Reproduction: How Life Continues (Reproduction: Jeevan Kaise Chalta Rehta Hai): Class 9 Science Chapter 11 Hinglish mein

Ek neem ka ped sau saal ya usse bhi zyada khada reh sakta hai, aur ek billi pandrah saal jee sakti hai, phir bhi der-saber dono mar jaate hain. Lekin living things ke kinds ke roop mein neem ke ped aur billiyan laakhon saalon se hain. Yeh sirf isliye mumkin hai kyunki apni zindagi khatam hone se pehle living things apne jaisi offspring banate hain. Is process ko reproduction (जनन) kehte hain. Ek species apne har member se zyada jeeti hai, kyunki har generation agli generation banati hai.

Do families ko compare karo. Billi ke chaar bachchon ke litter ki ek hi maa aur ek hi baap hai, phir bhi ek bachcha ginger hai, ek dhaariyon wala hai aur ek lagbhag kaala hai. Doosri taraf, Bryophyllum ki patti ke kinare par ugne wale chhote plantlets sab bilkul usi plant jaise ban jaate hain jisse woh patti aayi thi. Yeh do tasveerein living things ke reproduce karne ke do tareeke dikhati hain. Asexual reproduction mein sirf ek parent hota hai, aur uske young lagbhag uski perfect copies hote hain. Sexual reproduction mein do parents mein se har ek aadha genetic material deta hai, isliye har offspring ek naya mixture hota hai.

Is chapter mein tum dekhoge ki dono tareeke microbes, plants aur animals mein, aur aakhir mein human beings mein kaise kaam karte hain. Tum yeh bhi dekhoge ki sexual reproduction se bane chhote-chhote differences kisi species ke survival ke liye itne important kyun hain.

11.1 Asexual Reproduction

Kai organisms bina partner ke reproduce karte hain. Ek bacterium ya Amoeba bas do mein toot jaata hai. Ek yeast cell bahar ek bud nikaalta hai. Simple many-celled animals, jaise Hydra aur sponges, apne hi body se poore naye animals bana sakte hain. Inmein se kuch se tum pichhli classes mein mil chuke ho. Plants is kaam mein khaas taur par achhe hain.

Haldi (हल्दी) ka plant khod kar dekho, to tumhe ek moti, gaanthon wali underground stem milegi jise rhizome kehte hain. Har gaanth se leaves aur roots nikal sakti hain, isliye kisan seeds ki jagah rhizome ke tukde lagaate hain. Kitchen ke kisi andhere kone mein bhooli hui pyaaz ki bulb se hari leaves nikal aati hain. Geeli mitti par giri Bryophyllum ki patti (पत्थरचट्टा, patharchatta) ke kinare ke notches se chhote plantlets ug aate hain (Fig. 11.1). Har baar parent ki root, stem ya leaf se naya plant ugta hai. Isme koi flower ya seed shaamil nahi hota. Ise vegetative propagation kehte hain.

Isme sirf ek parent hota hai, aur naya plant parent ki apni cells se banta hai. Isliye naya plant genetically parent jaisa hi hota hai: parent mein jo bhi features the, naye plant mein bhi hote hain.

11.1.1 Plants mein vegetative propagation agriculture mein kaise madad karta hai?

Maan lo Ratnagiri ke paas ek kisan ke paas aam ka ek ped hai jiska fruit bahut meetha hai. Agar woh uska seed boti hai, to seedling do parents se aata hai, kyunki flower ko aas-paas ke kisi bhi aam ke ped se pollen mil sakta hai. Uska fruit kaafi alag ho sakta hai, aur fruit aane mein saat-aath saal lag sakte hain. Agar woh ped ko hi copy karti hai, to har naye ped mein bilkul wahi genetic material hota hai, woh wahi meetha fruit deta hai, aur aam taur par teen se paanch saal mein fruit dene lagta hai.

