Types of algae?
The member of cholophyceae are commenly called green algae. The plant body may be unicellular, colonial or filamentous. They are useually grass green due to dominance of pigment chorophyll a and b. The pigment are locolised in definite choroplasts. The choroplast may be discoid, plate-like, reticulate, cup-shaped, spiral or ribbon-shaped in differnt species. Most of the members one or more storage bodies called pyrenoids located in the chloroplast. Pyrenoids contain protein besides strach. Some algae may store food in the form of oil droplets. Green algae useually have a regit cell wall made od inner iayer of cellous and an outer layerr of pectose. Vegrtative reprodution useually takes place by fragemention of by formetion of differnt of spores. Asexual reprodution is by flagellated zoospores produced in zoosporengia. The sexual reprodution show considerable variation in types and formation of sex calls and t may be isogamous, anisogamous or oogamous. Some commely found green algae are : Chlamydomonas, volvox, ulothrix, spirogyea and chara.
Phaeophyceae
The member od phaeophyceae or brown algae are found primally in marine habitats. They show great varition in size and form. They range from simple branched, filamentous forms[ectocapus] to profusely branched forms as represent by kelps, which may reach a height of 100 meters. They posses chlophyll a, c, carotenoids and xanthophylls. They vary in colour form olive green to variation shades of brown depending upon the amount of the xanthophyll pigment, fucoxanthin present in them. Food is stroed as complex carbohydeates, which may be in the form of laminarin or mannitol. The vegetative cells have a cellous wall useually covered on the outside by a gelatinous algin. The protoplast contains in addition to plastids, a centrally located vacule and nucleus. The plant body is useually attached to the substratum by a holdfast, and has a atalk, the stripe and leaf like photosynthetic orgen-the frond. Vegetative reprodution may be place fragmention. Asexual reprodution in most brown algae is by biflagellated zoospores that are prar-shaped and have two unequal laterally attached flagella.
Sexual reprodution may be isogamous, anisogamous or oogamous. Union of gamets may take place in water or within the oogamous. The gamets are pyriform and bear two laterally attached flagella. The common forms are ecotocarpus, dictyoto, laminaria, sargassum and fusuc.
Rhodophyceae
The member of rhodophyceae are commonly called red algae because of predominance of red pigment, r-phycoerythrin in their body. Majority of the red algae are marine with greater concertration found in warmer areas. They occur in both well-lighted region close to the surface of water and also a great depth in ocean where relativly little light penetrates.
The red thalli of most of the red algae are multicellular. Sexual reproduction is oogamous and accompanied by complex post fertilisation developments. The common member are polysiphonia, porphyra, gracilaria and gelidium.
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