RNA Polymerase I is responsible for transcribing the large ribosomal RNAs (28S, 18S, and 5.8S rRNA).
Question 182 of 668
📘 CLASS XII
In eukaryotes, RNA Polymerase III transcribes?
RNA Polymerase III transcribes tRNA, 5S rRNA, and snRNAs. Mnemonic: I-rRNA, II-mRNA, III-tRNA.
Question 183 of 668
📘 CLASS XII
The precursor of mRNA in eukaryotes is called?
Heterogeneous nuclear RNA (hnRNA) is the primary transcript in eukaryotes that undergoes processing (splicing, capping, tailing) to become mature mRNA.
Question 184 of 668
📘 CLASS XII
The process of removing introns and joining exons is called?
Splicing is the post-transcriptional process where non-coding introns are removed and coding exons are joined to form a continuous coding sequence.
Question 185 of 668
📘 CLASS XII
Which structure is responsible for splicing of hnRNA?
The spliceosome is a large complex of snRNAs and proteins that catalyzes the removal of introns from the primary RNA transcript.
Question 186 of 668
📘 CLASS XII
Capping involves the addition of which nucleotide to the 5-prime end of hnRNA?
A 7-methylguanosine cap is added to the 5-prime end of the transcript. This protects the RNA and aids in ribosome binding.
Question 187 of 668
📘 CLASS XII
Polyadenylation (tailing) occurs at which end of the eukaryotic mRNA?
A poly-A tail consisting of 200-300 adenylate residues is added to the 3-prime end of the mRNA, increasing stability and facilitating transport.
Question 188 of 668
📘 CLASS XII
How many codons constitute the genetic code?
There are 64 possible triplet codons formed from the 4 nitrogenous bases (4^3 = 64).
Question 189 of 668
📘 CLASS XII
Which of the following codons functions as a Start Codon?
AUG acts as the start codon (coding for Methionine) which initiates translation.
Question 190 of 668
📘 CLASS XII
The property that a single amino acid is coded by more than one codon is called?
Degeneracy refers to the redundancy in the genetic code, where most amino acids are specified by more than one codon.