Gardeners, kisanon aur scientists ne is natural ability ko chaar soche-samjhe methods mein badal diya hai (Fig. 11.2):

• Cutting: kuch buds wala stem ka ek tukda geeli mitti mein lagaya jaata hai aur usmein apni roots aa jaati hain. Roses, hibiscus aur sugarcane aise hi ugaye jaate hain.
• Layering: ek neechi, lachili branch ko parent se jude rehte hue hi mitti mein daba kar pin kiya jaata hai. Dabe hue hisse par roots banne ke baad branch ko kaat kar alag kar diya jaata hai. Jasmine aur bougainvillea ki aksar layering ki jaati hai.
• Grafting: jo variety tumhe chahiye uska shoot (scion) ek mazboot variety ke roots wale plant (stock) se joda jaata hai. Dono jud kar ek plant ban jaate hain jo scion ka fruit deta hai. Aam, amrood aur roses ki aam taur par grafting ki jaati hai.
• Tissue culture: shoot tip ki kuch cells ko ek sterile jar mein nutrients wali jelly par ugaya jaata hai. Woh badh kar ek mass banati hain jisse saikdon chhote plantlets bante hain.

In methods se growers ek saabit variety ke bahut saare plants, sab ek hi quality ke, jaldi aur bina seeds ka intezaar kiye bana sakte hain. Yeh un plants ke liye bhi kaam karte hain jo bahut kam ya bilkul seeds nahi banate, jaise hum jo kele khaate hain. Isiliye India ke itne saare orchards, nurseries aur sugarcane ke khet seedlings ki jagah copies se lagaye jaate hain.

Sirf plants hi khud ko copy nahi karte. Do aur organisms school microscope mein aasaani se dekhe ja sakte hain: yeast aur bread mould.

Hand lens se dekho to talaabon aur jheelon ke ek chhote animal, achhe se khaaye hue Hydra par aksar ek chhoti side branch hoti hai jiske apne chhote tentacles hote hain. Yeast ke ubhaaron ki tarah yeh ek bud hai, aur is tarah young banane ko budding kehte hain. Bud wahan shuru hota hai jahan parent ki ek jagah ki cells divide hoti rehti hain. Hydra mein isme ek mouth aur tentacles ka ek ring ban jaata hai, phir yeh toot kar apne aap jeeta hai; yeast mein ubhaar ko ek nucleus milta hai aur woh nayi cell ban kar alag ho jaata hai (Fig. 11.3).

Moulds organisms ka ek aur group hai jo asexually reproduce karta hai. Fruit basket ke peechhe bhoola hua santra, theek se band na kiya gaya achaar ka jar, ek din purana pav ka tukda: jahan bhi khaana geela ho aur yun hi pada rahe, wahan moulds aa jaate hain. Woh kahin se bhi achaanak nahi aate. Woh hawa mein tairti chhoti-chhoti cells se ugte hain, jaise Activity 11.3 mein tum khud check kar sakte ho.

Apni drawing phir se dekho. Mould ek fungus hai jiski body barik threads, yaani hyphae, ki ek chatai jaisi hoti hai. Kuch threads upar ki taraf ugte hain aur tip par phool jaate hain. Bread mould (Rhizopus) mein har phooli hui tip spores se bhara ek gol sac hai; Aspergillus, jo ek aam hara ya kaala mould hai, usmein spores ki chains ek gol head par baithi hoti hain (Fig. 11.4). Mould ka ek chhota patch laakhon spores kyun banata hai? Kyunki lagbhag sab bekaar ho jaate hain. Spore cell ka ek chhota sa kan hai jise halki si hawa bhi utha sakti hai, aur jahan bhi woh girta hai, bas intezaar hi kar sakta hai. Sookhi deewar par woh inactive pada rehta hai; geeli bread ya pake amrood par woh jaldi hi nayi hyphae nikaal deta hai.

Yeast bud, mould spore, Hydra bud aur roots wali hibiscus cutting mein kya common hai? Har ek poori tarah mitosis se banta hai. Is tarah ke cell division mein cell pehle apne chromosomes copy karti hai aur phir unhe barabar baant deti hai, isliye do daughter cells mein se har ek ko bilkul wahi set milta hai jo parent cell ka tha. Isliye sirf mitosis se bani offspring genetically apne parent jaisi hoti hain; woh clones hoti hain.

Asexual reproduction tez hota hai aur ismein partner ki zaroorat nahi hoti, isliye jab khaana aur garmi bharpoor hon to population bahut tezi se badh sakti hai: ek yeast cell ek din mein hazaaron ban sakti hai. Iski kamzori yeh hai ki saari copies ki strengths bhi same hoti hain aur kamzoriyan bhi same.

