Plant Kingdom

Genera like Selaginella and Salvinia which produce two kinds of spores, macro (large) and micro (small) spores, are known as heterosporous. The megaspores and microspores germinate and give rise to female and male gametophytes, respectively. The female gametophytes in these plants are retained on the parent sporophytes for variable periods. The development of the zygotes into young embryos take place within the female gametophytes. This event is a precursor to the seed habit considered an important step in evolution. Assertion – In gymnosperms, the male and female gametophytes depend on the sporophyte.

Assertion & Reason: Gametophyte Dependence in Gymnosperms Assertion (A): In gymnosperms, the male and female…

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NCERT-NEET-A mycorrhiza is a symbiotic association of a fungus with a root system.

Mycorrhiza and Plant Symbiosis Table Aspect Details Symbiotic Association Mycorrhiza is a symbiotic relationship between…

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NEET-NCERT-The leaves in gymnosperms are well-adapted to withstand extremes of temperature, humidity and wind. In conifers, the needle-like leavesreduce the surface area. Their thick cuticle and sunken stomata alsohelp to reduce water loss

Pinus and Cycas Comparison Category Pinus Cycas MCQs Correct Answer General Description Pinus, commonly known…

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The gymnosperms (gymnos : naked, sperma : seeds) are plants in whichthe ovules are not enclosed by any ovary wall and remain exposed, bothbefore and after fertilisation. The seeds that develop post-fertilisation, arenot covered, i.e., are naked.

Gymnosperms Table Category Description MCQs Correct Answer Definition Gymnosperms (gymnos: naked, sperma: seeds) are a…

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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-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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