Molecular Basis Of Inheritance

In eukaryotes, the functionalization of mRNA from heterogeneous nuclear RNA (hnRNA) involves several processes. These include:5' End Capping: The addition of a cap to the 5' end of the RNA molecule, which protects the RNA from degradation and assists in ribosome binding during translation.Polyadenylation: The addition of a poly(A) tail to the 3' end of the RNA molecule, which similarly aids in protection from enzymatic degradation and facilitates export from the nucleus and translation.Splicing: The removal of introns (non-coding regions) from the RNA transcript and joining of exons (coding regions), resulting in a continuous sequence that codes for a specific protein.On the other hand,amino acylationrefers to the process where amino acids are activated and attached to their corresponding transfer RNAs (tRNAs) using ATP. This is an essential step for translation, as it prepares tRNAs for protein synthesis, but it is not part of mRNA processing in eukaryotes.

During translation, when a ribosome encounters a stop codon in the mRNA sequence, a release factor binds to this stop codon. This binding prompts the ribosome to release the newly formed polypeptide chain from the tRNA. Consequently, the ribosome disassembles, effectively ending the translation process.

To transcribe the DNA template into RNA, follow these steps:Write the template strand 3′→5′ (RNA is built 5′→3′):DNA template (5′→3′): GTCTAGGCTTCTC⇒ template (3′→5′): C T C T T C G G A T C T GApply base‐pairing rules:$ $Transcribe 3′→5′ template into 5′→3′ RNA:template 3′→5′: C T C T T C G G A T C T GRNA 5′→3′: G A G A A G C C U A G A CSo the mRNA is5′–GAGAAGCCUAGAC–3′That matches Option A.

Step 1. Identify theanticodonon the tRNAGiven anticodon: Step 2. Find the complementarycodonon the mRNAAnticodon and codon base-pairantiparallel(complementary 3′–5′ to 5′–3′).So let’s write the anticodon in the3′→5′direction (since codons are written 5′→3′): Now, the complementary codon on the mRNA (5′→3′) will be: Step 3. Determine which amino acid corresponds to mRNA codon5′–AAC–3′From the standard genetic code: ✅Answer:The tRNA with anticodon5′–GUU–3′carriesAsparagine.Correct Option: A. Asparagine (codon AAC)

The correct answer is:✅Option D:A group of viruses with RNA genome and reverse transcriptase activityExplanation:Retroviruses are RNA viruses that carry an enzyme calledreverse transcriptase, which converts their RNA genome into DNA once inside a host cell. This DNA then integrates into the host genome, allowing the virus to replicate as part of the host’s genetic material.Example:Human Immunodeficiency Virus (HIV) is a well-known retrovirus.