- A Coding directly for a protein enzyme that catalyzes the replication of DNA
- B Coating the inactive X chromosome and recruiting silencing factors (X-inactivation)
- C Repairing double-strand breaks within damaged genomic DNA exclusively, with no other role
- D Directing and catalyzing the translation of mRNA transcripts at the ribosome
Correct answer: B. Coating the inactive X chromosome and recruiting silencing factors (X-inactivation)
Explanation: XIST (X-inactive specific transcript): long non-coding RNA transcribed from the X inactivation center. Coats the X chromosome in cis, recruiting polycomb and other silencing factors.
Concept context
Mendel's laws, inheritance patterns, DNA structure, and molecular biology. Core of NEET biology.
Read the full Principles of Inheritance and Variation notes →