SBA — Single Best Answer · Review
Question 570
Genetics → General
Classification
Question
SSBAOptions
Explanation
An exon is a DNA segment containing information coding for protein or peptide sequences. Production of a complementary RNA copy from DNA is transcription. The subsequent reading of mRNA by ribosomes to direct polypeptide synthesis is translation. The question therefore describes an exon and translation, respectively.
Option Validity
A) The DNA segment is an exon, but transcription produces RNA from DNA; the ribosomal step described is translation.
C) Translation correctly identifies the ribosomal step, but an intron is an intervening gene sequence rather than the protein-coding segment described.
D) Neither term fits: the described coding segment is an exon, and the ribosome performs translation rather than transcription.
E) Translation is correct, but a promoter is the DNA region where RNA polymerase binds to initiate transcription, not the protein-coding segment described.
Further Reading
Saxena R. Textbook for MRCOG-1: Basic Sciences in Obstetrics and Gynaecology. 1st ed. Jaypee Brothers Medical Publishers; 2016. Chapter 8: Genetics — Process of Protein Synthesis; Gene. Printed page 255.