Patterns in Life: Diversity and Classification (Jeevan ke Patterns: Diversity aur Classification): Class 9 Science Chapter 12 Hinglish mein

Garden bed se ek mutthi geeli mitti uthao. Usmein India ki aabaadi se bhi zyada living things ho sakte hain: arabon bacteria, fungi ke dhaage, chhote worms, mites aur beetle grubs. Ab nazar poore desh par daalo, Ladakh ke thande deserts se Sundarbans ke mangrove swamps tak. Alag-alag living things ki ginti ki kalpana karna lagbhag namumkin ho jaata hai.

Life ki is variety ko, microbes se haathi tak aur mosses se mango trees tak, biodiversity (जैव विविधता) kehte hain. Ismein organisms ke kai kinds, ek kind ke individuals ke beech chhote differences, aur woh kai habitats shaamil hain jinmein woh rehte hain.

Is variety ke har hisse ka apna kaam hai. February mein sarson ke khet mein honeybees pollen ko ek flower se doosre flower tak le jaati hain, isliye crop mein seeds bante hain. Compost pit mein bacteria aur fungi chhilkon aur sookhi pattiyon ko wapas mitti ke liye minerals mein badal dete hain. Samundar mein, itni chhoti ki dikhe bhi nahi, aisi tairti algae hawa ki oxygen ka bada hissa banati hai. Aur har jagah green leaves sunlight trap karke woh food banati hain jis par lagbhag har food chain tiki hai.

Farmers sadiyon se is variety par bharosa karte aaye hain. Uttarakhand ki pahadiyon mein families paramparik roop se ek hi khet mein lagbhag baarah crops saath ugati thi; is system ko baranaja ('twelve grains') kehte hain: millets, pulses aur beans saath-saath. Agar sookha ek crop ko barbaad kar de, to doosri bach jaati hai aur family ko phir bhi khaana milta hai. Kai varieties wala khet pests ko bhi dheema karta hai, jo ek jaise plants ki kataaron mein tezi se phailte hain.

Itni variety ke saath scientists ise study kaise karte hain? Woh organisms ko unke common features aur unke aapas mein kitne kareebi rishte hain, iske hisaab se groups mein sort karte hain. Is sorting ko classification (वर्गीकरण) kehte hain, aur yahi is chapter ki reedh ki haddi hai.

12.1 Biodiversity Hotspot ke roop mein India

Bahut kam desh India jitne tarah ki zameen apne andar samete hain. Iski seemaon ke andar snowfields aur cold deserts, Thar ke sand dunes, baarish se bheege forests, sookha Deccan plateau, river deltas, mangrove swamps aur coral islands hain. Sirf rainfall hi Ladakh mein Leh ke aas-paas lagbhag 100 mm saal se le kar Meghalaya mein Mawsynram par 11,000 mm se zyada tak hota hai. Baarish, garmi aur mitti ka har mel plants aur animals ke alag set ke liye sahi hota hai.

Hangul, ek bada deer, sirf Kashmir ke forests mein bacha hai. Narcondam hornbill Andaman Sea ke ek chhote volcanic island par hi rehta hai. Aisi species jo naturally sirf ek region mein milti hain, endemic species (स्थानिक प्रजाति) kehlaati hain. Agar koi endemic species apne us ek ghar se gaayab ho jaye, to woh poori planet se khatam ho jaati hai.

Conservation ke liye paisa aur mehnat limited hain, isliye scientists un jagahon ko dhoondhne ke liye do-part test use karte hain jinhe sabse zyada turant protection chahiye. Biodiversity hotspot aisa region hai jismein endemic species bahut zyada hon aur jo apna zyadatar natural habitat pehle hi kho chuka ho (Fig. 12.1). Aam taur par bar yeh hai: kam se kam 1,500 endemic plant species, aur original vegetation ka kam se kam 70 % pehle hi khatam.

Duniya ke chhattees regions yeh test paas karte hain. Inmein se chaar India tak pahunchte hain. Yeh hain Himalaya, Indo-Burma (zyadatar North East), Western Ghats (Sri Lanka ke saath shared) aur Sundaland, jo India tak sirf Nicobar Islands ke zariye pahunchta hai. Inhe bachana sirf rare species ko bachana nahi hai. Jaise, Western Ghats ke forests un nadiyon ko paani dete hain jo poore southern India mein laakhon logon ko paani pahunchati hain.

12.2 Biodiversity kaise Evolve hui?

Aaj ki living world ek aisi kahani ka sirf ek frame hai jo abhi bhi chal rahi hai. Ek hi kind ke organisms ke group ko dhyaan se dekho, jaise ek farmer ke khet ke millet plants, to tumhe unke beech chhote differences milenge. Ek plant ki roots zyada gehri hoti hain, doosra kuch din pehle flower deta hai, teesre ki leaves par zyada baal hote hain. Aise kai differences parent se offspring tak pass hote hain.