11.2 Sexual Reproduction

Sexual reproduction mein naya individual tab shuru hota hai jab do special cells, har parent se ek, fuse hoti hain. Har parent naye individual ka aadha genetic material deta hai. Isse ek puzzle banta hai. Human body cell mein 46 chromosomes hote hain. Agar bachche ko maa se saare 46 aur baap se saare 46 milte, to uske 92 hote. Uske bachchon ke 184 hote, aur generation dar generation yeh number doguna hota jaata. Aisa nahi hota, kyunki fuse hone wali cells ek special division se banti hain jo pehle number ko aadha kar deta hai. Yeh division meiosis hai.

11.2.1 Sexual reproduction mein variations banane mein meiosis kaise madad karta hai?

Tumhari genetic information chromosomes mein store hoti hai; yeh har cell ke nucleus mein dhaage jaisi bodies hain. Kutte ki body cell mein inhe gino to 78 milenge; garden pea mein 14; human mein 46. Human ke 46 asal mein 23 matched pairs hain: har pair ka ek member maa ke egg se aaya aur doosra baap ke sperm se.

Biologists yahan do words use karte hain. Body cell, jismein har pair ke dono members hote hain, diploid (double) hoti hai. Jis cell mein har pair ka sirf ek member ho, woh haploid (single) hoti hai. Meiosis ek diploid cell ko haploid cells mein badalta hai, aur yahi gametes hain: male animals mein sperm aur female animals mein eggs. Flowering plants bhi gametes banate hain: male gametes pollen grains ke andar safar karte hain, aur egg flower mein ek ovule ke andar intezaar karta hai. Gamete ka ek hi kaam hai, doosre parent ke gamete se fuse hona. Humans mein har sperm aur har egg mein 23 chromosomes hote hain, aur unse bani cell mein phir se 46 ho jaate hain (Fig. 11.5).

Meiosis sirf number aadha nahi karta. Pair ka kaun sa chromosome kisi khaas gamete mein jaayega, yeh chance ki baat hai, aur yeh har pair ke liye alag se tay hota hai. Ek sperm ko chromosome 1 ki maa wali copy aur chromosome 2 ki baap wali copy mil sakti hai; agle ko ulta mil sakta hai. Ek insaan kitne alag-alag gametes bana sakta hai?

Isi shuffling ki wajah se same parents ke do bachche kabhi har tarah se ek jaise nahi hote, jab tak woh identical twins na hon, jo ek hi zygote se aate hain. Ek species ke individuals ke beech ke differences ko variations kehte hain, aur yeh uske survival ke liye bahut zaroori hain. Jab sookha, koi nayi bimaari ya climate mein change aata hai, to ho sakta hai kuch individuals mein features ka aisa combination ho jo unhe survive aur reproduce karne mein madad kare. Unki offspring ko yeh mil jaata hai, aur kai generations mein species badal jaati hai. Is dheemi badlaav ko evolution kehte hain. Jaise, seed se ugaye gaye wheat ke khet mein aksar kuch plants hote hain jo rust fungus ki ek nayi kism ko resist karte hain, aur plant breeders bilkul aise hi plants ikattha karte hain.

11.2.2 Flowering plants mein sexual reproduction

Tumhare aas-paas ke zyadatar plants, playground ki ghaas se le kar sadak kinare ke bargad tak, ek bahut bade group ke hain: flowering plants, yaani angiosperms, jinki lagbhag teen lakh known species hain. Inke liye flower sexual reproduction ka organ hai. Pine jaise cone wale plants bina flowers ke sexually reproduce karte hain; agla chapter unpar wapas aayega.

Hibiscus ki ek kali aur ek khila hua hibiscus flower lo. Kali ke bahar kas kar lipte hue hare, patti jaise flaps hain, yeh sepals hain. Kali badhte waqt yeh andar ke naazuk parts ko bachate hain. Flower khilne par uski badi rangeen petals dikhti hain. Unka colour, aur kai flowers mein khushboo aur meetha nectar, insects aur birds ko flower ki taraf kheenchte hain. Aur andar dekho to tumhe do aur tarah ke parts milte hain (Fig. 11.7).

