Hujayra, sokht, vazifa va tarkibi on

Sokhti hujayra. Ba monandi digar mavjudoti zinda badani odam niz az hujayraho iborat ast. Hujayraho dar bayni moddahoi baynihujayravi joy giriftaand. In moddaho hamchun manbai gizo ustuvorii ujayrahoro tamin mekunand. Hujayraho shaklu andozayu amaliyoti gunogun dorand, vale az jihati sokht ba hamdigar monandand. Har yak hujayra az jild, sitoplazma va yadro (hasta) iborat ast.

Jildi hujayra bo parda pushida shuda, az yakchand qabat molekulaho iborat ast va tabiati lipidi (charbi) dorad. Jildi nimguzaronandai hujayra moddahoro ba tavri intikhobi meguzaronad.

Sitoplazma muhiti nimmoei dokhili hujayra meboshad. Dar on organoidhoi hujayra az qabili yadro, yadrocha, ribosomaho, lizosomaho, mitokhondriyaho, kompleksi Golji, turi endoplazmatiki, markazi hujayra va parda joygirand.

Har yak organoid vazifai muayyanro ba jo meorad. Masalan, mitokhondriya manbai nerui hujayra ast, ribosoma baroi hosilkunii safeda khizmat merasonad. YAdro manbai asosii taqsimshavii hujayra ast. Dar dokhili yadro nakhhoi rishtamonand — khromosomaho mavjudand. Miqdori khromosomahoi odam dar yadroi hujayra 23 juftand. Onho manbai asosii mavodi irci meboshand.

Tarkibi khimiyavii hujayra. Hujayra az payvastagihoi gunoguni khimiyavi iborat ast, ki onho ba du guruh judo meshavand:

1) payvastagihoi organiki;

2) payvastagihoi gayriorganiki.

Payvastagihoi organikii hujayra. Pesh az hama ba in guruh safedaho, charbho, karbogidratho va kislotahoi nukleini dokhil meshavand. In payvastagiho baroi ijroishi in yo on vazifa naqshi kalon mebozand.

Safedaho — moddai asosi va khele murakkabi har yak hujayraand. Dar molekulaashon payvastagihoi gayriorganiki sadho va hazorho marotiba kalon meboshad. Safedaho sarchashmai hayotand.

Baze safedahoe hastand, ki reaksiyahoi kimiyoviro tezonida, vazifai katalizatorro ijro mekunand, onhoro ferment menomand.

CHarbho va karbogidratho «masolehi binokori»-i hujayra buda, baroi faoliyati hayotii organizm hamchun manbai neru khizmat mekunad.

Kislotahoi nukleini dar yadroi hujayra hosil meshavad. Nomi kislotaho az kalimai lotini (nukleus — yadro) girifta shudaast.

Payvastagihoi gayriorganikii hujayra. Ba in payvastagiho ob va namakhoi minerali dokhil meshavand. Miqdori ob dar hujayra az hama ziyodtar buda, qarib 80%-ro tashkil va dar hama ravandhoi hayot ishtirok mekunad. Moddahoi gizoii mahlul az moddai baynihujayravi iborat buda, ba vositai parda ba hujayra dokhil meshavand. Ob inchunin baroi az hujayra khorij shudani moddahoe, ki dar natijai reaksiyahoi khimiyavi ba vujud meoyand, musoidat mekunad. Namakhoi minerali dar sitoplazma na on qadar ziyod buda, dar hayoti hujayra naqshi kalon mebozand. Ba in namakho kaliy (K+), kalsiy (Ca+), natriy (Na+), magniy (Mg+) va gayraho dokhil meshavand.

Savolho:

1. Kadom organoidhoi hujayraro medoned?
2. Dar hujayrahoi odam chandto khromasoma mavjud ast?
3. Dar hujayra kadom moddahoi organiki va gayriorganiki mavjudand?

Hosiyati hayotii hujayra

Mubodilai moddaho khosiyati asosii hayotii hujayra meboshad. Dar hujayra moddahoi gizoi bo muntazam oksigen vorid gashta, mahsuloti tajziya judo meshavad. In moddaho dar ravandi biokhimiyavi ishtirok namuda, hosilshavii safedaho, charbho, karbogidratho va payvastagihoi onhoro, ki az moddahoi sodda iboratand, tamin menamoyad. Moddahoi hosilshuda ba hujayrahoi muayyani organizm khosand. Misol, dar mushakho safedaho tajziya shuda, kashishkhurii onhoro tamin menamoyand. Dar barobari tajziyai biologi dar hujayraho payvastagihoi uzvi ba amal omada, tarkibi moddahoi murakkab soddatar megardad.

Qarib hamai reaksiyai tajziya bo ishtiroki gazi oksigen, ob va khorijshavii neru ba amal meoyad. Nerui hosilshuda baroi hujayra lozim ast. Baroi hujayra sabzish va afzoish khos meboshad. Dar natijai taqsimshavi az yak hujayrai modari du hujayrai dukhtari hosil meshavad. Onho inkishof meyoband va chun hujayrai modari kalon meshavand. Hujayraho az yakchand soat to dahho,  sadho soat umr mebinand. Hujayrahoi zinda omilhoi fiziki va khimiyaviro his mekunand. Onhoro qobiliyati mutaassirshavi (hayajonpaziri) menomand. Hujayra dar zeri tasiri omilhoi beruna ba angezish meoyad. Dar on surati sintezi biologi, tajziyai moddaho, talabot ba oksigen va harorat tagyir meyobad. Hamin tavr hujayraho vazifai muayyani khudro ijro mekunand.

Misol: hujayrai gadudho mahsuli gunogun judo menamoyad. Hujayrahoi mushak kashish mekhurad. Dar hujayrai asab akhbori dokhilshuda pahn meshavad. 

Muhiti dokhilii organizm. Bisyorii hujayrahoi badan bo muhiti beruna aloqamand nestand. Faoliyati hayotii onhoro muhiti dokhili tamin mekunad. In muhit az se moe:

baynihujayravi, khun va moei limfa iborat ast. In moddaho az yak taraf hujayraro bo mavodi baroi hayot zarur tamin kunad, az tarafi digar mahsuli tajziya az hujayra khorij megardad. Tarkib va khosiyati fizikiyu kimiyovii in moddaho dar hujayra nisbatan doimiand va in holati mutadili kori hujayraro tamin menamoyad.

Savolho

1. Hosiyati asosii hayotii hujayra kadomhoyand?
2. Muhiti dokhilii organizm chist?
3. Ba muhiti dokhili kadom moddaho dokhil meshavand?