Zyadatar samay yeh differences khaas matter nahi karte. Jab conditions badalti hain, to inmein se kuch matter karte hain. Lagaataar sookhe saalon mein gehri roots wale plants us paani tak pahunch sakte hain jahan doosre nahi pahunch paate, isliye unmein se zyada bachte hain aur seeds banate hain (Fig. 12.2). Unke seeds ko deep-root trait milta hai, isliye agli generation mein deep-rooted plants zyada hote hain. Ise sainkdon ya hazaaron generations tak dohrao, to ek population itna badal sakti hai ki woh life ka naya form ban jaaye.

Kisi individual plant ne paani ki zaroorat ki wajah se apni roots nahi badli; population isliye badli kyunki bachne walon ne woh aage pass kiya jo unke paas pehle se tha. Aise processes ko laakhon saal do, Earth ke har habitat mein, aur tumhe woh living world milti hai jise hum jaante hain. Yeh anginat related lekin alag forms se bani hai, jinmein se har ek purane forms se shaakha ki tarah nikla hai. Kaun kiska rishtedaar hai, yeh pata lagana classification ka kaam hai.

12.3 Organisms ko Classify kaise karein?

Grouping tum pehle se karte ho. Tum apni books subject ke hisaab se aur kapde season ke hisaab se sort karte ho. Living things ko sort karna bhi aise hi hai, bas jo rule tum chunte ho wahi tay karta hai ki har organism kis group mein jaayega. Neeche wali activity dikhati hai ki rule kitna matter karta hai.

Fig. 12.3 chhe pond organisms ke saath yahi effect dikhata hai. 'Kya yeh ud sakta hai?' se sort karne par dragonfly birds aur bat ke saath baithti hai. 'Kya iski backbone hai?' se sort karne par woh apne alag group mein chali jaati hai, jabki frog aur rohu fish birds aur bat ke saath aa jaate hain.

12.3.1 Living organisms ko classify karne ke kuch criteria

Koi field biologist jab kisi ajeeb jeev se milta hai, to woh pehle un cheezon se shuru karta hai jo nangi aankh se dikhti hain, aur phir andar ki taraf badhta hai, un features tak jinke liye microscope ya DNA laboratory chahiye. Yeh main tarah ke features compare kiye jaate hain:

• Bahari form: shape, size aur body plan. Starfish ki arms ek centre se chaaron taraf nikalti hain; earthworm ek lambi tube jaisa hai.
• Andar ki structure: skeletons, organs aur tissues. Fish ke andar backbone hoti hai; prawn ke bajaye bahar ek sakht covering hoti hai.
• Cells: ek cell ya kai; true nucleus hai ya nahi; cell wall hai ya nahi. Ek bacterium aur tumhare gaal ka ek cell.
• Food kaise milta hai: autotroph apna food khud banata hai, aam taur par photosynthesis se; heterotroph doosre organisms se food leta hai. Tulsi ka plant aur ek bakri.
• Reproduction: seeds, spores, eggs ya live birth se; ek parent se ya do se. Fern spores se phailta hai; mango tree seeds se.
• Nature mein role: producer, consumer ya decomposer. Ghaas, ek deer aur ek mushroom.
• Genes: DNA kitna milta-julta hai. DNA dikhata hai ki whales fish ke mukable hippos ke zyada kareebi rishtedaar hain.

Jab features ka poora set kai organisms mein common hota hai, to sabse simple explanation yeh hai ki unhe woh features ek common ancestor se mile. Isliye shared features family history ke clues hain, aur DNA se scientists in clues ko test kar sakte hain.

12.4 Classification ki Zaroorat

Kisi badi wholesale medicine shop mein jaao aur cough syrup maango. Shopkeeper hazaaron boxes mein se use seconds mein dhoondh leta hai, kyunki shelves sorted hain: pehle product ke type se, phir use se, phir brand se. Us order ke bina har request ka matlab hota poori shop chhaanna.

Living things to isse kahin zyada hain. Scientists ne lagbhag do million species describe ki hain, aur asli total ke andaaze aath ya nau million tak jaate hain. Kisi system ke bina koi bhi unka hisaab nahi rakh paata, unhe compare nahi kar paata, ya unke baare mein jo pata hai woh share nahi kar paata. Neeche wali case study is problem ko chhote scale par dikhati hai.

