Tag: algae
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Soil as Ecological Factor
Introduction Soil consists of weathered layer of Earth’s crust with products of decay of living organisms intermingled. In soil, thus, abiotic & biotic components are intimate. Soil is considered to be chief organizing centre for land ecosystems. Pedosphere: Outermost layer of earth that is composed of soil & subject to its formation. Pedogenesis: Process of…
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Xanthophyceae (Yellow Green Algae)
General characteristics of Xanthophyceae Members of Xanthophyceae are commonly fresh water (Tribonema) and most of them are free floating. Plant body is unicellular (Heterochloris) or multicellular. The multicellular bodies also exhibit various forms like: Palmelloid (Chlorogloea), dendroid (Mischococcus), coccoid (Chlorobotrys), rhizopodial (Stipitococcus). Cells are eukaryotic with silica and pectin in cell wall. Chief pigment are…
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SOIL – Class 7
Soil is the upper most part of the surface of land. It contains many particles in it. FORMATION OF SOIL Weathering is a process in which huge rocks are broken down by the action of heat, wind, water and other natural and anthropogenic way to form small particles called soil. Formation of soil is a…
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Ectocarpus
Systematic position Class- Phaeophyceae Order- Ectocarpales Family- Ectocarpaceae Genus – Ectocarpus Occurrence Plant body is cosmopolitan in distribution mainly in colder areas of temperate and polar region and along Atlantic coast About 16 species are reported in India. Majority of species are lithophytes (attached on rocks.) Some are marine algae few are fresh water forms.…
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PHAEOPHYCEAE (Brown Algae)
Plant body is colonial, motile, non-motile, unbranched, filamentous immobile, multicellular and highly differentiated both externally and internally. It is characterised by the presence of golden brown xanthophylls pigment fucoxanthin which gives olive green color. Pigments lie in chromatophores. The reserve food is laminarin and mannitol. Laminarin is present in maximum quantity. The growth of plant…
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Order : Ectocarpales
Important Characteristics Plant body is branched, heterotrichous and filamentous and some are psedoparenchymatous. Plant body elongates by intercalary growth. In filamentous form the cells are arranged uniseriatly. Each cell contains chloroplast with pyrenoids. Reproduction take place both asexually and sexually. Asexual reproduction take place by plurilocular sporangia. Sexual reproduction take place by isogamy and anisogamy,…
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General Characteristics of Chlorophyceae (Green Algae)
Grass green chromatophores. Presence of starch as reserve food Members of green algae mostly green in fresh water, a few in brackish and saline water and few are terrestrial. They show wide range of variations in their thallus structure like unicellular motile (Chlamydomonas), Coenobium(Volvox), palmelloid (Tetrospora), non motile (Chlorella), Dendroid (Ecballocystis), filamentous branched (Cladophora) and unbranched (Spirogyra), heterotrichous (Coleochaete), siphonaceous…
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Order: Volvocales
General characteristics of Volvocales Plant body is unbranched filamentous, but in ulvaceae it is parenchymatous or foliaceous. Cell are uninucleate and contain chloroplast of different types like C shaped, axial or parital etc. These are found in fresh water. e. g. Ulothrix some are grown in brackish water marine water and also on soil. Plant…
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Ecological Factor: Light
Introduction Light is a significant ecological factor. Quality (wavelength or colour), duration (length of day) and intensity (energy input or actual intensity measured in gram calories) of light all influence plants and animals in various ways. Both animals and plants respond to different wavelengths of light. Colour vision occurs in majority of animals including arthropods,…