Hibiscus jaisa flower, jismein chaaron whorls hon, complete flower hota hai; kuch flowers mein parts jude hote hain, jaise sadabahar ki petals ek patli tube banati hain. Centre se shuru karo, pistil se, jo female part hai. Iska phoola hua base, ovary, ek ya zyada ovules rakhta hai, aur har ovule mein ek egg cell hoti hai, jo female gamete hai. Ovary se ek dandi, style, upar uthti hai aur stigma par khatam hoti hai, jo aksar chipchipa, baalon wala ya pankh jaisa hota hai taaki pollen grains us par chipak jaayein. Pistil ke charon taraf stamens khade hote hain, jo male parts hain. Har ek ek anther hai, ek chhoti thaili jo male gametes wale pollen grains banati hai, aur ek patle filament par tiki hoti hai.

Flower ko fruit banne ke liye anther ka pollen stigma tak pahunchna zaroori hai. Kya tum dikha sakte ho ki yeh transfer sach mein zaroori hai?

11.2.3 Flowers mein pollination ka process kaise hota hai?

Pollen do tareekon se stigma tak pahunch sakta hai (Fig. 11.8). Self-pollination mein pollen usi flower ke stigma par ya usi plant ke kisi doosre flower par girta hai, isliye dono parents asal mein ek hi plant hote hain. Cross-pollination mein pollen usi kism ke kisi doosre plant ke flower tak le jaaya jaata hai. Cross-pollination do plants ke genetic material ko milata hai, isliye zyada varied seeds deta hai. Kisi doosri kism ke plant ka pollen aam taur par kuch nahi karta: aam ka stigma amrood ke pollen ko ignore kar deta hai.

Pollination ke bina seeds nahi bante, aur aam taur par fruit bhi nahi. Jis kaddu ki bel par koi madhumakkhi nahi aati, woh ek bhi kaddu banaye bina apne female flowers gira deti hai.

11.2.4 Pollination strategies aur reproductive success

Plants chal kar ek doosre ke paas nahi ja sakte, isliye woh pollen le jaane walon par depend karte hain, jinhe pollinators kehte hain: wind, water, insects aur birds, aur bats bhi. Flower ki shape, colour aur pollen uske carrier ke hisaab se hote hain, jaise Table 11.7 dikhata hai.

11.2.5 Fertilisation aur seed formation

Stigma par girna sirf shuruaat hai. Aage jo hota hai woh pistil ke andar chhupa hota hai (Fig. 11.9):

1. Pollen grain stigma se paani aur sugar sokhta hai aur ek patli pollen tube bahar nikaalta hai.
2. Tube style ke andar se neeche surang banati hai, jaise root mitti mein raasta banati hai, aur ek ovule mein ghus jaati hai.
3. Ek male gamete tube se neeche khisakta hai aur ovule mein egg cell se fuse ho jaata hai. Male aur female gamete ke is milan ko fertilisation kehte hain.
4. Fuse hui cell, yaani zygote, mein phir se poore chromosome pairs hote hain. Yeh kai baar divide hokar embryo ban jaati hai, jo chhoti si root aur shoot wala ek miniature plant hai.

Flowers murjhaane ke ek hafte baad pea plant ko dekho (Fig. 11.10). Petals aur stamens gir chuke hain, lekin ovary khinch kar hari pod ban gayi hai. Andar har fertilised ovule ek seed ban gaya hai: seed coat mein lipta ek embryo aur food store. Pod khud, yaani paki hui ovary, fruit hai. Baingan aur amrood mein purane sepals fruit se jude rehte hain.

Fruit ka kaam apne seeds ko parent plant se door pahunchana hai, chahe hawa se, paani se ya use khaane wale kisi animal ke andar. Jo seed sahi temperature par geeli mitti tak pahunchta hai, woh ankurit (germinate) hokar seedling ban jaata hai. Kyunki koi do seeds bilkul ek hi pair ke gametes se nahi aate, seedlings thode alag hote hain, aur conditions badalne par isse species ko zyada mauke milte hain.

