Nā nīnau hoʻohālike e pili ana i ka DNA a me nā Genes
Pendahuluan
I loko o ke olaola molekala, ʻo ka DNA (Deoxyribonucleic Acid) a me nā genes nā manaʻo nui e pili ana i ka hoʻomaopopo ʻana i ka hoʻoilina o nā ʻano a me ka hana o nā meaola ola. ʻO ka DNA kahi mole e mālama ana i nā ʻike genetic āpau e pono ai e hoʻoponopono i ke ʻano a me ka hana o kahi meaola. ʻO nā genes, ma ka ʻaoʻao ʻē aʻe, he mau ʻāpana o ka DNA e code no nā protein kikoʻī a i ʻole RNA. He mea nui ka hoʻomaopopo ʻana i ka DNA a me nā genes no kekahi mea hoihoi i ka biology, biotechnology, lāʻau lapaʻau, a me nā kahua pili. E kūkākūkā kēia ʻatikala i kekahi mau nīnau i nīnau pinepine ʻia e pili ana i kēia mau kumuhana, me kā lākou wehewehe ʻana.
1. Nīnau 1: ʻAno o ka DNA
Nīnau: E wehewehe i ke ʻano helix pālua o ka DNA a e inoa i nā ʻāpana nui e hana ana iā ia.
Kūkākūkā: He helix pālua ka DNA, ʻo ia hoʻi, he ʻelua kaula i wahī ʻia kekahi i kekahi, e like me ke alapiʻi wili. Ua hāpai mua ʻia kēia ʻano e James Watson lāua ʻo Francis Crick i ka makahiki 1953, nāna hoʻi i lanakila i ka Nobel Prize no kā lāua ʻike ʻana. Hana ʻia ka DNA me ʻekolu mau ʻāpana nui: phosphate, deoxyribose sugar, a me nā kumu nitrogenous. ʻO kēia mau kumu nitrogenous ʻo adenine (A), thymine (T), cytosine (C), a me guanine (G). I loko o ka helix pālua, hui pū kēia mau kumu: A hui me T ma o ʻelua mau pilina hydrogen, a hui pū ʻo C me G ma o ʻekolu mau pilina hydrogen. Hōʻike ʻia nā kaula o ke alapiʻi DNA e ke kō a me ka phosphate, ʻoiai ʻo nā ʻanuʻu e hōʻike ʻia e nā hui kumu.
2. Nīnau 2: Hoʻopili hou ʻana o ka DNA
Nīnau: He aha ke ʻano o ka hana hou ʻana o ka DNA semiconservative, a no ke aha he mea nui?
Kūkākūkā: ʻO ka hana hou ʻana o ka DNA Semiconservative kahi hana e loaʻa ai i kēlā me kēia molekole DNA hou kekahi kaula mua a me kekahi kaula hou. Ke hana hou ka DNA, wehe ʻia ka helix pālua e like me ka zipper, a lawelawe kēlā me kēia kaula mua ma ke ʻano he template no ka hana ʻana o kahi kaula hou. He mea nui kēia hana no ka mea e hōʻoiaʻiʻo ana e loaʻa i kēlā me kēia cell kaikamahine kahi kaula hoʻokahi o ka DNA e like me ke kaula mua, e mālama ana i ka pono o ka ʻike genetic ma o nā hanauna. Kōkua ka hana hou ʻana o Semiconservative i ka hōʻemi ʻana i nā hewa i ka wā o ka mahele ʻana o ke kelepona a he mea nui ia no ka hoʻoilina genetic pololei.
3. Nīnau 3: Ka Hōʻike ʻana o nā Gene
Nīnau: Pehea e hana ʻia ai nā kaʻina hana transcription a me ka unuhi ʻana i ka hōʻike ʻana o ka gene?
Kūkākūkā: ʻElua mau pae nui o ka hōʻike ʻana o ka gene: ka transcription a me ka unuhi ʻana. I ka transcription, hoʻohana ʻia kahi ʻāpana o ka DNA i loaʻa kahi gene kikoʻī ma ke ʻano he template e hana i ka messenger RNA (mRNA). Hana ʻia kēia kaʻina hana i loko o ka nucleus cell a pili i ka enzyme RNA polymerase, ka mea e hoʻopaʻa ai i ka DNA a hōʻuluʻulu i ka mRNA ma muli o ke kaʻina kumu DNA. Ma hope o ka transcription, haʻalele ka mRNA i ka nucleus a hele i nā ribosomes i loko o ka cytoplasm, kahi e hana ʻia ai ka unuhi ʻana.