Organisms ko unke shared features se groups mein sort karna, jise scientists biological classification kehte hain, kai tareekon se faayda deta hai:

• Ek common bhasha. Chennai ka ek scientist aur Chile ka ek scientist pakka jaan sakte hain ki dono ek hi organism ki baat kar rahe hain.
• Naye aane walon ke liye jagah. Naya mila beetle uske rishtedaaron ke beech rakha ja sakta hai aur use naam diya ja sakta hai.
• Aasaan study. Millions species groups ka ek sambhalne layak set ban jaati hain jinhe ek-ek karke study kiya ja sakta hai.
• Rishte. Groups dikhate hain ki kaun se organisms kareebi rishtedaar hain aur kaun ek doosre par depend karte hain.
• Samaanta aur antar. Group ka naam turant bata deta hai ki uske members mein kya common hai.
• Conservation. Kaun si species kaun si hai, yeh jaanne se pata chalta hai ki kaun si rare hain ya ghat rahi hain, taaki unhe bachaya ja sake.

12.5 Samay ke saath Biological Classification Systems

Classification kai baar dobara banaya gaya hai, har baar isliye kyunki naye tools ne kuch aisa dikhaya jise purana system samjha nahi pa raha tha.

Greek vichaarak Aristotle ne, 4th century BCE mein, animals ko mainly unke rehne ki jagah (zameen, paani ya hawa) aur unke dikhne ke hisaab se group kiya. Yeh ek shuruaat thi, lekin habitat rule whale ko fish ke saath aur bat ko birds ke saath rakh deta hai, kyunki yeh sirf bahar dekhta hai.

1758 mein Swedish naturalist Carolus Linnaeus ne do kingdoms use kiye: Plantae, jo ek jagah rehte hain aur apna food khud banate hain, aur Animalia, jo idhar-udhar chalte hain aur doosre organisms ko khaate hain. Microscopes ne jaldi hi mushkil khadi kar di. Single-celled Paramecium animal ki tarah tairta aur khaata hai, single-celled Euglena plant ki tarah green hai phir bhi tairta hai, aur bacteria kisi bhi kingdom mein fit nahi hote.

Isliye 1866 mein Ernst Haeckel ne microscopic single-celled life ke liye teesra kingdom, Protista, joda. Phir behtar microscopes ne dikhaya ki bacteria mein true nucleus nahi hota jabki protists mein hota hai, isliye 1938 mein Herbert Copeland ne bacteria ko unke apne kingdom, Monera, mein daal diya. Aakhir mein pata chala ki fungi plants se kaafi alag hain: woh food bana nahi sakte aur use absorb karte hain, aam taur par dead matter se. 1969 mein Robert Whittaker ne unhe bhi apna kingdom diya, aur bana five-kingdom system: Monera, Protista, Fungi, Plantae aur Animalia (Fig. 12.5).

12.6 Five Kingdom Classification

Whittaker ke paanch kingdoms organism ke cells aur body ke baare mein chaar sawaalon par tike hain:

• Cell type: kya yeh prokaryote (प्राक्केंद्रकी) hai, jiska DNA cell mein khula pada hota hai, ya eukaryote (सुकेंद्रकी), jiska DNA membrane se ghire nucleus ke andar hota hai?
• Body organisation: kya organism ek single cell (unicellular) hai ya kai cells se bana (multicellular)?
• Cell wall: kya har cell ki wall hai, aur agar hai, to kya woh cellulose (jaise plants mein) ya chitin (jaise fungi mein) ki bani hai?
• Nutrition: kya yeh apna food khud banata hai, ya doosron se leta hai, aur kya woh food nigalta hai ya absorb karta hai?

In sawaalon ko sahi order mein poocho to tumhe ek key milti hai: haan-ya-nahi sawaalon ki ek chain jo theek ek kingdom tak le jaati hai (Fig. 12.6). Neeche wali activity mein ise try karo, phir Kingdom detective mein das mystery organisms par khud ko test karo.

12.6.1 Kingdom Monera — Unicellular prokaryotes

Kingdom Monera mein bacteria aur cyanobacteria hain: single prokaryotic cells, aksar sirf ek millimetre ke hazaarwe hisse jitne lambe. Yeh survival ke champions hain. Yeh Himachal Pradesh mein Manikaran ke khaulte springs mein, salt pans ke khaare paani mein aur chattaanon ke andar gehrai mein panapte hain, aur inke trillions tumhare apne gut mein rehte hain.

Kuch bacteria khatarnaak hain: woh cholera, typhoid aur tuberculosis karte hain. Zyadatar bacteria harmless hain, aur kai aise partners hain jinke bina hum reh nahi sakte. Tumhare naashte ka dahi Lactobacillus jamaata hai. Chana aur matar ke plants ko nitrogen Rhizobium se milti hai, jo unki roots par chhoti gaanthon mein rehta hai. Cattle sakht ghaas todne ke liye apne pet ke microbes par depend karte hain, aur oil spills ko pachane ke liye bhi bacteria ki safai teams use ki jaati hain.

