Mene ne kwafi a ilmin halitta? Wannan lokaci gina jiki kira

Tsari a Biology - Multi-mataki tsari na karanta bayanai daga DNA, wanda yake shi ne bijiro da batun kafa na gina jiki biosynthesis a cikin cell. Nucleic acid ne m kayyade bayanai a cikin jiki, don haka yana da muhimmanci a decipher shi da kuma canja wurin zuwa wasu salon salula Tsarin domin kara tattaro peptides.

Kalmar "kwafi a nazarin halittun"

Gina jiki kira ne mai babbar m tsari a cikin wani cell na jiki. Ba tare da halittar peptide kwayoyin ba zai iya kula da al'ada rayuwa, t. Don wadannan kwayoyin mahadi suna da hannu a duk tafiyar matakai na rayuwa, ne tsarin da aka gyara na da yawa tsokoki da kuma gabobin da wasa a gudãnar siginar da wani m rawa a cikin jiki.

A tsari, wanda ta fara da gina jiki biosynthesis, ne kwafi. Biology a takaice ya raba shi a cikin matakai uku:

1. Qaddamarwa.
2. Elongation (kara sarkar RNA).
3. Ƙarshe.

Tsari a Biology - shi ne mai stepwise cascade halayen wanda haifar da DNA template hada RNA kwayoyin. Kuma kamar haka ne kafa ba kawai bayanai ribonucleic acid, amma kuma kai, ribosomal, kananan makaman nukiliya da sauransu.

Kamar yadda da wani biochemical tsari, kwafi dogara a kan al'amurra da dama. Da farko, suna enzymes cewa bambanta a prokaryotes da eukaryotes. Wadannan musamman sunadarai taimaka fara da gudanar da wani kwafi halayen daidai, wanda shi ne muhimmin domin samun high quality-furotin fitarwa.

kwafi na prokaryotes

Tun trankriptsiya ilmin halitta - shi ne da kira na RNA a kan wani DNA template, a cikin wannan tsari, yafi enzyme ne a DNA-RNA dogara polymerase. A kwayoyin cuta, akwai daya kawai irin polymerases ga duk kwayoyin na ribonucleic acid.

RNA polymerase bisa ga ka'ida na complementarity kammala RNA tufka ta amfani da samfuri DNA sarkar. A cikin abun da ke ciki na wannan enzyme yana da biyu β-subunits, daya α-subunit da daya σ-subunit. A farko biyu aka gyara aiki a matsayin enzyme jiki samuwar, da kuma sauran biyu suna alhakin riƙewa na enzyme ga jigidar halittar DNA da fitarwa na kiran kasuwa rabo daga deoxyribonucleic acid, bi da bi.

Ba zato ba tsammani, sigma factor ne daya daga cikin filaye a kan wanda gane wani musamman gene. Alal misali, Latin harafi σ index N yana nufin cewa RNA polymerase gane genes da suke kunshe da wani rashi na nitrogen a cikin yanayi.

Traskriptsiya a eukaryotes

Ba kamar kwayoyin cuta, dabbobi da kuma shuke-shuke kwafi na faruwa mafi rikitarwa. Da farko, a cikin kowane cell akwai ba daya amma uku daban-daban na RNA polymerases. Daga cikin su:

1. RNA polymerase I. Shi ne ke da alhakin kwafi na ribosomal RNA kwayoyin halittu (ba domin 5s ribosomal RNA subedinitsv).
2. RNA polymerase II. Its manufa shi ne haduwa da al'ada bayanai (matrix) ribonucleic acid, wanda aka sa'an nan da hannu a watsa shirye-shirye.
3. RNA polymerase III. The aiki na da irin wannan polymerases ne haduwa ribonucleic acid kai, da kuma 5s-ribosomal RNA.

Abu na biyu, domin amincewa da wani mai kiran kasuwa a eukaryotic Kwayoyin nedostachno da kawai polymerase. A qaddamarwa na kwafi ma hannu na musamman peptides, kira TF-sunadarai. Kawai tare da su via wani RNA polymerase iya daukar farkon DNA kira da RNA kwayoyin.

Meaning of kwafi

The RNA kwayoyin da aka kafa a kan wani DNA template, baya a haɗe zuwa ribosomes inda aka karanta tare da bayanai da kuma hada gina jiki. Kan aiwatar da samuwar peptide da muhimmanci ga Kwayoyin, kamar yadda ba tare da wadannan kwayoyin mahadi ba zai iya zama al'ada rayuwa: su ne da farko tushen ga mafi muhimmanci enzymes daga biochemical halayen.

Kwafi a ilmin halitta - shi ne kuma tushen rRNA, wanda wani bangare ne na ribosome da tRNA, wanda suna da hannu a cikin kai da amino acid din a lokacin fassarar wadannan ba membrane Tsarin. Suna iya ma za a hada snRNA (kananan nukiliya), wanda aiki kunshi a splicing na RNA kwayoyin.

ƙarshe

Translation da kwafi a ilmin halitta taka muhimmiyar rawa a cikin kira na gina jiki. Wadannan matakai ne babban bangaren na tsakiyar akidarsu na ilmin sanin kwayoyin halittu, wanda ya furta cewa DNA matrix da aka hada ta hanyar RNA, kuma RNA, bi da bi, shi ne dalilin farko da samuwar sunadaran.

Ba tare da kwafi shi ba zai yiwu ba don karanta bayanai da aka cure ne a triplets na deoxyribonucleic acid. Wannan ya tabbatar da sake muhimmancin aiwatar a nazarin halittu matakin. Duk wani cell, ko prokaryotic ko eukaryotic, dole ne ci gaba da haduwa sabon kwayoyin da sabon gina jiki, wanda suke bukata a wannan lokacin domin ya raya rai. Saboda haka, kwafi a ilmin halitta - shi ne babban mataki a cikin aikin kowane mutum cell a cikin jiki.