Structural Organisation in Animals: Class 11 Biology Chapter 7 Hinglish mein

Gaon ke talaab mein rehne wala ek Amoeba apni poori zindagi ek hi cell ke andar jeeta hai. Wahi cell khaana leta hai, gases exchange karta hai, waste bahar phenkta hai aur reproduce karne ke liye do mein bant jaata hai. Usi talaab ke kinaare baitha frog is tarah kaam nahi kar sakta. Uski body mein, tumhari body ki tarah, bahut zyada cells hote hain,112013 ke ek kaafi quote kiye jaane wale estimate ke hisaab se ek adult human body mein lagbhag $3.7\times {10}^{13}$ cells hote hain, yaani kareeb 37 trillion. aur koi akela cell itni badi body ko khila, bacha ya hila nahi sakta. Isliye cells specialise karte hain: har group ek kaam sambhalta hai aur baaki sab ke liye doosre groups par depend karta hai. Yeh chapter poochta hai ki yeh teamwork kaise arrange hota hai, aur phir ek vertebrate, frog, ko uski skin se andar tak dekhta hai.

Teamwork ka pehla level tissue (ऊतक) hai. Ek jaise cells saath-saath rehte hain, apne beech banaye gaye material (intercellular substance) mein bandhe hote hain, aur ek khaas kaam share karte hain. Animal bodies dekhne mein bahut alag lagti hain, phir bhi har complex animal, earthworm se lekar elephant tak, sirf chaar basic tarah ke tissues se bana hota hai: epithelial, connective, muscular aur neural (Table 7.1).

Tissues aage chalkar organs banate hain. Heart, liver ya kidney mein har tissue ek fixed amount mein aur ek fixed pattern mein arranged hota hai, aur yahi arrangement us structure ko ek organ banata hai. Organs ka aisa set jo ek kaam par milkar kaam kare, aur physical contact, chemical messages ya dono se juda ho, organ system kehlata hai: kidneys, ureters aur urinary bladder milkar excretory system banate hain. Fig. 7.1 mein levels ko neeche se upar chadho, to aakhri step poora frog hai.

Itni mehnat kyun? Mumbai ke dabbawalas ke baare mein socho, jo har working day ghar ka bana lunch offices tak pahunchate hain. Ek team dabbe collect karti hai, doosri station par unhe sort karti hai, teesri local trains mein safar karti hai aur chauthi deliver karti hai. Koi bhi team akele poora kaam nahi kar sakti, phir bhi milkar woh shayad hi kabhi koi dabba khote hain. Body bhi isi principle par chalti hai, division of labour. Cells, tissues, organs aur organ systems sab kaam ka ek hissa lete hain, aur body isliye zinda rehti hai kyunki har part baaki parts par depend karta hai aur unke saath coordinated rehta hai.

7.1 Organ aur Organ System

Yahi layering body ke bahut saare cells ko efficiently aur ek saath taal-mel mein kaam karne deti hai. Ek meal, ek hormone ya ek nerve signal sahi cells tak sahi samay par pahunchta hai kyunki har organ ek defined role wale system ka hissa hai, aur systems ek doosre se jude hue hain.

Ek organ ek tarah ka tissue bhi use kar sakta hai ya kai tarah ke. Frog ke stomach ki wall (Fig. 7.2) ko kaato to tum chaaron tissues ko paar karte ho. Andar ki taraf ek epithelium cavity ko line karta hai aur digestive juices chhodta hai. Uske neeche connective tissue blood vessels ko sambhalta hai. Phir muscle ki layers aati hain jo khaane ko churn karti hain, aur unke beech nerve cells ka ek network hota hai jo muscle ko batata hai ki kab sikudna hai. Tumhara heart bhi ek aisa organ hai jiski wall mein chaaron basic tissues hote hain.

Ek organ system ko kai animal groups mein compare karo to pata chalta hai ki uski complexity ek pehchaane jaane wale pattern mein badalti hai. Heart iska achha example hai: fish ke heart mein do chambers hote hain, frog ke heart mein teen, aur birds aur mammals ke heart mein chaar. Aise saaf dikhne wale pattern ko evolutionary trend kehte hain; Class 12 ka evolution wala chapter aise trends ke peeche ke evidence ko dekhta hai.

