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• These are quick revision NEET NCERT Biology Class 11 notes

Characteristics of Living things

• Growth is an increase in mass and number of cells.
• Growth is fundamental in living beings but not a defining property
• Non-living things grow through extrinsic growth, by accumulation (e.g., mountains accumulating snow).
• Reproduction is the production of new individuals; it is fundamental but not exclusive to living organisms.
• Some organisms cannot reproduce (e.g., mules, worker bees, sterile humans).
• In unicellular organisms, reproduction is synonymous with growth.
• Metabolism includes all chemical reactions within a living organism; it distinguishes life forms.
• Isolated reactions in vitro (outside the body) are neither living nor non-living.
• Consciousness is the ability to detect and respond to environmental changes
• Plants respond to factors like light, water, and temperature.
• Photoperiod affects reproduction in plants and animals.
• Humans have self-consciousness.
• Patients in comas are supported by machines and are considered neither fully living nor dead.

Diversity in Living World

• Biodiversity refers to the number and variety of organisms on Earth.
• About 1.7 to 1.8 million species are known and described.
• Nomenclature is the standardized naming of organisms used worldwide, developed by Carolus Linnaeus.
• Identification correctly determines an organism's features.
• ICBN stands for the International Code for Botanical Nomenclature.
• ICZN is the International Code for Zoological Nomenclature.
• ICVN is the International Code for Virus Nomenclature.
• ICNCP is the International Code of Nomenclature for Cultivated Plants.
• Binomial nomenclature has two parts: genus and species.
• Binomial Nomenclature uses Latin words, written in italics or underlined
• The first word starts with a capital letter (genus), and the second with a small letter (species)
• The author's name appears after the species epithet.

Taxonomic Categories

• Taxonomy is the science of classifying organisms based on characteristics, identification, classification, and nomenclature.
• Taxa are specific characteristics by which organisms are assigned to categories.
• A taxon is a level of grouping organisms based on common, observable characteristics.
• The hierarchy of taxonomic categories includes kingdom, phylum/division, class, order, family, genus, and species.
• Species consist of organisms with fundamental similarities, like the indica in Mangifera indica
• A genus is is a group of related species, such as Solanum
• A family is a group of related genera (e.g., Felidae, Canidae, Solanaceae).
• Assemblages of families with similar characters create an order (e.g., Polymoniales, Primata, Carnivora).
• Class represents related orders, such as Mammalia (order Primata), Insecta.
• Phylum represents related classes, such as Chordata, Arthropoda.
• A kingdom represents related phyla, such as Animalia, Plantae.
• Lower taxa have more characteristics members per group

Taxonomical Aid Notes

• Herbarium is a storehouse of collected plant specimens that are dried, pressed, and preserved on sheets.
• Sheets in herbarium carry information such as collection date and place, local and botanical names, and collector's name
• Botanical gardens are collections of living plants grown for identification and study.
• Plants are labeled with their botanical/scientific names and families.
• Indian Botanical Garden (Howrah), National Botanical Garden (Lucknow), and Royal Botanical Garden (Kew) form good examples
• Museums collect and preserve plant and animal specimens.
• Specimens are preserved in containers with formalin solution or as dry specimens. Skeletons of animals and extinct or endangered species are also kept.
• Insects are preserved in insect boxes after collecting, killing, and pinning.
• Larger animals (birds, mammals) are stuffed and preserved.
• Zoological parks keep wild animals in protected environments under human care, allowing the study of food habits, behavior, and gestation periods e.g., Jim Corbett National Park, Gir Forest
• Keys are used for identifying plants and animals based on similarities and dissimilarities using contrasting characters in pairs of couplets; each statement is known as a lead and is analytical in nature
• Flora give information about plants in a particular area, with an actual account of habitat and distribution.
• Manuals provide information for identifying names of various species in an area.
• Monographs provide information on any one taxon.
• Catalogues list species alphabetically, describing their features for a particular place.

Classification

• Aristotle classified organisms into Enaime (have RBCs) and Anaime (absence of RBCs).
• Linnaeus classified all organisms into Plantae and Animalia
• Two-system classification did not distinguish between eukaryotes and prokaryotes, unicellular and multicellular organisms, photosynthetic and non-photosynthetic organisms.

Higher Level Classifcation

• Haeckel proposed the 3 kingdom classification: Protista, Animalia, and Plantae
• Copeland proposed the 4 kingdom classification: Monera, Protista, Animalia, and Plantae.
• R.H. Whittaker proposed 5 kingdom classification in 1969: Monera, Protista, Fungi, Animalia, and Plantae, used cell structure, body organization, mode of nutrition, reproduction, and phylogenetic relationship
• Woese proposed divided Monera into archaebacteria and eubacteria which created 6 kingdom or 3 domain classification

Kingdom Monera

• Bacteria are the sole members and are the most abundant organisms.
• Some bacteria are autotrophic and synthesize their own food from inorganic substances; others are heterotrophic and depend on other organisms for food.
• Archaebacteria live in harsh habitats due to their cell wall structure and include halophiles in salty areas, thermoacidophiles in hot springs, and methanogens in marshy areas which are present in the gut of ruminant animals to produce methane.
• Eubacteria are true bacteria with rigid cell walls and, if motile, flagella, including photosynthetic autotrophs like cyanobacteria (blue-green algae) which have chlorophyll a similar to plants, can be unicellular, colonial, or filamentous, and whose colonies are surrounded by a gelatinous sheath; they can also fix atmospheric nitrogen.
• Some specialized cells of cyanobacteria, called heterocysts, fix atmospheric nitrogen.
• Heterotrophic bacteria are mostly decomposers that help in making curd from milk, production of antibiotics, fixing nitrogen in legumes but can cause diseases like cholera, typhoid, citrus canker, and tetanus.
• Reproduction is mainly by fission; under unfavorable conditions, bacteria produce spores and can also undergo sexual reproduction by adopting primitive type DNA transfer known as Genetic Recombination.
• Mycoplasmas lack cell walls, are the smallest living cells, can survive without oxygen and are pathogenic in plants and animals.

