CBSE 2024 · Region 4 · Set 1 · Q30 · 4 marks
Generally, in eukaryotic cells the average length of a transcription unit along a DNA molecule is about $\displaystyle 8,000$ nucleotides, so the RNA product of the transcription is also that long. But it only takes about $\displaystyle 1200$ nucleotides from the above RNA product to translate average sized polypeptide of $\displaystyle 400$ Amino acids.(a)Name this RNA product transcribed from the DNA that subsequently translates into a polypeptide of $\displaystyle 400$ amino acids. Mention the enzyme responsible for transcribing this type of RNA from the DNA.(b)Name and explain the process the RNA molecule transcribed from $\displaystyle 8000$ nucleotide long DNA undergoes to be able to translate a polypeptide of $\displaystyle 400$ amino acids.Write the number of RNA polymerases involved in the transcription of DNA in a prokaryote and eukaryotes.Mention the difference in the site of transcription in a prokaryote and eukaryote cell.
Generally, in eukaryotic cells the average length of a transcription unit along a DNA molecule is about $\displaystyle 8,000$ nucleotides, so the RNA product of the transcription is also that long. But it only takes about $\displaystyle 1200$ nucleotides from the above RNA product to translate average sized polypeptide of $\displaystyle 400$ Amino acids.
(a)
Name this RNA product transcribed from the DNA that subsequently translates into a polypeptide of $\displaystyle 400$ amino acids. Mention the enzyme responsible for transcribing this type of RNA from the DNA.
(b)
Name and explain the process the RNA molecule transcribed from $\displaystyle 8000$ nucleotide long DNA undergoes to be able to translate a polypeptide of $\displaystyle 400$ amino acids.
Write the number of RNA polymerases involved in the transcription of DNA in a prokaryote and eukaryotes.
Mention the difference in the site of transcription in a prokaryote and eukaryote cell.
Marking-scheme solution
(a)
•
hnRNA/ heterogeneous nuclear RNA
•
RNA polymerase II
(b)
hnRNA undergo capping at $\displaystyle 5$’ end (methyl guanosine triphosphate/mGppp), and tailing at $\displaystyle 3$’ end (with poly A tail or adenylate residue), further splicing is carried out, where non coding sequences or introns are removed and coding sequence or exons are joined together/ diagrammatic representation with given markers can also be considered.
•
In prokaryotes - $\displaystyle 1$
•
In eukaryotes-$\displaystyle 3$
In prokaryotes the transcription takes place in the cytoplasm/cytosol
whereas in Eukaryote transcription occurs in the Nucleus
Molecular Basis of InheritanceTranscriptionUnderstandcase_studymedium
More from Molecular Basis of Inheritance
- Explain how the addition of lactose in the medium regulates the switching on of the lac operon in bacteria.2025 · asked 3×
- The type of bond represented by the dotted line '-----' in a schematic polynucleotide chain is:2024 · asked 3×
- Which of the options has correct identification of 'P', 'Q' and 'R' in the illustration of 'Central Dogma'…2024 · asked 3×
- Study the diagram given below and answer the questions that follows: Identify the structure shown in the…2025 · asked 3×
- What is a genetic code? Why did scientists feel the need to propose a genetic code? Genetic code is said to…2026 · asked 3×
- Assertion: Primary transcripts in eukaryotes are subjected to splicing to remove the introns. Reason (R):…2024 · asked 3×
- Given below is a heterogeneous RNA formed during Eukaryotic transcription: How many introns and exons…2025 · asked 3×
- Consider the given data of a hypothetical small portion of mRNA that codes for a functional polypeptide chain…2024 · asked 3×
CBSE Class 12 Biology past-paper question from the 2024board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.