Cyanobacteria, jinhe aksar blue-green algae kehte hain, photosynthesis se apna food khud banate hain, jo zyadatar bacteria nahi kar sakte. Isliye kingdom Monera mein autotrophs aur heterotrophs dono hain. Iske members ko jo cheez jodti hai woh hai nucleus ka na hona.

12.6.2 Kingdom Protista — Unicellular eukaryotes

Protist ek single cell hota hai, lekin ek poora eukaryote, jismein nucleus aur doosre membrane-bound parts hote hain. Kuch protists mein cell wall nahi hoti; kuch mein cellulose ki wall hoti hai. Woh har jagah rehte hain jahan paani ho: ponds, samundar aur geeli mitti mein, aur doosre organisms ke andar bhi.

Yeh bahut alag-alag tareekon se khaate hain. Euglena aur diatoms mein chloroplasts hote hain aur woh light mein food banate hain. Amoeba food particle ke around beh kar use nigal leta hai. Paramecium hilte hue cilia se bacteria ko apne gullet mein le jaata hai. Plasmodium, jo malaria karta hai, hamare blood mein parasite ban kar rehta hai.

Gaon ke pond mein food ka raasta follow karo to shuruaat ke paas hi protists milenge. Diatoms aur doosre green protists sunlight pakadte hain, water fleas unhe charte hain, aur chhoti fish water fleas ko khaati hain. Kuch aur protists bacteria aur sadte tukdon ko khaate hain, aur jo marta hai use recycle karne mein madad karte hain.

12.6.3 Kingdom Fungi — Cell wall wale multicellular, heterotrophic eukaryotes

Monsoon mein bread ka ek slice geele kitchen mein chhod do, to kuch hi dinon mein us par grey ya green rooyedaar parat ug aati hai. Woh rooyedaar cheez ek fungus hai, mushrooms aur yeasts ka rishtedaar. Zyadatar fungi multicellular eukaryotes hain jinke cells ki walls chitin ki hoti hain, wahi sakht material jo insect ki bahari covering banata hai. Inmein chlorophyll nahi hota, isliye yeh apna food khud nahi bana sakte.

Iske bajaye fungus hyphae naam ke patle dhaagon ki tarah ugta hai, jo apne food mein phail jaate hain aur saath milkar mycelium (कवकजाल) banate hain (Fig. 12.8). Dhaage food mein digestive enzymes chhodte hain aur phir ghule hue nutrients ko absorb karte hain. Zyadatar fungi isi tarah dead matter par palte hain, isliye unhe saprophytes kehte hain. Mushroom sirf woh hissa hai jo spores bikherne ke liye upar nikalta hai; fungus ki main body lakdi ya mitti mein chhupi rehti hai.

Yeast pehle ek paheli lagta hai, kyunki yeh ek single cell hai. Lekin iski wall mein chitin hai aur yeh apna food absorb karta hai, isliye yeh protists ke saath nahi, fungi ke saath aata hai. Log fungi se kai tarah ke kaam lete hain. Yeast bread ke aate ko phulata hai aur batters ko ferment karne mein madad karta hai. Mould Penicillium ne hamein penicillin di, pehli antibiotic jo bade paimaane par use hui, aur Aspergillus jaise moulds factories mein enzymes banane ke liye ugaaye jaate hain.

Socho ek aisa forest jahan kuch bhi nahi sadta: aaj tak giri har patti abhi bhi wahin padi hoti, apne minerals andar band kiye hue. Fungi, bacteria ke saath, main recyclers hain jo aisa hone se rokte hain. Kai fungi plant roots ke saath team bhi banate hain, sugar ke badle unhe paani aur minerals lene mein madad karte hain. Kuch parasites hain jo bimaariyan karte hain, jaise wheat mein rust aur insaan ki skin par ringworm. Fungi spores se phailte hain, jinhe woh mating ke saath ya bina bana sakte hain, aur garam aur geeli jagahon par khoob panapte hain.

12.6.4 Kingdom Plantae — Cell wall wale multicellular, autotrophic eukaryotes

Har plant, pond ki alga se banyan tree tak, kai eukaryotic cells se bana hai jo cellulose ki sakht walls mein band hote hain. Plants mein chlorophyll hota hai aur woh sunlight mein apna food khud banate hain. Zameen par lagbhag har food chain unse shuru hoti hai, aur jo oxygen woh chhodte hain woh hawa ko saans lene layak rakhti hai.

Kingdom Plantae paanch groups mein baanta gaya hai. Inhe order mein padho to tum plants ko paani se nikal kar aur zyada sookhi zameen ki taraf badhte dekh sakte ho, har step par ek problem solve karte hue (Fig. 12.9).

