ameeba

ameeba (Amoeba) jeevavaijnyaaanik vargeekaran mein ek vansh hai tatha is vansh ke sadasyon ko bhi praay: ameeba kaha jaata hai. atyant saral prakaar ka ek prajeev (protojoaa) hai jiski adhikaansh jaatiyaaain nadiyon, taalaabon, meethe paani ki jheelon, pokharon, paani ke gaddhon aadi mein pai jaati hain. kuchh sambandhit jaatiyaaain mahattvapoorn parajeevi aur rogakaari hain.

jeevit ameeba bahut sookshm praani hai, yadyapi iski kuchh jaatiyon ke sadasya 1/2 mi.mi. se adhik vyaas ke ho sakte hain. sanrachana mein yeh jeevaras (protoplaajm) ke chhote dher jaisa hota hai, jiska aakaar nirantar dheere-dheere badalta rahata hai. koshikaaras baahar ki or atyant sookshm koshaakala (plaajmaalema) ke aavaran se surakshit rahata hai. swayam koshaaras ke do spasht star pahachaane ja sakte hain-baahar ki or ka svachh, kanarahit, kaaainch jaisa, gaadha baahya ras tatha uske bheetar ka adhik taral, dhoosarit, kanayukt bhaag jise aantar ras kehte hain. aantar ras mein hi ek bada keindrak bhi hota hai. sampoorn aantar ras anek chhoti badi annadhaaniyon tatha ek ya do sankochi rasadhaaniyon se bhara hota hai. pratyek annadhaani mein bhojanapadaarth tatha kuchh taral padaarth hota hai. inke bheetar hi paachan ki kriya hoti hai. sankochirsadhaani mein keval taral padaarth hota hai. iska nirmaan ek chhoti dhaani ke roop mein hota hai, kintu dheere-dheere yeh badhti hai aur ant mein fat jaati hai tatha iska taral baahar nikal jaata hai.

ameeba ki chalanakriya badi rochak hai. iske shareer ke kuchh asthaayi pravardh nikalte hain jinko kootapaad (nakali pair) kehte hain. pehle chalan ki disha mein ek kootapaad niklata hai, fir usi kootapaad mein dheere-dheere sabhi koshaaras bahakar sama jaata hai. iske baad hi, ya saath saath, naya kootapaad banane lagta hai. haaiman, maast aadi ke anusaar kootapaadon ka nirmaan koshaaras mein kuchh bhautik parivrtanon ke kaaran hota hai. shareer ke pichhle bhaag mein koshaaras gaadhe godan ki avastha (jail sthiti) se taral sthiti mein parivrtit hota hai aur iske vipreet agale bhaag mein taral sthiti se jail sthiti mein. adhik gaadha hone ke kaaran aage bananevaala jail koshikaaras ko apni or kheenchata hai.

ameeba ke pramukh bhaag - 1. sankochi rasadhaani (contractive vacuole); 2. annadhaani (food vacuole); 3. kootapaad (pseudopod); 4. aantar ras (Endoplasm); 5. svachh baahya ras (Ectoplasm); 6. keindrak (nucleus)

ameeba jeevit praaniyon ki tarah apna bhojan grahan karta hai. vah har prakaar ke kaarbanik kanon-jeevit athva nirjeev-ka bhakshan karta hai. in bhojanakanon ko vah kai kootapaadon se gher leta hai; fir kootapaadon ke ek doosare se mil jaane se bhojan ka kan kuchh taral ke saath annadhaani ke roop mein koshaaras mein pahuainch jaata hai. koshaaras se annadhaani mein pehle aaml, fir kshaareeya paachak yooshon ka sraav hota hai, jisse proteen to nishchaya hi pach jaate hain. kuchh logon ke anusaar mand (staarch) tatha vasa ka paachan bhi kuchh jaatiyon mein

hota hai. paachan ke baad pachit bhojan ka shoshan ho jaata hai aur apaachya bhaag chalanakriya ke beech kramash: shareer ke pichhle bhaag mein pahuainchata hai aur fir usaka parityaag ho jaata hai. parityaag ke liye koi vishesh ang naheen hota.

shvasan tatha utsarjan (malatyaag) ki kriyaaeain ameeba ke baahm tal par praaya: sabhi sthaanon par hoti hain. inke liye vishesh angon ki aavayakata isliye naheen hoti ki shareer bahut sookshm aur paani se ghira hota hai.

koshikaaras ki rasaakarshan daab (osamotik preshar) baahar ke jal ki apeksha adhik hone ke kaaran jal baraabar koshaakala ko paar karta hua koshaaras mein jama hota hai. iske falasvaroop shareer foolakar ant mein fat ja sakta hai. at: jal ka yeh aadhikya ek do chhoti dhaaniyon mein ekatr hota hai. yeh dhaani dheere-dheere badhti jaati hai tatha ek seema tak badh jaane par fat jaati hai aur saara jal nikal jaata hai. iseeliye isko sankochi dhaani kehte hain. is prakaar ameeba mein rasaakarshan niytrann hota hai.

prajanan ke pehle ameeba golaakaar ho jaata hai, iska keindrak do keindrakon mein baint jaata hai aur fir jeevaras bhi beech se khinchakar baint jaata hai. is prakaar ek ameeba se vibhaajan dvaara do chhote ameebe ban jaate hain. sampoorn kriya ek ghante se kam mein hi poorn ho jaati hai.

pratikool ritu aane ke pehle ameeba annadhaaniyon aur sankochi dhaani ka parityaag kar deta hai aur uske chaaron or ek kathin puti (sist) ka aaveshtan taiyaar ho jaata hai jiske bheetar vah garami ya sardi mein surakshit rahata hai. paani sookh jaane par bhi puti ke bheetar ka ameeba jeevit bana rahata hai. haaain, is beech usaki sabhi jeevanakriyaaeain lagbhag naheen ke baraabar rahati hain. is sthiti ko bahudha sthagit praanikram kehte hain. ubalata paani daalne par bhi puti ke bheetar ka ameeba marata naheen. bahudha puti ke bheetar anukool ritu aane par koshaaras tatha keindrak ka vibhaajan ho jaata hai aur jab puti nasht hoti hai to usamein se do ya chaar nanhein ameebe nikalte hain.

manushya ki aaintadi mein chhah prakaar ke ameebe rah sakte hain. unamein se ek ke kaaran pravaahika (pechish) utpann hoti hai jise ameebaajanya pravaahika kehte hain. yeh ameeba aaintadi ke oopari star ko chhedakar bheetar ghus jaata hai. is prakaar aaintadi mein ghaav ho jaate hain. kabhi kabhi ye ameebe yakrut (livr) tak pahuainch jaate hain aur vahaaain ghaav kar dete hain.