Reproduction in Porphyra The life istory of Porphyra involves alternation of generation between macroscopic, foliose gametophytic phase and microscopic, filamentous sporophytic phase. During favourable condiions the spermaia fuse with the tip of the carpogonia. When the female and male nuclei fuse together they form diploid cells and the carposporophyte. These carpoonial cells divide many times and they eventually form diploid carpospores. The carpospores first undergo a cruciate division, followed by a parallel division and finally a cruciate division of each segment. The carpospores grow into division of each segment. The carpospores grow into unipolar sporelings. These sporelings produce the conchocelis phase. he conchocelis phase is microscopic branching filament. Conchocelic plants have a filamentius form. The longitudinal division of the 3-sides apical cell spread from near the tip backward and form a monostromatic thallus. The thallus has serrulated margin with spinulose processes. The cochocelis filaments can reproduce themselves by releasing monospores that grow backwad into a conchocelis form. The conchocelis phase can also produce carposporangia by meiosis. The conchospores grow into bipolar sporelings, which eventually groe into a adult porphyra. The thallus has serrulated margin with spinulose processes. The thallus is surounded by a hick mucilage. As the alga matures the fronds become pale along the margin. The thallus produces three type of reproductive bodies monospore, spermatia and carpospores. Monospores are nearly spherical in shape. The thallus is monoecious. The fertile zone developed from the apex and marginal side and later on extneded inward to the interior of the thallus. The spermatangia produce spermatia and the carposporangia produces carpospores. Both kind of spores are haploid in number.. The spermatia are circular in shape. The fertilized carposporangia mother cell under go several divisions to form carpspores. The carpospores give ries to conchocelis phase by unipolar germination. This sporpophytic phase is a shellboring phase. The conchoelis phase shows filamentos naure. the filaments were narrow and the content is scanty. Terminal portion of the perpera filamentouss have a erminal conchosporangium.. This flast shaped structure lebraed conchospores. the conchosporangial mother cell undego meiosis before the formaion of conchospores. The conchospores settles on rocky substratum and during favourable conditions germinate to ive rise to the gametophtic thallus by bipolar germination. The alga attaches itself to the substratum by means of holdfast wich is often disc shaped. Thus, the life cycle of Porphyra is characterised by 2 phasses a leafy thallus, the haploid gametophyte and a filamentous conchocelis the diploid sporophyte Asexual cycle of Porphyra is much simpler that the sexual cycle. The adult Porphyra releases aplanospores nonflagellated spores, in packets of 8 or 16. The aplanospores grow into bipolar sporelings and eventually into adult Porphyra thalli. The asexual cycle lacks the fusion of sperm and egg cycle. Youn Porphyra reporduce asexually by aplanospores. Asexal reproduction by aplanospores is common in Porphyra species.