Thallophyta: sabse simple plants

Thallophytes, yaani algae, ki body simple hoti hai jise thallus kehte hain, jo root, stem aur leaves mein baanti nahi hoti (thallos ka matlab bina bati body, phyton ka matlab plant). Kyunki inke chaaron taraf paani hota hai, har cell paani, gases aur minerals seedhe le sakta hai, aur paani body ko sambhale rakhta hai. Examples hain pathreele kinaron par Ulva (sea lettuce) aur saaf ponds mein Chara; gaon ke pond ke chipchipe green dhaage bhi aksar algae hi hote hain.

Bryophyta: zameen par pehle kadam

Monsoon ke baad kisi geeli deewar par tumhe makhmali green kaleen dikh sakta hai: moss. Mosses aur liverworts bryophytes hain (bryon ka matlab moss), pehle plants jinhone zameen par jeena shuru kiya, lekin bas thoda sa. Rhizoids naam ke patle dhaage unhe pakad kar rakhte hain, aur unke simple stem jaise aur leaf jaise parts hote hain. Unmein vascular tissue nahi hota, isliye paani ko cell-dar-cell unke andar risna padta hai, jisse woh chhote rehte hain aur geeli, chhaon wali jagahon se bandhe rehte hain. Breed karne ke liye bhi unhe paani chahiye: unke male cells egg tak pahunchne ke liye baarish ya os ki patli parat mein tairte hain. Zameen par rehna lekin paani mein breed karna, isliye unhe 'amphibians of the plant world' kehte hain. Riccia (ek liverwort) aur Funaria (ek moss) common examples hain.

Pteridophyta: transport system aata hai

Ferns aur horsetails, yaani pteridophytes (pteron ka matlab feather, pankh jaise fronds ki wajah se), pehle plants the jinmein plumbing thi. Unki true roots, stems aur leaves mein vascular tissue (संवहन ऊतक) ke strands chalte hain. Xylem roots se paani aur minerals upar le jaata hai, aur phloem leaves se food baaki har hisse tak le jaata hai. Jab paani wahan pahunchta hai jahan zaroorat ho, to fern bade fronds sambhal sakta hai, aur kuch tree ferns ghar se bhi lambe ho jaate hain. Inki seemayein reproduction mein hain. Yeh seeds nahi banate, balki spores se phailte hain, aur inke male cells ko egg tak pahunchne ke liye ab bhi paani mein tairna padta hai.

Gymnosperms: bina fruits ke seeds

Gymnosperms, jaise deodar, pine aur Cycas, ne reproduction ko paani se azaad kar diya. Hawa unke pollen ko egg tak le jaati hai, isliye male cells ko ab tairna nahi padta. Aur yeh seeds banate hain: ek chhota plant jo stored food ke saath ek protective coat ke andar pack hota hai, aur thand ya sookhe ke khatam hone ka intezaar kar sakta hai. Seeds cones ke scales par khule pade hote hain (gymnos ka matlab naked, sperma ka matlab seed). Sui jaisi ya scaly leaves kam paani khoti hain, isliye gymnosperms thande, sookhe pahadi dhalaanon par khoob panapte hain.

Angiosperms: flowers aur fruits

Aaj zinda zyadatar land plants, lagbhag 3 lakh species, angiosperms hain: flowering plants, ghaas aur rice se le kar neem aur banyan tak. Inki body bhi saare plants mein sabse complex hoti hai. Do khojein inki safalta samjhati hain. Flowers insects, birds aur bats ko kheenchte hain jo hawa se kahin zyada bharose se pollen ko ek plant se doosre tak le jaate hain. Aur seeds ek fruit ke andar bante hain (angeion ka matlab vessel), jo unhe bachata hai aur door tak jaane mein madad karta hai. Birds amrood khaate hain aur seeds door gira dete hain, hawa semal ke ped ke rooyedaar seeds ko uda le jaati hai, aur coconuts samundar paar tairte hain. In faaydon ke saath angiosperms zameen ke lagbhag har habitat mein ugte hain.

Saath mein dekho to paanch groups dikhate hain ki plants ne pehle transport tissue paaya, phir seeds, phir flowers aur fruits: har ek paani se aur door rehne ka naya tareeka. Lekin koi design perfect nahi hai. Har faayde ki apni keemat hoti hai, isliye har group apni tarah ki jagah par sabse achha bachta hai.

12.6.5 Kingdom Animalia — Multicellular, heterotrophic eukaryotes

Ek bakri taazi ghaas ki taraf chalti hai, ek spider jaala bun kar intezaar karta hai, aur ek owl andhere mein chuhe ki sarsarahat sunta hai. Animals bina cell walls wale many-celled eukaryotes hain, aur inmein se koi bhi food nahi bana sakta. Food paana, aur khud food banne se bachna, yahi samjhata hai ki zyadatar animals kyun idhar-udhar chalte hain, unke sense organs aur nerves kyun pal bhar mein react karte hain, aur woh coordinated tareeke se behave kyun karte hain.