Frog ko describe karne ke liye do vocabularies chahiye. Jo kuch tum bahar se note kar sakte ho, jaise uska shape, colour, limbs aur drum jaisa tympanum, woh morphology (आकारिकी) mein aata hai, yaani form ki study; animal ke liye yeh word body aur uske parts ki bahari banawat ko cover karta hai. Botanists aur microbiologists is word ko uske sabse narrow sense mein use karte hain, sirf bahar se dikhne wale features ke liye. Jo tum sirf body kholkar dekh sakte ho, yaani andar ke organs ka form aur arrangement, woh anatomy (शारीर) mein aata hai (neeche diya comparison). Baaki chapter dono words ko frog par apply karta hai, jo hamara sample vertebrate hai.

7.2 Frogs

Pehli tez monsoon baarish ke baad kisi paddy field ke paas se guzro, to raat croaking ki aawaaz se goonj uthti hai. Frogs apni zindagi zameen aur meethe paani ke beech baantte hain, aur zoologists unhe phylum Chordata ke andar class Amphibia (Greek mein ‘double life’) mein rakhte hain. India mein jo species tumhe sabse zyada milegi woh Indian bullfrog hai, Rana tigrina,22Taxonomists ab Indian bullfrog ko genus Hoplobatrachus mein Hoplobatrachus tigerinus ke roop mein rakhte hain. NCERT aur exam papers Rana tigrina use karte hain. jo ponds, ditches aur paani bhare kheton ka ek bada frog hai.

Tum har season mein apni body ko 37 °C ke aas-paas rakhte ho. Frog aisa nahi kar sakta: uski body dhoop wale kinaare par garam hoti hai aur raat ke talaab mein thandi, yaani woh aas-paas ke temperature ke saath chalti hai (Fig. 7.3). Biologists aise animal ko poikilotherm kehte hain (aam bolchaal mein cold-blooded).33Roz ka word cold-blooded confuse karta hai, kyunki dhoop senkta poikilotherm kaafi garam ho sakta hai. Kai books ab ectotherm kehna pasand karti hain, yaani aisa animal jo apni body heat aas-paas se leta hai.

Water hyacinth ke beech chupchaap baitha frog tab tak lagbhag dikhta hi nahi jab tak woh kood na jaaye. Kai frogs apni skin ka shade background ke hisaab se gehra ya halka kar sakte hain, taaki shikaar karta snake ya heron unhe dekh na paaye. Background mein ghul-mil kar chhupna camouflage hai; NCERT is protective colouration ko mimicry kehta hai, isliye exam questions mein yahi word expect karo.44Strictly dekhein to biologists mimicry tab kehte hain jab ek species doosri species jaisi dikhne lagti hai, aur camouflage background mein ghul-mil jaane ke liye.

Frogs ke paas mushkil season jhelne ke do tareeke hain, aur dono mein zameen khodna shaamil hai. Aestivation (summer sleep) unhe sabse garam hafton se nikaalta hai, aur hibernation (winter sleep) sabse thande hafton se. Dono mein frog ek gehre burrow mein panaah leta hai, jahan mitti garmi ya sardi ko kam kar deti hai, aur uske body processes bahut dheeme ho jaate hain. Isiliye tez garmi ya kadaake ki sardi mein tumhe frogs kam hi dikhte hain (neeche diya comparison).

7.2.1 Morphology

Frog kabhi paani nahi peeta. Use jitna paani chahiye, woh sab uski skin se andar soak hota hai, isliye skin ko hamesha nam rehna padta hai. Skin ki glands use mucus se dhake rakhti hain, isiliye frog chikna aur fisalne wala lagta hai. Colours se upar aur neeche ka pata chalta hai: dorsal surface aam taur par olive green hoti hai jis par gehre, irregular dhabbe hote hain, jabki ventral surface ek jaisi halki peeli hoti hai.

Upar se dekho (Fig. 7.4) to frog ka head seedha trunk se juda hota hai: adult mein na neck hoti hai na tail, isliye uski body ke sirf do regions hain, head aur trunk. Head ke sabse khaas features bahar ubhri hui aankhein hain, jinmein se har ek ko ek nictitating membrane dhak sakti hai, yaani ek transparent palak jo aankh par phisal kar paani ke andar uski hifaazat karti hai. Har aankh ke theek peeche ek gol, drum jaisi membrane hoti hai, tympanum, jo sound pakadti hai. Snout ki nok ke paas, mouth ke upar nostrils ka ek pair khulta hai.

