NCERT LINE BY LINE

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.

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.

NCERT LINE BY LINE, Plant Kingdom, pre-class /

Gymnosperms Table Category Description MCQs Correct Answer Definition Gymnosperms (gymnos: naked, sperma: seeds) are a group of plants where the seeds are not enclosed in an ovary. Instead, the seeds are exposed or “naked.” 1. What does “gymnos” mean in gymnosperms? a) Seed b) Plant c) Naked d) Enclosed 2. What does “sperma” mean in […]

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. Read More »

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.

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.

NCERT LINE BY LINE, Plant Kingdom, pre-class /

Feature Description General Characteristics of Pteridophyta Common Name Pteridophytes Groups Included Horsetails and ferns Uses Medicinal purposes, soil-binders, ornamental plants Evolutionary Significance First terrestrial plants to possess vascular tissues (xylem and phloem) Habitat Cool, damp, shady places; some in sandy-soil conditions Dominant Phase Sporophyte (differentiated into true root, stem, and leaves) Leaves Small (microphylls) as

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. Read More »

During replication and transcription a nucleic acid was copied to form another nucleic acid. Hence, these processes are easy to conceptualise on the basis of complementarity. The process of translation requires transfer of genetic information from a polymer of nucleotides to synthesise a polymer of amino acids. Neither does any complementarity exist between nucleotides and amino acids, nor could any be drawn theoretically. There existed ample evidences, though, to support the notion that change in nucleic acids (genetic material) were responsible for change in amino acidsin proteins. This led to the proposition of a genetic code that could directthe sequence of amino acids during synthesis of proteins.

During replication and transcription a nucleic acid was copied to form another nucleic acid. Hence, these processes are easy to conceptualise on the basis of complementarity. The process of translation requires transfer of genetic information from a polymer of nucleotides to synthesise a polymer of amino acids. Neither does any complementarity exist between nucleotides and amino acids, nor could any be drawn theoretically. There existed ample evidences, though, to support the notion that change in nucleic acids (genetic material) were responsible for change in amino acidsin proteins. This led to the proposition of a genetic code that could directthe sequence of amino acids during synthesis of proteins.

Molecular Basis of Inheritance, NCERT LINE BY LINE, pre-class /

Concept Description Genetic Code The set of rules by which information encoded in genetic material is translated into proteins. Replication and Transcription Processes that involve copying a nucleic acid to form another nucleic acid based on complementarity. Translation Process requiring transfer of genetic information from nucleotides to synthesize a polymer of amino acids. Complementarity Exists

During replication and transcription a nucleic acid was copied to form another nucleic acid. Hence, these processes are easy to conceptualise on the basis of complementarity. The process of translation requires transfer of genetic information from a polymer of nucleotides to synthesise a polymer of amino acids. Neither does any complementarity exist between nucleotides and amino acids, nor could any be drawn theoretically. There existed ample evidences, though, to support the notion that change in nucleic acids (genetic material) were responsible for change in amino acidsin proteins. This led to the proposition of a genetic code that could directthe sequence of amino acids during synthesis of proteins. Read More »

The split-gene arrangements represent probably an ancientfeature of the genome. The presence of introns is reminiscent of antiquity,and the process of splicing represents the dominance of RNA-world. In recent times, the understanding of RNA and RNA-dependent processes in the living system have assumed more importance.

The split-gene arrangements represent probably an ancientfeature of the genome. The presence of introns is reminiscent of antiquity,and the process of splicing represents the dominance of RNA-world. In recent times, the understanding of RNA and RNA-dependent processes in the living system have assumed more importance.

Molecular Basis of Inheritance, NCERT LINE BY LINE /

Aspect Description Distinguishing RNA Subsets In early cells that lacked DNA, a crucial problem was differentiating between two types of RNAs: messenger RNAs (mRNAs) that code for proteins, and heritable genetic RNAs that propagate genetic information through generations. Role of Introns Scientists proposed that introns could serve as markers for these RNA subsets, directing them

The split-gene arrangements represent probably an ancientfeature of the genome. The presence of introns is reminiscent of antiquity,and the process of splicing represents the dominance of RNA-world. In recent times, the understanding of RNA and RNA-dependent processes in the living system have assumed more importance. Read More »

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).