Animal kingdom ka pehla bada batwara notochord (पृष्ठरज्जु) par depend karta hai, ek lachila rod jo peeth ke saath chalta hai aur body ko sakht banata hai (Fig. 12.10). Jin animals mein yeh kabhi nahi hota woh non-chordates, yaani invertebrates hain. Jin animals mein yeh hota hai, kam se kam life ke kisi stage par, woh chordates hain. Zyadatar chordates mein notochord backbone ka pehla roop hai: jaise embryo badhta hai, uski jagah vertebral column ban jaata hai. Chordates aage protochordates aur vertebrates mein baante jaate hain.

Invertebrates: bina notochord wale animals

Invertebrate groups ko design experiments ki ek series samjho, bina asli tissues wale sponges se le kar complex organ systems wale insects tak. Har group pehle ke zyadatar features rakhta hai aur kuch naya jodta hai, aur har naya feature ek problem solve karta hai to doosri khadi bhi karta hai (Fig. 12.11).

Porifera (sponges) ka matlab hai 'pores wale'. Sponge cells ki dheeli body hai jismein true tissues ya organs nahi hote. Paani anginat pores se andar aata hai aur ek badi opening se bahar jaata hai, cells tak seedhe food aur oxygen laata hai aur wastes le jaata hai. Sponges ek jagah fixed rehte hain, lagbhag sab samundar mein; kuch, jaise Spongilla, meethe paani mein rehte hain. Paani se bahar sponge dheh kar sookh jaayega.

Cnidaria: sea anemones, jellyfish, corals aur Hydra. Pond mein Hydra apne tentacles phailaye intezaar karta hai. Jab koi water flea paas se guzarta hai, stinging cells chalte hain aur tentacles shikaar ko mouth mein dhakel dete hain. Iske liye true tissues chahiye, yaani stinging, muscle aur nerve cells ke groups jo saath kaam karein. Dikkat yeh hai ki mouth body ki akeli opening hai, isliye bina pache bache hisse ko usi raaste nikalna padta hai jisse food aaya tha.

Platyhelminthes (flatworms): pork tapeworm hooks aur suckers ke crown se insaan ke gut ke andar chipka rehta hai, aur liver fluke cattle aur sheep ke liver ke andar chipka rehta hai. Azaad rehne wala Planaria streams mein pattharon ke neeche sarakta hai. Flatworm ribbon jitna patla hota hai, isliye koi bhi cell surface se door nahi hota aur oxygen bas diffuse hokar andar aa jaati hai: lungs ya gills ki zaroorat nahi. Iska ek aage ka end bhi hota hai. Iski body 11Bilateral symmetry: sirf ek cut, head se tail tak, body ko do aaine jaise aadhe hisson mein baantta hai. bilateral symmetry dikhati hai, aur head, jahan sense organs hote hain, aage chalta hai, isliye animal maqsad ke saath chalta hai. Lekin iske gut ki abhi bhi sirf ek opening hoti hai.

Nematoda (roundworms) ek bada sudhaar laate hain: gut do openings wali tube hai, ek end par mouth aur doosre par anus. Ab food ek hi direction mein chalta hai aur stages mein process hota hai, factory line ki tarah. Inki body lambi aur gol hoti hai, aur yeh lagbhag har jagah rehte hain: mitti mein, paani mein aur hosts ke andar. Examples hain insaan ke gut mein Ascaris, hookworms, aur woh filarial worm jo elephantiasis karta hai. Male aur female worms alag hote hain.

Annelida (segmented worms): earthworms, leeches aur sea worm Nereis. Body ring jaise segments mein bati hoti hai, har ek ke apne muscles hote hain, isliye worm ek hissa khinch sakta hai jab doosra chhota ho raha ho. Gut aur body wall ke beech fluid se bhari body cavity muscles ko dhakelne ke liye kuch deti hai. Ek nerve cord movement ko coordinate karti hai, aur organs organ systems ki tarah saath kaam karte hain.

Arthropoda: insects, spiders, scorpions, crabs, prawns aur millipedes, Earth ka sabse bada animal group. Inke segments alag kaam wale body regions mein grouped hote hain, jaise insect ka head, thorax aur abdomen, aur inki legs jointed hoti hain (arthron ka matlab joint, pous ka matlab foot). Inki body ek exoskeleton mein band hoti hai jo built-in anchor points wale kavach ki tarah kaam karta hai. Jointed legs chalane ke liye muscles iske andar jude hote hain, iski waxy surface paani andar rakhti hai, aur iski sakhti dushmanon ko bahar rakhti hai. Isi tarah cockroach sookhe kitchen cupboard mein bach jaata hai, jahan earthworm kuch ghanton mein sikud jaayega.

