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The Pteridophytes include horsetails and ferns. Pteridophytes are used for medicinal purposes and as soil-binders. They are also frequently grown as ornamentals. Evolutionarily, they are the first terrestrial plants topossess vascular tissues – xylem and phloem.The pteridophytes are found in cool, damp, shady places though some may flourish well in sandy-soil conditions.

Feature Description General Characteristics of Pteridophyta Common Name Pteridophytes Groups Included Horsetails and ferns Uses…

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Algae are chlorophyll-bearing, simple, thalloid, autotrophic and largelyaquatic (both fresh water and marine) organisms. They occur in avariety of other habitats: moist stones, soils and wood. Some of them also occur in association with fungi (lichen) and animals (e.g., on sloth bear).

Feature Description General Characteristics of Algae Common Name Algae Habitat Aquatic (freshwater and marine), moist…

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NCERT-NEET-Bryophytes include the various mosses and liverworts that are found commonly growing in moist shaded areas in the hills

Feature Description Common Name Bryophytes Habitat Moist, shaded areas, damp, humid localities, hills, stream banks,…

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NCERT-NEET-During the life cycle of any sexually reproducing plant, there is an alternation of generations between gamete producing haploid gametophyte and spore producing diploid sporophyte.

Life Cycle Type Definition Mitosis and Meiosis Sporophyte Gametophyte Examples (Haplontic) Organism spends most of…

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NCERT-NEET-Bacteria are the sole members of the Kingdom Monera. They are the most abundant micro-organisms. Bacteria occur almost everywhere. Hundreds of bacteria are present in a handful of soil. They also live in extreme habitats such as hot springs, deserts, snow and deep oceans where very few other life forms can survive. Many of them live in or on other organisms as parasites

Category Description General Characteristics Bacteria are the sole members of Kingdom Monera. They are the…

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NCERT-NEET-Algae are chlorophyll-bearing, simple, thalloid, autotrophic and largelyaquatic (both fresh water and marine) organisms. They occur in avariety of other habitats: moist stones, soils and wood. Some of them also occur in association with fungi (lichen) and animals (e.g., on slothbear).

Algae and their Main Characteristics Category Description Examples Habitat Chlorophyll-bearing, simple, thalloid, autotrophic, and largely…

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NCERT-NEET-classification within angiosperms to understand some of the concerns that influenced the classification systems. The earliest systems of classification used only gross superficial morphological characters such as habit, colour, number and shape of leaves, etc. They were based mainly on vegetative characters or on the androecium structure (system given by Linnaeus). Such systems were artificial; they separated the closely related species since they were based on a few characteristics. Also, the artificial systems gave equal weightage to vegetative and sexual characteristics; this is not acceptable since we know that often the vegetative characters are more easily affected by environment

Name of System Given by Basis Merits Drawbacks Artificial System Linnaeus Gross superficial morphological characters…

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NEET-NCERT-In Linnaeus’ time a Two Kingdom system of classification with Plantae and Animalia kingdoms was developed that included all plants and animals respectively. This system did not distinguish between the eukaryotes and prokaryotes, unicellular and multicellular organisms and photosynthetic (green algae) and non-photosynthetic (fungi)organisms. Classification of organisms into plants and animals was easilydone and was easy to understand, but, a large number of organisms did not fall into either category. Hence the two kingdom classification used for a long time was found inadequate. Besides, gross morphology a need was also felt for including other characteristics

Classification System Kingdoms Included Description Basis of Classification Very Early Classification – Non-scientific. Was done…

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NCERT-NEET-In the five kingdom classification of Whittaker there is no mention of lichens and some acellular organisms like viruses, viroids and prions. These are briefly introduced here.

Type Characteristics Viruses – Non-cellular organisms with inert crystalline structure outside the living cell. –…

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NCERT-NEET-The morphology of the mycelium, mode of spore formation and fruiting bodies form the basis for the division of the kingdom into various classes.

Fungal Classes Comparison Characters Phycomycetes Ascomycetes Basidiomycetes Deuteromycetes Habitat Aquatic habitats, decaying wood in moist…

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