I ka wā o ka unuhi ʻana, heluhelu nā ribosomes i ke kaʻina kumu mRNA ma nā hui o ʻekolu i kapa ʻia he codons. He kikoʻī kēlā me kēia codon no kahi waikawa amino kikoʻī. Lawe ka RNA hoʻoili (tRNA) i nā waikawa amino e pili ana i ka ribosome, a laila hoʻākoakoa iā lākou i loko o kahi kaulahao polypeptide e pili ana i ke kaʻina codon. Ke pau ke kaulahao polypeptide, hana hou ʻia ia e lilo i protein hana e pāʻani ana i kahi kuleana koʻikoʻi i loko o ke kelepona.
4. Nīnau 4: Hoʻololi Hoʻoilina
Nīnau: He aha ke ʻano o ka mutation genetic, a pehea e hiki ai i nā mutations ke hoʻopilikia i nā meaola?
Kūkākūkā: ʻO nā hoʻololi genetic he mau loli i ke kaʻina kumu o ka DNA. Hiki i kēia mau loli ke hana koke i ka wā o ka hana hou ʻana o ka DNA a i ʻole e hoʻoulu ʻia e nā kumu o waho e like me ka radiation a me nā kemika mutagenic. Hiki i nā hoʻololi ke hoʻopilikia i nā meaola ma nā ʻano like ʻole, ma muli o ke ʻano a me kahi o ka loli.
Hiki ke hoʻokaʻawale ʻia nā Mutations i ʻekolu mau ʻano nui:
– Nā hoʻololi kiko: pili i nā loli i loko o hoʻokahi nucleotide. Hiki i kēia mau mea ke hana ma ke ʻano o nā pani (ke pani ʻana i hoʻokahi kumu me kekahi), nā hoʻokomo, a i ʻole nā holoi ʻana.
– Ka hoʻololi ʻana o ka missense: hopena i ka hoʻololi ʻana o hoʻokahi waikawa amino i loko o kahi protein.
– Nā hoʻololi lapuwale: hana i nā codons hoʻōki mua, e hoʻōki ana i ka synthesis protein i ka wā mua.
– Nā hoʻololi Frameshift: i hana ʻia e nā hoʻokomo a i ʻole nā holoi ʻana e hoʻololi i ke kiʻina heluhelu mRNA.
Hiki ke ʻokoʻa ka hopena o nā mutations. ʻAʻohe hopena o kekahi mau mutations (nā mutations leo ʻole), aʻo kekahi e hiki ke hoʻopilikia i ka hana protein, hoʻoulu i nā maʻi genetic, a i ʻole, i nā hihia kakaikahi, hāʻawi i kahi pono evolutionary.
5. Nīnau 5: Hoʻohana ʻana o ka Biotechnology a me ka DNA Recombinant
Nīnau: E wehewehe pehea e hiki ai ke hoʻohana ʻia ka ʻenehana DNA recombinant i ka hoʻomohala ʻana i nā mea kanu kūpaʻa i nā mea ʻino.
Kūkākūkā: ʻO ka ʻenehana DNA Recombinant e pili ana i ka hoʻohui ʻana i nā genes mai nā meaola like ʻole e hana i nā meaola me nā ʻano hou a makemake ʻia. I ka hoʻomohala ʻana i nā mea kanu kū i nā mea ʻino, hiki ke lawe ʻia nā genes e hoʻopili ana i nā protein e pepehi i nā pepeke a i ʻole e kāohi i ko lākou ulu ʻana mai nā bacteria a hoʻokomo ʻia i loko o ka genome mea kanu.
Eia kekahi laʻana, ʻo Bacillus thuringiensis (Bt) kahi bacteria e hana ana i kahi protein i ʻawahia i kekahi mau pepeke. Hiki ke hoʻokaʻawale ʻia ka gene e hoʻopili ana i ka protein Bt a hoʻokomo ʻia i loko o ka DNA mea kanu me ka hoʻohana ʻana i ka ʻenehana DNA recombinant. ʻO ka hua Bt hopena e hana i kāna protein ponoʻī a hiki ke pale iā ia iho mai nā hoʻouka kaua pepeke me ka ʻole o ka pono no nā pesticides kemika hou aʻe. ʻAʻole wale kēia e hoʻonui i ka huahana o nā mea kanu akā e hōʻemi pū i ka hopena o ke kaiapuni o ka hoʻohana ʻana i nā pesticides.
Pani
ʻAʻole wale ka hoʻomaopopo ʻana i ka DNA a me nā genes he mea nui no ka poʻe e hana ana i ka biology a me ka lāʻau lapaʻau, akā no ka lehulehu hoʻi, no kona pili ʻana i ka biotechnology a me ko kākou ola o kēlā me kēia lā. Ma ka nānā ʻana i nā pilikia hoʻohālike a me nā kūkākūkā, ke manaʻolana nei mākou e hāʻawi kēia i ka ʻike hohonu i kēia kumuhana koʻikoʻi. Mahalo no kou hahai ʻana mai, a ke manaʻolana nei mākou ua kōkua kēia.