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).

NCERT LINE BY LINE, Plant Kingdom, pre-class /

Feature Description General Characteristics of Algae Common Name Algae Habitat Aquatic (freshwater and marine), moist stones, soils, wood, in association with fungi (lichen), on animals (e.g., sloth bear) Plant Kingdom Chlorophyll-bearing, simple, thalloid, autotrophic organisms Form and Size Highly variable, from colonial forms (Volvox) to filamentous forms (Ulothrix, Spirogyra), massive plant bodies (kelps) Vegetative Reproduction

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). Read More »

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

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

NCERT LINE BY LINE, Plant Kingdom, pre-class /

Feature Description Common Name Bryophytes Habitat Moist, shaded areas, damp, humid localities, hills, stream banks, marshy ground, damp soil, tree bark Plant Kingdom Amphibians of the plant kingdom (live in soil, dependent on water for sexual reproduction) Role in Plant Succession Important in plant succession on bare rocks/soil Plant Body Thallus-like, prostrate or erect, attached

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

NCERT-NEET-An intriguing question is that how is the RNA polymerases able to catalyse all the three steps, which are initiation, elongation and termination. The RNA polymerase is only capable of catalysing the process of elongation. It associates transiently with initiation-factor (σ)and termination-factor (ρ) to initiate and terminate the transcription, respectively. Association with these factors alter the specificity of theRNA polymerase to either initiate or terminate

NCERT-NEET-An intriguing question is that how is the RNA polymerases able to catalyse all the three steps, which are initiation, elongation and termination. The RNA polymerase is only capable of catalysing the process of elongation. It associates transiently with initiation-factor (σ)and termination-factor (ρ) to initiate and terminate the transcription, respectively. Association with these factors alter the specificity of theRNA polymerase to either initiate or terminate

Molecular Basis of Inheritance, NCERT LINE BY LINE /

Feature Description Definition The process of copying genetic information from one strand of DNA into RNA. Principle of Complementarity Follows the principle of complementarity where adenosine pairs with uracil instead of thymine. Strands Involved Only one strand of the DNA (template strand) is copied into RNA. The other strand is the coding strand. Transcription Unit

NCERT-NEET-An intriguing question is that how is the RNA polymerases able to catalyse all the three steps, which are initiation, elongation and termination. The RNA polymerase is only capable of catalysing the process of elongation. It associates transiently with initiation-factor (σ)and termination-factor (ρ) to initiate and terminate the transcription, respectively. Association with these factors alter the specificity of theRNA polymerase to either initiate or terminate Read More »

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.

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.

NCERT LINE BY LINE, Plant Kingdom, pre-class /

Life Cycle Type Definition Mitosis and Meiosis Sporophyte Gametophyte Examples (Haplontic) Organism spends most of its life cycle in the haploid (n) stage. The only diploid (2n) stage is the zygote, which undergoes meiosis to produce haploid spores. Mitosis occurs in the haploid phase. Meiosis is zygotic, occurring in the diploid zygote to produce haploid

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. Read More »

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

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

Biological Classification, NCERT LINE BY LINE, pre-class /

Category Description General Characteristics Bacteria are the sole members of Kingdom Monera. They are the most abundant micro-organisms, found almost everywhere, including extreme habitats (hot springs, deserts, snow, deep oceans). Many are parasitic. Shapes of Bacteria – Coccus (pl. cocci): Spherical – Bacillus (pl. bacilli): Rod-shaped – Vibrio (pl. vibrios): Comma-shaped – Spirillum (pl. spirilla):

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 Read More »

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).

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).

NCERT LINE BY LINE, Plant Kingdom, pre-class /

Algae and their Main Characteristics Category Description Examples Habitat Chlorophyll-bearing, simple, thalloid, autotrophic, and largely aquatic (both freshwater and marine) organisms. They occur in a variety 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). Lichen, Marine algae (on sloth

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). Read More »