Mollusca: snails, slugs, oysters, octopuses aur cuttlefish. Inke organs ek naram body ke andar organ systems mein organised hote hain, jo aam taur par unsegmented hoti hai, jismein head, rengne ke liye muscular foot aur organs rakhne wala kooba hota hai. Kai molluscs mein bachaav ke liye body par ek sakht shell ugta hai. Garden snail, pearl oyster aur octopus bilkul alag dikhte hain, phir bhi teenon isi ek plan ke variations hain.

Echinodermata: starfish, sea urchins, brittle stars aur sea cucumbers, sab samundar mein rehte hain. Inki skin kaantedaar hoti hai (echinos ka matlab spiny, derma ka matlab skin), aur uske neeche calcium carbonate plates ka internal skeleton hota hai, jabki inmein notochord nahi hota. Paani ke pressure se chalne wale sainkdon chhote tube feet inhe rengne aur chattaanon ko pakadne dete hain.

Aath groups ko line mein rakho to ek trend dikhta hai: true tissues, phir head end, phir aar-paar gut, phir segments, body cavities aur skeletons. Lekin zyada complex ka matlab behtar nahi hai. Sponges 500 million saal se zyada se bina ek bhi organ ke panap rahe hain, aur insect apne kavach ki keemat har baar badhne par moult karke chukata hai.

Chordates: notochord wale animals

Protochordates, jaise lancelets aur sea squirts, chhote samundari animals hain jinmein kam se kam life ke kisi stage par notochord hota hai lekin backbone kabhi nahi. Sea squirt ka larva apni tail mein notochord ke saath tairta hai, phir kisi chattaan par baith jaata hai aur use kho deta hai. Yeh is baat ke zinda ishaare hain ki pehli fish ke ancestors kaise rahe honge.

Apni peeth ke beech mein ungli phirao to tumhe ubhaaron ki ek kataar mehsoos hogi: tumhare vertebrae, woh chhoti haddiyan jo tumhari backbone banati hain. Backbone wale animals vertebrates hain. Backbone body ke andar ek mazboot lekin jointed rod hai, isliye woh bhaari body utha sakti hai aur phir bhi mud sakti hai. Muscles us se mazbooti se jude rehte hain, aur woh spinal cord ko bachati hai jabki skull brain ki raksha karta hai. Earth ke zyadatar sabse bade aur sabse tez animals vertebrates hain. Yeh paanch jaane-pehchaane groups mein aate hain, jinhe rehne ki jagah, skin ki covering, saans lene ke tareeke aur bachche paida karne ke tareeke se alag kiya jaata hai:

12.7 Structural Change ke Nateeje: Adaptations

Aaj hum animal bodies ki jo variety dekhte hain, woh bahut lambe samay mein jude structural changes ka nateeja hai, aur har body ek tarah ki zindagi ke liye fit hai. Kingfisher ki khanjar jaisi chonch ek tez dubki mein fish ko bhed deti hai. Gharial ka lamba, patla thootha paani mein side mein ghoom kar fish ko jhapat leta hai. Snow leopard ka mota fur aur lambi, ghani tail use barfeeli Himalayan dhalaanon par garam rakhte hain. Fruit bat bahut lambi ungliyon ki haddiyon ke beech tani skin ke wings se udta hai.

Mammals mein doodh banane wali glands maaon ko janm ke baad hafton ya mahinon tak apne bachchon ko khilane deti hain, jisse bachchon ke bachne ke chances bahut badh jaate hain. Aise features akele nahi, saath mein kaam karte hain: cheetah ki lambi legs, lachili spine, chaude nathune aur bada heart, sab milkar uski tez daud ko taaqat dete hain. Body forms ki range un environments ki range ko dikhati hai jinmein animals rehte hain.

12.7.1 Classification ka hierarchical nature

Classification levels mein arranged hai, jaise boxes ke andar boxes. Sabse bada box kingdom hai; uske andar chhote se chhote groups hain, species tak: Kingdom → Phylum → Class → Order → Family → Genus → Species. (Plants ke liye phylum ki jagah aksar division use hota hai.)

Har step neeche jaane par group mein kam kinds ke organisms hote hain, aur uske members zyada features share karte hain. Ek family kabhi do orders mein nahi phaili hoti; woh poori tarah ek ke andar hoti hai. Fig. 12.12 mein Indian peafowl ko levels mein neeche follow karo: kingdom Animalia mein earthworms aur crabs bhi hain, lekin genus Pavo tak sirf do tarah ke peafowl bachte hain.

Socho ek bade school mein ek student ko dhoondhna hai. 'Class 9' search ko chhota karta hai, 'Section B' aur chhota karta hai, aur roll number 23 ek insaan ko chun leta hai. Section B ke students school ke saare students ke mukable kahin zyada cheezein share karte hain (wahi timetable, teachers aur classroom). Isi tarah classification ke levels scientists ko kisi bhi organism ko theek-theek pin down karne dete hain aur turant dikha dete hain ki uske sabse kareebi rishtedaar kaun hain.

