structures that produce spores) found on the underside of fern fronds. These clusters are often covered by a protective layer called the indusium. 10. In pteridophytes, meiosis occurs at the stage of: Gamete formation Spore formation Any of the above is possible Prothallus formation Explanation:In pteridophytes, meiosis occurs during spore formation. This process reduces the chromosome number by half, resulting in haploid spores that will develop into gametophytes. Loading …