11.3 Animals mein Sexual Reproduction

Kuch animals asexually reproduce kar sakte hain, jaise tumne Hydra mein budding dekhi. Lekin zyadatar animals sexually reproduce karte hain, aur unki pehli challenge hai sperm aur egg ko milana. Iske do solutions hain (Fig. 11.11).

Frogs aur zyadatar fish paani mein breed karte hain. Jab female apne eggs deti hai, male un par apne sperm chhidak deta hai, aur gametes paani mein hi milte hain: yeh external fertilisation hai. Yeh sirf paani mein kaam karta hai, jahan sperm tair kar eggs tak pahunch sakte hain, aur ismein bahut barbaadi hoti hai. Dhaarein eggs ko baha le jaati hain, fish aur insects unhe kha jaate hain, aur kai tak koi sperm pahunchta hi nahi. Isliye yeh animals bahut zyada sankhya mein eggs banate hain.

Reptiles, birds aur mammals zameen par breed karte hain, jahan sperm ek animal se doosre tak tair kar nahi ja sakte. Male sperm ko female ki body mein pahunchata hai aur eggs uske andar fertilise hote hain: yeh internal fertilisation hai. Uske baad young ki hifaazat hoti hai, reptiles aur birds mein ek mazboot shell se, ya mammals mein maa ki apni body se. Inmein se kahin zyada bachte hain, isliye kam eggs chahiye hote hain.

11.4 Animals mein Reproduction ki Variations

Table 11.9 dekho to ek trade-off dikhta hai: jo animals sabse zyada eggs banate hain, woh unka sabse kam dhyaan rakhte hain, aur sabse zyada khote hain.

Eggs banane mein khaana kharch hota hai. Hazaaron eggs dene wala frog ya fish har egg mein zyada yolk nahi bhar sakta; yolk egg mein khaane ka store hai. Isliye uske eggs jaldi phoot kar chhote, simple larvae ban jaate hain jinka main kaam khaana hai. Tadpole algae charta hai, caterpillar pattiyan chabata hai, aur housefly ka maggot sadte kachre par palta hai. Jab larva kaafi khaana jama kar leta hai, to uski body adult form mein dobara banti hai; is badlaav ko metamorphosis kehte hain (Fig. 11.12).

Reptiles aur birds kam eggs dete hain, lekin har egg mein itna yolk hota hai ki embryo ko tab tak khaana mile jab tak woh adult ka chhota roop ban kar bahar na aa jaaye. Mammals mein embryo maa ki body ke andar badhta hai aur maa hi use khaana deti hai.

Hen ke chooze ko dekho, jo nikalne ke kuch ghanton baad daane chugne lagta hai, aur kabootar ke bachche ko, jo andha aur ganja nikalta hai aur dono parents hafton use khilaate hain. Saare mammals apne young ko doodh pilaate hain, kuch kuch hafton tak aur kuch, jaise haathi, saalon tak. Moti baat yeh hai ki jo young apna zyada development egg ya maa ke andar karte hain, woh bahar aakar khud ko sambhalne ke liye zyada taiyaar hote hain.

11.5 Human Beings mein Reproduction

Humans sexually reproduce karte hain, internal fertilisation ke saath, aur baby apni maa ke andar badhta hai, doosre mammals ki tarah. Yahan tum is mein shaamil organs ke baare mein jaanoge, sperm aur egg ko unke banne ki jagah se milne ki jagah tak follow karoge, aur dekhoge ki baby kaise develop hota hai. Tum yeh bhi dekhoge ki life ke is hisse ko healthy aur safe kaise rakhein.

11.5.1 Reproductive maturity

Pichhli classes mein tumne padha tha ki adolescents body aur feelings mein kitne tareekon se badalte hain. In badlaavon mein se ek yeh hai ki boys mein testes aur girls mein ovaries active ho jaati hain aur gametes banana shuru karti hain: sperm aur eggs. Jis stage par yeh shuru hota hai use puberty kehte hain. Iski koi fixed date nahi hoti. Yeh lagbhag 8 se 14 saal ki umar ke beech kabhi bhi shuru ho sakti hai, aur har insaan ki timing us insaan ke liye normal hai.