Limbs ke dono pairs mein bahut fark hai. Hind limbs lambe aur mazboot muscles wale hote hain, frog ki chhalaang ke engine, aur har ek paanch digits mein khatam hota hai jo skin ke webs se jude hote hain aur paani mein chappu ka kaam karte hain. Forelimbs chhote hote hain, har ek mein chaar digits. Milkar limbs frog ko koodne, tairne, chalne aur zameen khodne dete hain.

Males aur females bhi alag dikhte hain, yeh sexual dimorphism ka case hai (Fig. 7.5). Do features male ki pehchaan kara dete hain. Uske paas vocal sacs hote hain, skin ki thailiyan jo call karte waqt gubbaare ki tarah phool jaati hain, aur har forelimb ke sabse andar wale (pehle) digit par ek khurdura copulatory pad hota hai. Female mein dono nahi hote.

7.2.2 Anatomy

Body cavity mein achhi tarah develop hue digestive, respiratory, circulatory, excretory, nervous aur reproductive systems hote hain (Fig. 7.6). Hum inhe ek-ek karke dekhenge, aur har baar poochenge ki yeh system kya le jaata hai: food, hawa, blood, wastes, signals ya gametes.

Digestive system

Plant khaane wale animal ke mukaable frog ka gut kaafi chhota hota hai, khaas kar intestine. Frogs carnivores hain, aur animal food sakht plant food se kahin aasaani se digest ho jaata hai, isliye lambe gut ki zaroorat nahi padti.55Tadpole, jo algae khaata hai, uski intestine kaafi lambi aur kas kar kundli jaisi mudi hoti hai. Metamorphosis ke dauraan, jab diet insects mein badalti hai, gut chhota ho jaata hai. Is system ke do parts hain: alimentary canal, yaani woh tube jisse khaana guzarta hai, aur digestive glands jo usmein juices daalti hain.

Shikaar ko muscular tongue pakadti hai, jo bilobed hoti hai, yaani nok par do lobes mein bant jaati hai. Mouth se khaana buccal cavity mein jaata hai, pharynx se hokar chhote oesophagus mein pahunchta hai aur phir stomach tak jaata hai. Stomach aage intestine ban jaata hai, jo rectum tak jaati hai, aur rectum cloaca mein khulta hai, ek chamber jo bahar ki taraf khulta hai (Fig. 7.7). Do glands is canal ki madad karti hain. Liver bile banata hai, jo gall bladder mein store hota hai, aur pancreas pancreatic juice banata hai, jismein digestive enzymes bhare hote hain.

Digestion ko canal ke teen stations ki tarah socho. Station one, stomach. Iski walls hydrochloric acid ($\mathrm{H}\mathrm{C}\mathrm{l}$) aur gastric juices secrete karti hain, jo shikaar ko ek soup jaisa, aadha digest hua mass bana deti hain jise chyme kehte hain. Station two, duodenum, small intestine ka pehla hissa. Yahan common bile duct ek saath do juices pahunchata hai: gall bladder se bile, jo fat ko chhoti-chhoti boondon mein emulsify karta hai, aur pancreas se pancreatic juice, jo carbohydrates aur proteins ko digest karta hai.66Pancreatic juice mein fat digest karne wala ek enzyme, lipase, bhi hota hai, jo bile se bani boondon par kaam karta hai. Station three, baaki intestine. Digestion yahan poora hota hai, aur products wall par lage anginat ungli jaise villi se absorb hote hain, jinmein se har ek par aur bhi baareek microvilli hote hain. Jo kuch bina digest hue bach jaata hai, woh rectum mein jaata hai aur cloaca se bahar nikalta hai.

Respiration

Frog kahan hai, isse tay hota hai ki woh saans kaise leta hai (Fig. 7.8). Kinaare par baitha frog ek saath teen surfaces use karta hai. Nostrils se andar li gayi hawa buccal cavity mein jamaa hoti hai, jiski nam lining kuch oxygen absorb kar leti hai, aur phir yeh hawa lungs mein dhakel di jaati hai; lungs se saans lene ko pulmonary respiration kehte hain. Isi beech skin bhi gases exchange karti rehti hai. Talaab mein dubki lagao to lungs ka kaam ruk jaata hai: ab akeli skin paani mein ghuli oxygen ko diffusion se leti hai, aur is tareeke ko cutaneous respiration kehte hain.

