NCERT LINE BY LINE

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-characterisation, identification, classification and nomenclature are the processes that are basic to taxonomy.

Step Process Description 1 Characterization Scientists study and describe the morphology, anatomy, physiology, and other…

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DNA Replication – The Machinery and the Enzymes -NCERT-NEET-‘‘It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism for the genetic material’’(Watson and Crick, 1953).

Step Enzymes Involved Details Prokaryotic vs Eukaryotic Differences Initiation Helicase, Primase Helicase unwinds the DNA…

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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-Growth and reproduction are characteristics of cells,indeed of all living organisms. All cells reproduce by dividing into two,with each parental cell giving rise to two daughter cells each time they divide. These newly formed daughter cells can themselves grow and divide,giving rise to a new cell population that is formed by the growth anddivision of a single parental cell and its progeny. In other words, such cycles of growth and division allow a single cell to form a structure consisting of millions of cells

Stage Characteristics G1 Phase Interval between mitosis and DNA replication initiation. Cell grows and carries…

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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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The fungi constitute a unique kingdom of heterotrophic organisms. Theyshow a great diversity in morphology and habitat.

Kingdom Fungi Aspect Details Introduction The fungi constitute a unique kingdom of heterotrophic organisms showing…

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