Female body ke andar sperm aur egg fuse hokar zygote bana sakte hain. Zygote uterus mein badh kar embryo ban jaata hai. Uske main organs ban jaane ke baad develop hote baby ko foetus kehte hain.

11.5.2 Male reproductive system ke parts kya hain?

Sperm human body ki sabse chhoti cells mein se ek hai. Microscope mein yeh ek chhote tadpole jaisa dikhta hai: baap ke genetic material se bhara oval head, aur chaabuk jaisi tail jo use aage dhakelti hai. Male reproductive system aisi cells bahut badi sankhya mein banata hai aur unhe female body mein pahunchata hai (Fig. 11.13).

Sperm do testes (singular: testis) ke andar bante hain. Important organs ke liye ajeeb baat hai ki testes abdomen ke bahar, skin ki ek thaili, scrotum, ke andar latakte hain. Iska reason temperature hai: sperm sirf normal body temperature se lagbhag 2–3 °C kam par hi theek se develop hote hain. Testes glands bhi hain. Woh hormone testosterone chhodte hain (hormone ek chemical messenger hai jise blood le jaata hai), jo sperm production ko chalu rakhta hai aur boys mein puberty ke changes laata hai, jaise bhaari aawaaz aur chehre par baal.

Ab ek sperm ko body ke bahar tak follow karo. Woh testis se ek lambi tube, vas deferens, ke zariye nikalta hai, jo ghoom kar abdomen mein upar jaati hai. Bladder ke paas do tarah ki glands, seminal vesicles aur prostate gland, ek fluid daalti hain jo sperm ko khaana deta hai aur unhe tairne deta hai. Phir vas deferens urethra se jud jaati hai, jo penis se hokar jaane wali tube hai. Urethra baaki time urine le jaati hai, lekin urine aur sperm kabhi ek saath nahi.

11.5.3 Female reproductive system ke parts kya hain?

Egg ke raaste ko trace karo to tum female system ke har part se miloge (Fig. 11.14). Yeh do ovaries mein se ek mein shuru hota hai; ovaries abdomen mein neeche badaam jaise shape ke organs hain jo eggs store karte hain. Ovaries female hormones bhi chhodti hain, jaise oestrogen, jo girls mein puberty ke changes laate hain. Chhoda gaya egg oviduct (fallopian tube) ke funnel jaise end mein kheench liya jaata hai aur usmein aage badh kar uterus tak jaata hai; uterus lagbhag mutthi ke size ka ek khokhla, muscular organ hai jiski andar ki lining naram hoti hai, aur yahin baby develop hota hai. Uterus ki patli neechi gardan, cervix, vagina mein khulti hai, jo body ke bahar tak jaane wala ek muscular raasta hai.

11.5.4 Reproductive cells kaise bante hain?

Sperm aur eggs dono gametes hain, phir bhi dono ek doosre se bilkul alag hain (Table 11.10). Ek aadmi ke testes roz laakhon chhote, tairne wale sperm banate hain. Ek aurat ki ovaries aam taur par mahine mein ek hi egg chhodti hain, lekin woh kahin bada hota hai aur embryo ke pehle dinon ke liye khaane ki supply ke saath aata hai. Yeh pattern, bahut saare chhote chalne wale male gametes aur kam bade ruke hue female gametes, animal kingdom ke zyadatar hisse mein dikhta hai.

Dono kisme meiosis se banti hain, jo Section 11.2.1 ka halving division hai, aur gametes banane ko gametogenesis kehte hain. Isliye har sperm aur har egg mein 23 chromosomes hote hain, aur unse bane zygote mein normal human body cell jaise 46 hote hain.

11.5.5 Jab sperm egg se milta hai, to kya hota hai?

Ek ladki apne saare eggs ke saath hi paida hoti hai, lagbhag 10 se 20 lakh immature eggs, aur baad mein koi naya egg nahi banati. Puberty se aage, lagbhag mahine mein ek baar, ek ya doosri ovary mein ek egg pakta hai aur chhoda jaata hai. Us egg ko follow karo (Fig. 11.15):