Lungs khud trunk ke aage wale hisse mein lambi, gulaabi, thaili jaisi sacs ka ek pair hain. Aestivation ya hibernation ke dauraan burrow mein dabba frog mushkil se hilta hai, aur tab gas exchange ke liye sirf apni skin par depend karta hai. Yeh ek aur wajah hai ki skin kabhi sookhni nahi chahiye.

Circulation

Leg muscle se blood ki ek boond ko wapas follow karo (Fig. 7.9). Badi veins, venae cavae, use ek patle, triangular chamber, sinus venosus, tak pahunchati hain, jo right atrium mein khaali hota hai. Wahan se blood akele ventricle mein jaata hai, jo left atrium ka lungs se jamaa kiya hua blood bhi leta hai. Ventricle ke contract hone se blood conus arteriosus mein jaata hai, jo heart ki ventral side par ek sac jaisi vessel hai, aur wahan se arteries mein. Is tarah muscular heart mein teen chambers hote hain (atria ka ek pair aur ek akela ventricle), sab ek protective membrane, pericardium, mein lipte hue, aur yeh body cavity mein upar ki taraf hota hai.

Arteries arterial system banati hain, jo blood ko har organ tak le jaata hai; veins venous system banati hain, jo use wapas laata hai. Kyunki blood heart aur vessels ke is ghere se kabhi bahar nahi nikalta, isliye frog ke achhi tarah develop hue blood vascular system ko closed kehte hain. Iske saath-saath ek doosra network bhi chalta hai, lymphatic system: lymph, use le jaane wale channels aur un channels par bane lymph nodes.

Sirf ek ventricle hone se lungs se laut kar aaya blood aur body se laut kar aaya blood bahar pump hone se pehle thoda mix ho jaate hain. NCERT is chapter ke summary mein frog ke circulation ko single kehta hai. Chapter 15 mein isi arrangement ko aur sateek tarah se incomplete double circulation kaha gaya hai: ek poore circuit mein blood heart se do baar guzarta hai, lekin dono streams poori tarah alag nahi rehtin.

Frogs mein do khaas venous links bhi hote hain jinhe portal systems kehte hain, jinmein ek vein blood ko seedha heart mein lautane ke bajaye ek organ se doosre organ mein pahunchati hai. Hepatic portal system mein yeh link intestine se liver tak jaata hai, isliye absorb kiya hua food le jaane wala blood pehle liver se guzarta hai. Renal portal system mein yeh body ke neeche wale hisson se kidneys tak jaata hai.

Frog ke blood ki ek boond ko microscope ke neeche apne blood ki ek boond ke bagal mein rakho, to ek fark turant dikhta hai: frog ke har red blood cell (RBC, yaani erythrocyte) mein ek nucleus hota hai.77Tumhare RBCs mature hote hue apna nucleus kho dete hain, jisse haemoglobin ke liye zyada jagah bachti hai. Frog ke RBCs bade aur oval bhi hote hain. Baaki banawat jaani-pehchaani hai: ek fluid, plasma, jismein RBCs, white blood cells (WBCs, yaani leucocytes) aur platelets hote hain, aur RBCs ke andar laal pigment haemoglobin hota hai. Heart ke dhakelne se blood nutrients, paani aur gases ko jahan zaroorat ho wahan pahunchata hai. Lymph ek alag fluid hai: usmein RBCs nahi hote aur blood mein milne wale kuch proteins bhi nahi hote (neeche diya comparison).

Excretion

Frog ka main nitrogenous waste urea hai, isliye woh ek ureotelic animal hai.88Paani mein rehne wala tadpole zyaadatar ammonia excrete karta hai; urea par switch metamorphosis ke saath hota hai. Blood urea ko achhi tarah develop hui kidneys ke ek pair tak le jaata hai, jo use alag kar deti hain. Har kidney compact, gehri laal aur bean ke shape ki hoti hai, aur body cavity ke peeche wale hisse mein vertebral column ke paas hoti hai. Microscope ke neeche pata chalta hai ki kidney kai uriniferous tubules, yaani nephrons, ka bundle hai, jo uski structural aur functional units hain. Ureters, urinary bladder aur cloaca ke saath milkar kidneys excretory system banati hain.

Har kidney se ek ureter cloaca tak jaata hai, lekin woh kya le jaata hai yeh frog ke sex par depend karta hai (Fig. 7.11). Male mein ureter urine aur sperms dono le jaata hai, isliye woh urinogenital duct ka kaam karta hai. Female mein ureters sirf urine le jaate hain, aur oviducts cloaca mein alag se khulte hain. Patli wall wala urinary bladder rectum ke ventral side mein hota hai aur woh bhi cloaca mein khulta hai.

