Algae vegetative structure
Carpogonia are produced at the tip of special branches carpogonial branchestypically flask-shaped with long, thin neck called trichogyne.
The flagellated reproductive cells show that Fritschiella is in fact closely related to the chlorophyte green algae, rather than to the charophyte green algae that gave rise to land plants. Asexual reproduction -In asexual reproduction only one parent is involved. Furthermore, groups like the apicomplexans are also parasites derived from ancestors that possessed plastids, but are not included in any group traditionally seen as algae. The only groups to exhibit three-dimensional multicellular thalli are the reds and browns , and some chlorophytes. In algae, as in plants, haploid cells in this stage are called gametophytes because they produce gametes. The zygote takes rest and during favourable condition germinates into a new plant, which bears asexual spores again. Autogamy: In this process the fusing gametes are developed from the same mother cell and after fusion they form zygote. Yes, that is what algae are, microscopic plants! Usually develop on the rhizoids of Chara are called bulbils. It is of three types: i.
Carposporophytes always live on the female gametophyte and receive nutrients from the gametophyte. Usually the protoplast of each cell converts in a single akinete.
The algae that grow on the surface of the soil are known as saprophytes. In addition to these methods, several perennating bodies also develop which face the adverse conditions. Asexual reproduction -In asexual reproduction only one parent is involved. Thus true branches arise as lateral outgrowths of the main filament. Hence, the land plants are referred to as the Embryophytes. Some red algae produce monospores walled, nonflagellate, spherical cells that are carried by water currents and upon germination produce a new organism. Each and every spore germinates into a new plant. While algae have been traditionally regarded as simple plants, they actually belong to more than one domain, including both Eukaryota and Bacteria see Blue-green algae , as well as more that one kingdom, including plants and protists. Consequently, the new valves are generally somewhat smaller than the originals, so after many successive generations, most of the cells in the growing population are smaller than their parents. Palmelloid: In this type the non- motile cells remain embedded in an amorphous gelatinous or mucilaginous matrix.
Certain cells of the tetrasporophyte undergo meiosis to produce tetraspores, and the cycle is repeated. Example - Chlorella image The individual cells also exhibit a wide variety of different coverings.
Peat: Comparative structure of the gas-vacuoles of blue-green algae. They are found in Rhodophyceae. External morphology :-The body of a typical brown algae is divided into three parts :- Holdfast :- This is a basal root like structure by which algae is attached strongly to the rocks.
Google Scholar ——: Fine structure of Mycota. The algae growing in the desert soil may be typified as endedaphic living in soil , epidaphic living on the soil surface , hypolithic growing on the lower surface of the stones on soil , chasmolithic living in rock fissures and endolithic algae which are rock penetrating. Juniper: Microfibrillar structure in the fungal portions of the lichen Xanthoria parietina L. The fertilisation takes place within oogonium. All the vital function of life are performed by the single cell occasionally the term acellular -used. Sexual reproduction :- sexual reproduction takes place by the formation of flagellate gametes that are formed inside gametangia. Vaucheria, Caulerpa Uniaxial type :-The outer sheathing layer of the axis is always one celled in thickness eg.
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