Molecular Basis of Inheritance
Transcription
Transcription matlab cell ka ek gene ko DNA se RNA ke strand me copy karna. Isi tarah gene ke instructions safe DNA se nikal kar ek working message ban jaate hain.
Enzyme RNA polymerase gene ki shuruaat par bind karta hai, DNA ka thoda hissa unwind karta hai, aur ek strand padhta hai. Wo base pairing se RNA copy banata hai, par ek badlav ke saath: RNA thymine (T) ki jagah uracil (U) use karta hai, to U ko A ke saath pair karta hai.
Ready messenger RNA gene ka message ribosomes tak le jaata hai, jahaan use padh kar protein banta hai. DNA ka sirf ek strand padha jaata hai, jise template strand kehte hain.
Yahaan students galti karte hain
Sirf ek DNA strand template ki tarah padha jaata hai, dono nahi. Aur RNA T ki jagah U use karta hai. Students aksar DNA ko letter-for-letter copy karte hain aur T se U swap bhool jaate hain, ya dono strands ek saath padhne lagte hain. Ek strand, aur uske har A par RNA me U aata hai.
Yaad rakho
Ek gene, ek strand padha, T banta hai U. Yahi transcription hai.
Exam me kaise kaam aata hai: template versus coding strand, aur U-for-T rule classic traps hain.
Ye kahaan jud'ta hai
Yahaan bana RNA ant nahi hai. Wo ribosome tak jaakar protein me padha jaata hai, to transcription aur translation ek hi flow ke do hisse hain: DNA se RNA se protein.
Agla step: translation →Ek quick check
Transcription ke dauraan DNA template ke adenine (A) ke saath pair karne wala RNA base hai:
- AThymine (T)
- BUracil (U)
- CGuanine (G)
- DCytosine (C)