Control aur coordination

Do bahut develop hue systems frog ke organs ko taal-mel mein kaam karwaate hain. Neural system nerves ke zariye tez signals bhejta hai. Endocrine system organs ko chemically coordinate karta hai, un hormones ke zariye jo endocrine glands chhodti hain. Mote taur par head se tail ki taraf list karein to frog ki khaas endocrine glands hain pineal body, pituitary, thyroid, parathyroid, thymus, adrenals, pancreatic islets aur gonads.

Nervous system ke teen divisions hain. Brain aur spinal cord milkar central nervous system banate hain. Unse nikalne wali nerves, yaani brain se cranial nerves ke das pairs aur cord se spinal nerves, peripheral nervous system banati hain, aur sympathetic aur parasympathetic nerves autonomic nervous system banati hain. Haddi ka bana ek brain box, cranium, brain ki hifaazat karta hai.

Central nervous system ko tail wale sire se aage ki taraf trace karo (Fig. 7.10). Spinal cord vertebral column ke andar chalti hai. Skull par yeh ek opening, foramen magnum, se guzarti hai aur chaudi hokar medulla oblongata ban jaati hai. Medulla ke theek aage cerebellum hota hai; yeh dono milkar hindbrain banate hain. Unke aage do optic lobes ubhre hote hain, jo midbrain banate hain. Forebrain sabse aakhir mein aata hai: ek unpaired diencephalon, phir lambe cerebral hemispheres ka ek pair, aur bilkul aage olfactory lobes.

Sense organs

Frog ke head ki side dekho to koi ear flap nahi milega: frog ka koi external ear nahi hota, aur tympanum hi uske ear ka akela part hai jo bahar se dikhta hai. Iske peeche internal ear hota hai, jo sunne ke saath-saath balance (equilibrium) ke kaam bhi aata hai. Internal ears aur eyes frog ke do well-organised sense organs hain. Eyes skull ke orbits mein lage gol (spherical) organs ka ek pair hain. Yeh simple eyes hain: har eye ek single unit ki tarah kaam karti hai, insect ki compound eye ki tarah nahi, jo kai units se bani hoti hai. Touch, taste aur smell kaafi simple organs par depend karte hain, yaani nerve endings ke aas-paas cells ke chhote clusters (Table 7.3).

Reproduction

Male system ko ek safar ki tarah seekhna sabse aasaan hai (Fig. 7.11). Sperms do testes mein bante hain, jo peele-se oval bodies hain aur peritoneum ki double fold, mesorchium, se kidneys ke upar wale hisse se chipke rehte hain. Sperms har testis se 10 se 12 patli tubes, vasa efferentia, ke zariye nikalte hain, jo bagal wali kidney mein jaakar Bidder's canal mein khulti hain. Wahan se woh urinogenital duct tak pahunchte hain aur urine ke saath cloaca tak jaate hain, jo beech mein bana chhota chamber hai jisse faecal matter, urine aur sperms sab body se bahar nikalte hain.

Female ke reproductive system ka kidneys se koi working link nahi hota: uski do ovaries bas unke paas padi rehti hain. Ova oviducts ke ek pair mein jaate hain, jinmein se har ek ka cloaca mein apna opening hota hai, isliye eggs kabhi urine ke saath duct share nahi karte. Spawning paani mein hoti hai, jahan ek mature female ek baar mein 2500 se 3000 ova chhodti hai aur woh uski body ke bahar fertilise hote hain, yaani external fertilisation. Jo hatch hota hai woh chhota frog nahi balki ek larva hota hai, tadpole, jo metamorphosis ke zariye adult form tak pahunchta hai (Fig. 7.12).

Frogs aur log

Raat mein paddy field ke busy food web ke beech mein frogs hote hain. Woh insects, spiders aur worms khaate hain, aur snakes, herons aur egrets unhe khaate hain, isliye frogs food chains aur webs ki ek zaroori kadi hain aur ecosystem ka balance banaye rakhne mein madad karte hain. Farmers ko bhi seedha faayda hota hai, kyunki frogs jo insects khaate hain unmein se kai rice aur doosri crops ke pests hain. Kuch countries mein log frogs ki muscular legs bhi khaate hain.