Explain briefly the following terms with suitable examples:- (i) protonema (ii) antheridium (iii) archegonium (iv) diplontic (v) sporophyll (vi) isogamy
(i) Protonema -It is the primary degree withinside the lifestyles cycle of a moss, growing at once from the spore. It is composed of creeping, green, branched, and frequently filamentous structures. (ii) Antheridium - It is the male intercourse organ found in bryophytes and pteridophytes and is surrounded through a jacket of sterile cells. It encloses the sperm mom cells, which provide upward push to the male gametes. (iii) Archegonium - It is the woman intercourse organ found in bryophytes, pteridophytes, and gymnosperms. In bryophytes and pteridophytes, it typically has a swollen venter and a tubular neck, and incorporates the woman gamete referred to as the egg. (iv) Diplontic - It is the time period used for the lifestyles cycles of seed-bearing plants (gymnosperms and angiosperms). In those plants, the diploid sporophyte is dominant, photosynthetic, and independent. The gametophyte is represented with the aid of using a single-celled (or a few-celled) structure. (v) Sporophyll - In pteridophytes, the sporophytic plant frame bears sporangia. These sporangia are subtended through leaf-like appendages referred to as sporophylls. In gymnosperms, microsporophylls and megasporophylls are found. These undergo microspores and megaspores respectively. (vi) Isogamy -It is a sort of sexual duplicate regarding the fusion of morphologically-comparable gametes. This means that the gametes are of the identical size, however carry out specific functions. This kind of replica is commonly discovered inSpirogyra.
