Gịnị ka a gụnyere ná DNA sugar? Chemical bases nke DNA Ọdịdị

Olee otú ịtụnanya na-ekiri otú yiri onye ọ bụla ọzọ bụ nne na nna na ụmụ. Ma ọ bụ, na Kama nke ahụ, dị nnọọ iche si na, na ụmụnna, na site na mama na papa. Gịnị mere o mee na ihe ọ na-adabere na ya? Gịnị owuwu na-ahụ maka ichebe, igba, nyefee na ngosipụta nke mgbaàmà na ụmụ nne na nna ha?

Na ọrụ bụ nke nucleic asịd na-etolite chromosomes. Na ha bụ ndị ụmụ irighiri ihe na-arụ ọrụ nke niile usoro metụtara si n'aka ruo n'aka na mgbanwe. Special ruuru a bụ DNA ụmụ irighiri.

History nke chọpụtara nucleic asịd

N'ihi na a ogologo oge banyere ihe ndị a na ụmụ irighiri ihe a na-amaghị. Otú ọ dị, na 1869, a ọkà mmụta sayensị si research Miescher hụrụ a ngwakọta nke DNA na RNA, na mgbe ahụ bụ ike igosi na ha na iso asịd. O mere nke a site n'ịmụ mkpụrụ ndụ ọbara ọcha na abu.

Ebe ọ bụ na mgbe ahụ malitere kpụ ọkụ n'ọnụ ọmụmụ ndị a ogige. Ọtụtụ ndị ọkà mmụta sayensị na-agbalị iji chọpụta chemical mejupụtara nke DNA na RNA. Iji ghọta ha ọdịdị, Ọdịdị na ọdịdị nke ndu ọrụ. A oké onyinye a mere ndị dị otú ahụ dị ka:

• A. N. Belozersky.
• Thomas Morgan.
• K. Bridges.
• A. Meller.
• G. de Vries.
• A. Sturtevant.
• G. A. Nadson.
• A. S. Serebrovsky.
• NP Dubinin.
• TS Filippov na ndị ọzọ.

Na site na 1900 ka taa ọ ghọta ọdịdị nke nucleic asịd, chemical bases nke DNA Ọdịdị, ya atụmatụ na ndu mkpa. nchọpụta e mere, ka anyị tụlee nke a molekul eluigwe na ala ndabere nke ihe niile dị ndụ.

Research na ubi nke mkpụrụ ndụ ihe nketa-ekwe ka mmekọrịta dị n'etiti DNA na genome chromosomes, ghọta mkpụrụ ndụ ihe nketa koodu nke ọtụtụ ndụ e kere eke. Ọ dị mkpa maka nghọta nke anụ ọhịa unit, ya na-arụ ọrụ usoro.

Ọzọkwa, chemical mejupụtara nke chromosome e kwuru. Ọ hụrụ na ndabere nke - a nucleic acid molekul enwe a kpọmkwem Ọdịdị.

DNA: general e ji mara

Full transcript afo aha - deoxyribonucleic acid. Yana a RNA acid na-ezo aka a ọnụ ọgụgụ nke nucleic. Natara aha ya n'ihi na nke DNA abatakwa sugar. Ya aha - deoxyribose.

The chemical mejupụtara nke DNA na RNA ndị yiri nnọọ, ihe dị iche dị ka oge isi na carbohydrate akpụ molekul. Na RNA bụ ribose.

Ke ofụri ofụri, deoxyribonucleic acid molekul bụ a abụọ tọrọ atọ mgbagwoju macromolecule enwe a molekụla arọ nke nnukwu na iche iche mejupụtara. Ya mere, ọtụtụ n'ime ndị na ogige nke graphic image nwere ụdị abụọ uzo, ihe jikọtara transverse nzọụkwụ - agbụ.

Na 1953, Chargaff na ibe ya na-enwe ike n'ụzọ zuru ezu na-ekpughe esịtidem Ọdịdị na mejupụtara nke molekul, nke bụ nke dị oké mkpa maka dum nke molekụla bayoloji na sayensị n'ozuzu. Ọ bịara doo anya na na ise-carbon sugar gụnyere DNA bases (pentose), purine na pyrimidine ndọkwasi nile na orthophosphoric acid residues.

Ọ bụ omume ọ bụghị naanị ka n'ihu ghọta nnọọ Ọdịdị nke ahụ compound, ma na-amụ Njirimara, anụ ahụ na chemical. The ndu ọrụ na uru maka organism e ẹmende dị ka a isi, eluigwe na ala na kpọmkwem maka nke ọ bụla umi.

chemical mejupụtara

Ọ bụrụ na e ji mara ndị dị n'ime atọm na molekụla mejupụtara nke nucleic acid ụmụ irighiri ihe, ọ bụ ike ime ka a mata ọtụtụ isi ụdị nke ogige:

• pentose - deoxyribose (carbohydrate bụ a monosaccharide);
• organic bases - purine (ebe adenin na Gwanine) pyrimidine (agakọta na tamin);
• phosphoric acid residues na free agbụ.

Nke a, n'ozuzu, ihe niile chemical bases nke DNA Ọdịdị. Ihe ọzọ bụ na a Nchikota a niile mmiri na-adịghị mfe, ma ọ bụ a mgbagwoju na pụrụ iche usoro. N'ihi ya, interconnected deoxyribose, isi na inorganic acid fọduru ọnụ na-etolite a nucleotide. Ọ bụ otu n'ime ndị nucleotide usoro, ma na-amalite dum Ọdịdị nke molekul dị ka a dum.