12.8 Scientific Naming — Binomial System

Roz ke naam do tarah se dikkat karte hain. Yeh jagah-jagah badalte hain, isliye ek hi fish Kolkata, Chennai aur Mumbai ke bazaaron mein teen alag naamon se bik sakti hai. Aur yeh bhatkaate hain: starfish fish nahi hai, silverfish ek insect hai, aur flying fox ek bat hai.

Scientists dono problems ko har species ko ek official naam dekar solve karte hain, jo har desh aur har bhasha mein maana jaata hai. Is system ko binomial nomenclature (द्विपद नामपद्धति) kehte hain. Carolus Linnaeus ne 18th century mein ise standard practice banaya. 'Binomial' ka matlab hai do naam: har scientific naam ke do parts hote hain, Latin ya Latin jaise form mein.

Pehla part genus (वंश) hai, yaani kareebi related species ka ek group. Doosra part species naam hai; genus ke saath milkar yeh ek species (जाति) ka naam banata hai. Indian peafowl, Pavo cristatus, aur South-East Asia ka green peafowl, Pavo muticus, genus Pavo share karte hain kyunki unki banaawat milti-julti hai, lekin woh alag species hain.

Scientific naam kuch simple rules follow karte hain:

1. Scientific naam mein do shabd hote hain: pehle genus, phir species naam.
2. Genus capital letter se shuru hota hai; species naam poora small letters mein likha jaata hai (Pavo cristatus, kabhi Pavo Cristatus nahi).
3. Print mein naam italics mein hota hai; haath se likhte samay har shabd ke neeche alag-alag line kheenchi jaati hai (Fig. 12.13).
4. Poora naam ek baar use karne ke baad genus ko uske pehle letter tak chhota kiya ja sakta hai: P. cristatus.

12.9 Evidence ke roop mein Fossils

Jharkhand ki kisi coal mine se shale ki ek slab todo, to tumhe jeebh jaisi shape ki patti ka nishaan mil sakta hai jo kisi zinda plant ki nahi hai. Yeh Glossopteris ki hai, ek plant jo lagbhag 250 million saal pehle gaayab ho gaya. Beeti life ka aisa bacha hua avshesh ya nishaan fossil (जीवाश्म) kehlata hai. Yeh haddi, shell, patti ka nishaan, pairon ka nishaan, ya amber mein phansa poora insect ho sakta hai.

Fossils tab bante hain jab koi organism keechad ya ret mein jaldi dab jaata hai. Samay ke saath upar aur layers jamti hain aur chattaan mein sakht ho jaati hain, isliye bina chhedi chattaan mein gehri layers zyada purani hoti hain (Fig. 12.14). Poori duniya mein purani layers mein zyadatar simple life milti hai, jaise bacterial mats aur shells, jabki nayi layers mein zyada complex forms milte hain, jaise land plants, reptiles aur mammals.

India mein kai aur zaroori fossil sites hain. Gujarat ke Balasinor mein Raiyoli par dinosaur ke eggs aur ghonsle mile hain. Rajasaurus narmadensis, ek maans khaane wala dinosaur, Narmada valley ke naam par hai jahan iski haddiyan khod kar nikaali gayi. Shivalik hills mein purane apes, elephants aur giraffe jaise animals ke fossils hain. Aur Narmada valley mein hi Hathnora par ek shuruaati insaan ki fossil skull mili. Saath mein yeh Earth par life ke itihaas ke panno jaise padhe jaate hain.

12.10 Khatre mein Biodiversity

Western Ghats ke forest mein ek fig tree ke baare mein socho. Iske chhote flowers, jo kachche fig ke andar chhupe hote hain, sirf fig wasps se pollinate ho sakte hain. Iske fruits saal bhar hornbills, fruit bats, macaques aur squirrels ko khilate hain, aur woh animals iske seeds ko nayi jagahon tak le jaate hain.

Agar fig wasps gaayab ho jaayein, shayad pesticides ki wajah se, to tree koi naya seed nahi bana paayega, aur figs par depend karne wala har animal bhookha rahega (Fig. 12.15). Ecologists ise cascade kehte hain: ek ka gaayab hona doosron ko bhi le doobta hai, kyunki koi species akele nahi rehti.

Insaani activities aise nuksaan ko tez kar rahi hain. Main kaaran hain:

• khet, sadkon aur shehron ke liye forests, grasslands aur wetlands ko saaf karna;
• hawa, paani aur mitti ko pollute karna;
• had se zyada shikaar, had se zyada fishing aur had se zyada ikattha karna;
• doosri jagahon se laayi gayi invasive species, jaise lakes ka dum ghotne wali water hyacinth;
• climate change, jo rainfall aur temperature ko itni tezi se badalta hai ki kai organisms adjust nahi kar paate.