Kingdom Protista

• There are single celled eukaryotes that are aquatic
• Reproduction is sexually and asexually with cell fusion and zygote formation
• Chrysophytes include diatoms and golden algae desmids that passively float in fresh and marine water currents plankton
• In diatoms, cell walls form 2 thin overlapping shells which fit like a soap box, indestructible from silica deposits, and accumulate diatomaceous earth which is used in filtration, oil and polishing
• Dinoflagellates are mostly marine and photosynthetic and are yellow, green, brown, blue, or red depending on pigment; their cell wall has stiff cellulosic plates on outside and have 2 flagella, and red ones release toxins leading to red tides.
• Slime molds are saprophytic protists that engulf organic material, form aggregation plasmodium in suitable conditions but form fruiting bodies bearing spores in unfavorable condition that are resistant and dispersed by air current.
• Protozoans are heterotrophs that live as predators or parasites.
• Amoeboid protozoans live in fresh water, sea, or soil and move and capture prey by pseudopodia but marine forms have silica shells.
• Flagellated protozoans are free-living or parasitic and cause sleeping sickness through Trypanosoma
• Ciliated protozoans are aquatic, have thousands of cilia, and steer food into their gullet via water current. Sporozoans have infectious spore-like stages called sporozoites, (e.g., Plasmodium).

Kingdom Fungi

• Kingdom Fungi are heterotrophic, cosmopolitan, occur in air, water, soil grow in warm, humid places, have cell walls made of chitin and polysaccharide
• Filamentous except unicellular yeast and long, slender thread like structures - hyphae
• Network of hyphae - mycelium made of continuous tubes filled with multinucleated cytoplasm (coenocytic) or have septae or cross walls in their hyphae
• Yeast - bread and beer, Puccinia cause wheat rust, Penicillium forms antibiotic penicillin
• Absorb organic matter from dead substrates - saprophytic (depend on living plants and animals - parasites
• Some dependent on living plants and animals are parasites; some live as symbionts with algae called lichens or with higher plant roots called mycorzhiza
• Reproduce vegatatively, asexually or sexually
• Vegetative - fragmentation, fission, budding
• Asexual - spores called conidia or sporangiospores or zoospores
• Sexual - oospores, ascospores, basidiospores
• Varies produced in fruiting bodies
• fusion Plasmogamy fusion of protoplasm + karogamy fusion of 2 nuclei leading to meiosis Phycomycetes: Aseptate and coenocytic mycelium that are aquatic and grows on decaying wood in moist, damp places
• Asexual by endogenous zoospores or aplanospores non motile and sexual reproduction creates isogamous or anisogamous or agamous ( bbread mold, Mucor, Albugo Plant parasites)
• Ascomycetes: sac fungi, mostly multicelluar ( Penicillum) rarely unicellular ( yeast)
• Sacrophytes, ducomposes parasite or caprophilus
• Exogenous conidia - conidiophores, sexual spores - endogenous ascospores in ascus or sac in fruiting bodies - ascocarp
• Claviceps, aspergillus, neurospora (used for Biochemical and genetic workMorels and truffles edible)
• Basidiomycetes: Branch and septate mycelium that grow in soil, logs, tree stumps, live as parasites; asexual spores not found, reproduction is very common
• Six organs lost dikaryophase rises to Basidium that produces karyogamy and meiosis into four Basidio spores exogenous
• Agricus Mushroom utelage or Smut and Pasina or rice fungi
• Deuteromycetes: imperfect (only a sexual phases known, when sexual faces no they move to ascomycetes and basiomycetes)
• reproduct asexual spores codina Mineral cycle decompositions

Kingdom Plantae

• Eukaryotes, chlorophyll containing organisms, some insectivorous bladder word and various fruit trap - Cuscutta parasitic, 2 phases the plant is double and it's supported and upload and it can also generate in alteration of generation
• Red algae, multicellular marine environments with water surface the great depth, pigment erythrobin which contains chlorophyll AD floorin starch cell wall cellulose pectin polysulphate
• Lack fragella in fragmentation no model sports

Other Biological Entities

• Virus: Non cellular, intercrystalline structure while outside host but will host them take over machinary killing. The host and reproducing.
• Virus means venom (pasteur)
• Recognizant microbes smaller than bacteria ( DJ)
• Extracted plans from tobacco extract calls infection or can tagium Vivume fluidiume
• Virus can crystalize (Stanley)
• Viruses lack both RNA and DNA and are nuclear proteins and have singular stands of RNA infecting plants with single or double stands and animals. Double or single stands may exist
• Virus that infects bacteria (Batteria Page) - Walled and double standard DNA: Has small subunits - protects capsid nucleic acids or polyhedral forms
• Mumps , Small pox, herpes, influenza, AIDS, COVID
• Disease mosaics form. Leaf roll in yellow ring:
• Vroids: - virus smaller cause potato spindle tuber disease (free RNA smaller with low weight)
• Prions: Ab normally folded proteins the same size which cause form in cattle to cr Jacob

Summary of Key Biological Associations

• Lichens:- (association between algae and fungi. They algae prepare food and shelter by absorbing minerals) Fungi is component algal is by component my cobiot, don't grow in polluted area SO2)