Unique bụ usoro nke na-organic isi ga-emi odude otu n'azụ ndị ọzọ na na mmekọrita n'akụkụ yinye. The nucleotide usoro e wuru dị ka ụkpụrụ ụfọdụ, isi n'etiti nke bụ complementarity (echesinụ ime purine na pyrimidine mmiri). Nke a na-enye ohere ọ bụla mmadụ nwere ya mkpụrụ ndụ ihe nketa koodu, a pụrụ iche, ebum pụta ụwa na miri-kpọmkwem.

Phenotype egosipụta n'ụdị a inwe nke kpamkpam dị iche iche e ji mara, na nke na-enweghị abụọ yiri ndị mmadụ (ma e wezụga ejima ndị yiri ibe), onye pụrụ iche na atụmatụ nke anya.

Ọdịdị nke DNA na-agụnye ọ bụla sugar?

Ndabere nke ọ bụla organic okwu - a carbon yinye atọm. The DNA molekul bụghị isịneke. Mgbe niile nke DNA abatakwa sugar, ya bụ, ọ bụ a usoro nke ise carbon atọm, jikọtara na a cyclic Ọdịdị. Nke a otu molekul na-etre site ihe oxygen akwa n'ime n'ozuzu okirikiri.

The chemical mejupụtara nke sugar na-kwupụtara na-esonụ ahụrụ anya usoro: C ₅ H ₁₀ O _4. Nke a molekul - aldopentoza gụnyere ise carbon atọm, gbagọrọ n'ime a akaghị. Ke adianade do, otu n'ime atọm na yinye kama nke hydroxyl otu naanị nwere hydrogen, ya mere e nwere a nganiihu dị ka "deoxy" na sugar aha, i.e., na-enweghị oxygen.

The chemical mejupụtara nke sugar chọpụtara na-amụ Fibusom Lieven, onye meghere dum Ọdịdị na chemical ọdịdị nke compound na 1929.

Base na molekul

Organic bases na-akụkụ nke DNA nucleic acid nwere ike kewara abụọ isi iche iche.

1. Purine - mgbagwoju owuwu kpụrụ abụọ nke carbon okirikiri - a ise-membered na isii membered. A na-agụnye ebe adenin na Gwanine, nke na-arụkọ ka a pyrimidine isi esịnede deoxyribonucleic acid.
2. Pyrimidine - isii membered carbon yiri mgbaaka. Nke a na-agụnye agakọtakwa na-agakọta.

N'ihi ya, ọ na-egosi na otu akụkụ nke DNA sugar na a isi jikọọ ọ bụla ọzọ na ejikọrọ na njikọ na buu nke phosphoric acid. All ọnụ ọ na-enyo nucleotide. The n'ozuzu Ọdịdị nke abụọ-tọrọ atọ DNA molekul nucleotides kee n'etiti onwe ha dị ka a na-achị nke complementarity: ebe adenin isi kwekọrọ agakọtakwa, Gwanine na - agakọta.

Ụdị nkekọ dị n'etiti ahụ

The isi ụdị nke mmekọrịta dị n'etiti akụrụngwa DNA owuwu dị ka ndị a:

• hydrogen;
• pola covalent;
• intermolecular agha nke agakarị;
• Vahan der Waals mmekọrịta.

Nke a-enye gị ohere abụọ-tọrọ atọ Ọdịdị adị atọ conformations:

• isi - linear usoro nke nucleotides;
• abụọ - ọ bụla helically gbagọrọ yarns na abụọ na-esote onye ọ bụla ọzọ;
• tertiary - mgbagwoju conformational globule ike na helical molekul.

N'ihi ya, eziokwu ahụ bụ na a akụkụ nke DNA abatakwa sugar, isi, na acid residues bụ ihe ndabere nke ya Ọdịdị na ala maka mmejuputa iwu a ọnụ ọgụgụ nke interactions na guzobere chemical agbụ.

DNA uru maka ntule

E nwere ọtụtụ ihe dị mkpa isi:

1. Ụmụ irighiri atụle asịd na-gụnyere ke chemical mejupụtara nke chromosomes na-ekpebi njirimara nke ihe niile dị ndụ ntule.
2. DNA - ndabere nke njikọ nke mgbagwoju polypeptide ígwè maka nzuzo na nnyefe nke butere n'aka àgwà.
3. Deoxyribonucleic acid - isi n'ihi transcription, i.e. isi RNA njikọ, protein ekemende.

Ndị dị otú ahụ Filiks ekem ke niile ntule. Nke a na-enye ohere nke a Ọdịdị akpọ eluigwe na ala unit nke ihe nile dị ndụ.

imepụtaghachi ụmụ irighiri

Usoro a na-anọchi anya a ibawanye nke DNA molekul, aa spontaneously na mmefu nke ike na ndu eme ntule. The isi akụrụngwa na nke a - DNA polymerase, enzyme catalyzing na ịchịkwa dum njikọ.

Replication-ekwu bụ na onye ọ bụla nke uzo nke molekul ekewa ma okpukpu abụọ ya linear usoro. Ihe usoro na-arụpụta abụọ ọhụrụ DNA ụmụ irighiri ọ bụla nke nwere otu polypeptide yinye agadi, ma a abụọ kpamkpam ọhụrụ, wuru dị ka ụkpụrụ nke complementarity.

Usoro Uru - inye ụmụ mkpụrụ ndụ ihe nketa ọmụma n'ozuzu ya.