Class 12 · Molecular Basis of Inheritance

Codon Reading: Contiguous & No Punctuation — NEET Biology

✅ Asked in NEET 2024
✅ NEET 2024 PYQ

Which of the following is not a characteristic feature of the genetic code?

QuestionNEET 2024

Which of the following is not a characteristic feature of the genetic code?

Answer & NCERT explanation

Correct answer: C The code has punctuations

The genetic code does NOT have punctuations - it is comma-less and continuous. This means there are no gaps or punctuation marks between codons; they are read continuously in triplets. The other features are correct: codons are triplets (3 bases), the code is nearly universal across species, and it is degenerate (multiple codons can code for the same amino acid). The absence of punctuation is a key characteristic that allows continuous reading of the genetic message.

Read more NCERT concept on the PYQ

📖 NCERT Source

The codon is read in mRNA in a contiguous fashion. There are no punctuations.

NCERT Biology · Class 12 · Chapter 5 · Paragraph 95
How NTA Uses This Concept

The genetic code is read continuously on mRNA without any gaps, spaces, or punctuation marks between codons. This means ribosomes read codons sequentially (AUG-UUC-GUA...) without pausing between them. Students often mistakenly think there are separators or overlapping regions between codons, leading to incorrect interpretation of protein synthesis. NTA tests this by asking how codons are identified or what happens if the reading frame shifts. Remember: codons are adjacent three-nucleotide units with no interruptions—this is why a single nucleotide insertion or deletion causes a frameshift mutation affecting the entire downstream sequence.

❓ Frequently Asked Questions
What does NCERT say about codon read mRNA contiguous?
The codon is read in mRNA in a contiguous fashion. There are no punctuations.
Has this concept appeared in NEET?
Yes — appeared in NEET 2024. Explicitly states 'codon is read contiguous, no punctuations'
Which chapter is this from?
Molecular Basis of Inheritance, Class 12 NCERT Biology.

Through deep analysis of NEET and NTA, 88 of 90 questions from the NEET 2026 paper were matched straight from the MedicNEET Biology question bank.

88/90
of the NEET 2026 Biology paper matched from the MedicNEET question bank

MedicNEET's Biology question bank is built from the same NCERT lines NTA picks repeatedly. Not random MCQs — questions crafted exactly like NTA crafts them.

88 of 90 NEET 2026 Biology questions traced to MedicNEET14,000+ Biology questionsHindi + English
Free to start · Hindi + English · 22,000+ questions · NEET 2026 pattern
Related Concepts from Molecular Basis of Inheritance
📘Practice all 84 NEET PYQs from Molecular Basis of Inheritance