Question
Which of the following statements are correct with reference to packaging of DNA helix ?
A. Histones are organized to form a unit of eight molecules called histone octamer.
B. Histones are negatively charged basic proteins.
C. Histones are rich in the basic amino acid residues - lysine and arginine.
D. The positively charged DNA is wrapped around the histone octamer to form nucleosome.
E. The packaging of chromatin at higher levels requires an additional set of proteins called non-histone chromosomal proteins.
Choose the correct answer from the options given below :
This question was previously asked in
NEET UG Re-Exam 2026 Question Paper (21-Jun-2026)
The correct answer is
A, C and E only
DNA Packaging: Analyzing Statement Accuracy
This question assesses understanding of DNA packaging within eukaryotic cells, focusing on the role of histone proteins and chromatin structure.
Statement Analysis
- A. Histones form histone octamers: This statement is correct. Histones assemble into a core structure containing eight protein molecules (two each of H2A, H2B, H3, and H4), known as the histone octamer.
- B. Histones are negatively charged basic proteins: This statement is incorrect. Histones are positively charged basic proteins.
- C. Histones rich in lysine and arginine: This statement is correct. Histones contain a high proportion of basic amino acids, specifically lysine and arginine, which are positively charged.
- D. Positively charged DNA wraps around histone octamer: This statement is incorrect. DNA carries a negative charge due to its phosphate backbone. The positively charged histone octamer interacts with and wraps the DNA.
- E. Non-histone proteins in higher-level packaging: This statement is correct. Further condensation and organization of the chromatin fiber involve additional proteins known as non-histone chromosomal proteins.
Conclusion on Correct Statements
Based on the analysis, statements A, C, and E are correct regarding DNA helix packaging.
Identifying the Correct Option
The option that includes only the correct statements (A, C, and E) is Option 3.
Was this answer helpful?
Similar Questions
- Arrange the following steps of DNA fingerprinting in a correct sequence.
A. Isolation of DNA and its digestion by restriction endonucleases.
B. Hybridisation using a labelled VNTR probe.
C. Transferring of separated DNA fragments to synthetic membranes.
D. Detection of hybridised DNA fragments by autoradiography.
E. Separation of DNA fragments by electrophoresis.
Choose the correct answer from the options given below : - In the lac operon, the z gene codes for :
- The correct statement with regard to the secondary structure of DNA/RNA is :
- Which of the following statements are correct with reference to a transcription unit ?
A. A transcription unit in DNA is defined primarily by three regions : promoter, structural gene and terminator.
B. The promoter is said to be located towards the 5'-end of the structural gene.
C. The promoter is a DNA sequence that provides binding site for RNA polymerase.
D. The promoter defines the template and coding strands.
E. The terminator is located towards the 3'-end of the coding strand and it defines the end of the process of transcription.
Choose the correct answer from the options given below : - Which of the following statements about lac-operon is correct ?
- Which of the following enzymes synthesizes precursor mRNA ?
Important Questions from Molecular Biology
- Arrange the following steps of DNA fingerprinting in a correct sequence.
A. Isolation of DNA and its digestion by restriction endonucleases.
B. Hybridisation using a labelled VNTR probe.
C. Transferring of separated DNA fragments to synthetic membranes.
D. Detection of hybridised DNA fragments by autoradiography.
E. Separation of DNA fragments by electrophoresis.
Choose the correct answer from the options given below : - In the lac operon, the z gene codes for :
- The correct statement with regard to the secondary structure of DNA/RNA is :
- Which of the following statements are correct with reference to a transcription unit ?
A. A transcription unit in DNA is defined primarily by three regions : promoter, structural gene and terminator.
B. The promoter is said to be located towards the 5'-end of the structural gene.
C. The promoter is a DNA sequence that provides binding site for RNA polymerase.
D. The promoter defines the template and coding strands.
E. The terminator is located towards the 3'-end of the coding strand and it defines the end of the process of transcription.
Choose the correct answer from the options given below : - Which of the following statements about lac-operon is correct ?
Need Expert Advice?
More Questions from NEET