1. Ovulation. Paka egg ovary se phoot kar bahar aata hai aur oviduct mein kheench liya jaata hai. Uterus pehle hi apni lining moti karna shuru kar chuka hota hai, jaise kisi mehmaan ka intezaar ho. Egg ke is release ko ovulation kehte hain.
2. Milan. Sexual intercourse ke baad vagina mein pahunche sperm tair kar uterus se hote hue upar jaate hain. Laakhon mein se sirf kuch sau hi oviducts tak pahunchte hain. Agar wahan egg ho, to ek sperm usmein ghus sakta hai aur unke nuclei fuse ho jaate hain: yeh fertilisation hai, aur humans mein yeh oviduct mein hota hai.
3. Safar. Zygote uterus ki taraf dheere-dheere badhte hue mitosis se baar-baar divide hota hai, aur cells ki ek chhoti si ball ban jaata hai.
4. Implantation. Fertilisation ke lagbhag ek hafte baad cells ki ball uterus tak pahunchti hai, jismein ab ek moti, naram, blood se bhari layer hoti hai, aur usmein dhans jaati hai. Yeh implantation hai, aur pregnancy isi pal shuru hoti hai.

11.5.6 Jab egg fertilise nahi hota, to kya hota hai?

Zyadatar mahino mein koi sperm nahi pahunchta, aur unfertilised egg toot jaane se pehle sirf lagbhag ek din zinda rehta hai. Uterus ki moti, blood se bhari lining, jo embryo ke swaagat ke liye bani thi, phir kisi kaam ki nahi rehti aur woh bhi toot jaati hai. Agle 3 se 7 dinon mein purani lining kuch blood ke saath vagina se bahar nikal jaati hai: yeh menstruation hai, jise aam taur par period kehte hain. Isi beech nayi lining banne lagti hai, ek aur egg pakne lagta hai, aur cycle phir se shuru hota hai (Fig. 11.16).

Yeh menstrual cycle aam taur par har 21 se 35 din mein repeat hota hai; 28 din ek common average hai, aur bahut kam log bilkul regular hote hain. Periods aam taur par lagbhag 10 se 14 saal ki umar ke beech shuru hote hain aur menopause par rukte hain, jo aam taur par lagbhag 45 se 55 ke beech hota hai. Cycle ka din 1 period ka pehla din hai. Ovulation agla period shuru hone se lagbhag 14 din pehle hota hai, isliye 28-day cycle mein yeh lagbhag din 14 par aata hai, lekin 32-day cycle mein lagbhag din 18 par.

11.5.7 Pregnancy aur childbirth

Human pregnancy lagbhag nau mahine chalti hai, yaani aakhri period ke pehle din se gine to lagbhag 40 hafte. Doctors ise lagbhag teen-teen mahine ke teen trimesters mein baant-te hain (Fig. 11.18).

• Pehla trimester (mahine 1–3). Lagbhag chhah hafton ke andar heart dhadakna shuru kar deta hai, aur brain, spine aur doosre bade organs banne lagte hain, zyadatar pehle do mahino mein. Lagbhag week 9 se badhte baby ko foetus kehte hain.
• Doosra trimester (mahine 4–6). Foetus tezi se badhta hai. Lagbhag paanchve mahine mein maa aam taur par use hilta hua mehsoos karne lagti hai.
• Teesra trimester (mahine 7–9). Foetus ka weight tezi se badhta hai, uske lungs mature hote hain, aur woh aam taur par sir neeche karke ghoom jaata hai, janm ke liye taiyaar.

Is poore samay uterus foetus ko panaah deta hai, aur maa ki body uska khaana aur oxygen deti hai. Janm shuru hone par uterus ki muscular wall baar-baar zor se sikudti hai aur baby ko cervix aur vagina, yaani birth canal, se bahar dhakel deti hai. Agar normal birth se maa ya baby ko khatra ho, to doctors caesarean section naam ke operation se baby ki delivery kar sakte hain.

• Pehla doodh. Breastfeeding janm ke ek ghante ke andar shuru ho jaani chahiye. Pehle chhah mahine sirf maa ka doodh hi baby ko saara khaana aur paani deta hai, aur antibodies bhi jo use infections se bachati hain.
• Garmi aur pyaar bhari dekhbhaal. Newborns jaldi garmi kho dete hain; maa se skin-to-skin contact unhe garam rakhne mein madad karta hai.
• Time par vaccines. Pehle vaccines janm par diye jaate hain, aur baaki vaccination card ki dates ke hisaab se lagte hain.
• Maa ki dekhbhaal. Janm se recover hone mein hafte lagte hain. Use achha khaana, aaraam aur ghar par madad chahiye, aur use tobacco, alcohol aur bina doctor ki salaah wali medicines se door rehna chahiye, jo uske doodh se baby tak pahunch sakti hain.

