Prof. Siddharth Sanghvi – Page 11

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 / Prof. Siddharth Sanghvi

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 »

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

Living World, NCERT LINE BY LINE, pre-class / Prof. Siddharth Sanghvi

Step Process Description 1 Characterization Scientists study and describe the morphology, anatomy, physiology, and other characteristics of organisms. 2 Identification By analyzing the characteristics, scientists determine the specific species, genus, family, etc., of an organism. 3 Classification Based on the characteristics, scientists group similar organisms together into categories (taxa). 4 Nomenclature Scientists assign names to

NCERT-NEET-characterisation, identification, classification and nomenclature are the processes that are basic to taxonomy. Read More »

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).

Molecular Basis of Inheritance, NCERT LINE BY LINE, pre-class / Prof. Siddharth Sanghvi

Step Enzymes Involved Details Prokaryotic vs Eukaryotic Differences Initiation Helicase, Primase Helicase unwinds the DNA helix at the origin of replication. Primase synthesizes RNA primers to provide a starting point for DNA synthesis. Replication occurs at the replication fork, a small opening in the DNA helix. Prokaryotes: Single origin of replication. Eukaryotes: Multiple origins of

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). Read More »

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

NCERT LINE BY LINE, Plant Kingdom, pre-class / Prof. Siddharth Sanghvi

Name of System Given by Basis Merits Drawbacks Artificial System Linnaeus Gross superficial morphological characters such as habit, colour, number and shape of leaves; based mainly on vegetative characters or androecium structure Simple and easy to use Quick identification Separates closely related species based on a few characteristics Gives equal weightage to vegetative and sexual

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 Read More »

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

Biological Classification, NCERT LINE BY LINE, Plant Kingdom, pre-class / Prof. Siddharth Sanghvi

Classification System Kingdoms Included Description Basis of Classification Very Early Classification – Non-scientific. Was done instinctively not using criteria that were scientific but borne out of a need to use organisms for our own use – for food, shelter and clothing. First Early Scientific Classification 1. Plantae2. Animalia Aristotle was the earliest to attempt a

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 Read More »

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.

Biological Classification, NCERT LINE BY LINE, pre-class / Prof. Siddharth Sanghvi

Type Characteristics Viruses – Non-cellular organisms with inert crystalline structure outside the living cell. – Infect host cells and take over their machinery to replicate, killing the host. – Recognized by Dmitri Ivanowsky (1892) as causal organisms of tobacco mosaic disease. – Named “virus” by M.W. Beijerinek (1898). – W.M. Stanley (1935) showed viruses could

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. Read More »

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

Cell Cycle and Division, NCERT LINE BY LINE, pre-class / Prof. Siddharth Sanghvi

Stage Characteristics G1 Phase Interval between mitosis and DNA replication initiation. Cell grows and carries out normal metabolism. Organelles are duplicated. S Phase DNA synthesis or replication occurs. DNA content doubles from 2C to 4C, but chromosome number remains the same (2n). Centriole duplicates in the cytoplasm in animal cells. G2 Phase Preparation for mitosis.

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 Read More »

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.

Biological Classification, NCERT LINE BY LINE, pre-class / Prof. Siddharth Sanghvi

Fungal Classes Comparison Characters Phycomycetes Ascomycetes Basidiomycetes Deuteromycetes Habitat Aquatic habitats, decaying wood in moist and damp places, obligate parasites on plants. Saprophytic, decomposers, parasitic, coprophilous (growing on dung). Soil, logs, tree stumps, living plant bodies as parasites (rusts, smuts). Saprophytes, parasites, decomposers of litter, help in mineral cycling. Mycelium Aseptate and coenocytic. Branched and

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. Read More »

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

Biological Classification / Prof. Siddharth Sanghvi

Kingdom Fungi Aspect Details Introduction The fungi constitute a unique kingdom of heterotrophic organisms showing great diversity in morphology and habitat. Common Examples Fungi on moist bread and rotten fruits, mushrooms, toadstools, parasitic fungus on mustard leaves, yeast used in bread and beer, wheat rust-causing Puccinia, antibiotic source Penicillium. Habitat Cosmopolitan; found in air, water,

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

Concept Map on Protista by Prof. Siddharth Sanghvi Sir for NEET

Biological Classification, NCERT LINE BY LINE / Prof. Siddharth Sanghvi

Responsive Table Characteristics of Unicellular Eukaryotes Unicellular eukaryotes Primarily aquatic Link between plants (Algae), fungi, and animals Well defined nucleus & membrane-bound organelle Mode of Nutrition – Photosynthetic (holophytic); holozoic Euglena – Mixotrophic Reproduction Asexual or vegetative – Budding, binary fission, multiple fission Sexual reproduction by cell fusion e.g. conjugation in paramecium Characteristics Diatoms Dinoflagellates

Concept Map on Protista by Prof. Siddharth Sanghvi Sir for NEET Read More »