11.5.8 Pregnancy ke dauraan maa ki health

Anaemia, yaani blood mein bahut kam iron, India mein pregnant women mein aam hai, aur isse baby janm ke time chhota aur kamzor ho sakta hai. Isliye pregnant woman ko iron, protein, calcium aur folic acid se bharpoor khaana chahiye, jaise hari pattedaar sabziyan, daalein, doodh aur eggs, aur doctors use iron aur folic-acid tablets bhi dete hain. Health centre par kai check-ups (kam se kam chaar ki salaah di jaati hai) problems ko jaldi pakad lete hain, aur uska doctor batata hai ki kitna aaraam aur halki exercise uske liye theek hai. Chinta aur akelapan bhi health par asar daalte hain, isliye jo family kaam baant-ti hai aur uski baat sunti hai, woh maa aur baby dono ko theek rakhne mein madad karti hai.

11.5.9 Sexually mature hone ka kya matlab hai?

14 saal ki umar mein koi itna lamba ho sakta hai ki car ke pedals tak pair pahunch jaayein, lekin iska matlab yeh nahi ki woh shehar ke traffic mein gaadi chalane ko taiyaar hai. Sexual maturation bhi aisa hi hai. Adolescence mein body dheere-dheere reproduce karne layak ban jaati hai, jab boys sperm banana shuru karte hain aur girls ke menstrual cycles shuru hote hain. Uske baad jo aa sakta hai, jaise relationship, pregnancy, bachcha, uske liye taiyaari emotional maturity par depend karti hai, aur woh dheere badhti hai, late teens aur usse aage tak. Yeh dikhti hai is baat mein ki koi insaan tez feelings ko kaise sambhalta hai, pressure ko na kehta hai, baat karke cheezein suljhaata hai aur kuch karne se pehle nateejon ko tolta hai.

11.5.10 Unwanted pregnancies aur infections ko kaise roka ja sakta hai?

Sexual activity ke saath do risks aate hain: infections aur unplanned pregnancy. Knowledge aur zimmedaar choices dono ko rok sakte hain.

Kuch infections sexual contact se ek insaan se doosre mein jaate hain. Inhe sexually transmitted infections (STIs) kehte hain. Inmein bacteria se hone wale gonorrhoea aur syphilis, aur viruses se hone wale genital herpes, genital warts aur HIV shaamil hain. HIV body ki suraksha ko kamzor karta hai aur, treatment na ho to, AIDS tak le jaata hai. Bacterial STIs medicines se theek ho sakte hain, lekin HIV samet kuch viral STIs abhi theek nahi ho sakte, sirf control kiye ja sakte hain. Condom ek barrier banata hai jo STI failne ka risk bahut kam kar deta hai, aur pregnancy bhi rokta hai.

Pregnancy rokne wale methods ko contraception kehte hain. Yeh alag-alag tareekon se kaam karte hain (Table 11.11).

Medical procedure se pregnancy khatam karne ko abortion (law mein, medical termination of pregnancy) kehte hain. Yeh pregnancy mein jaldi, aam taur par pehle trimester ke andar, sabse safe hota hai, aur India mein yeh sirf law dwara tay conditions mein aur sirf trained doctors dwara hi allowed hai.

Kuch families ne medical scans ka galat use karke pata kiya ki paida hone wala baby ladki hai, aur phir pregnancy khatam kar di. Is tarah ke sex-selective abortion ki wajah se India ke kuch hisson mein ladkon se kam ladkiyan reh gayi hain. Ise rokne ke liye law (1994 ka PC-PNDT Act) paida hone wale baby ka sex batane par rok lagata hai. Ek nyaaypoorn aur healthy society ke liye balanced sex ratio zaroori hai, aur har ladki ko paida hone ka barabar haq hai.