Question:

Statement I : The codon 'AUG' codes for methionine and phenylalanine. Statement II : 'AAA' and 'AAG' both codons code for the amino acid lysine. In the light of the above statements, choose the correct answer from the options given below.

Updated On: Nov 13, 2025
  • Both Statement I and Statement II are true
  • Both Statement I and Statement II are false
  • Statement I is correct but Statement II is false
  • Statement I is incorrect but Statement II is true
Hide Solution
collegedunia
Verified By Collegedunia

The Correct Option is D

Solution and Explanation

In this question, we need to evaluate two statements based on the genetic coding of amino acids:

  1. Statement I: "The codon 'AUG' codes for methionine and phenylalanine."
    • Explanation: In the genetic code, 'AUG' serves a dual role. It codes for the amino acid methionine and also acts as the start codon, initiating protein synthesis. However, it does not code for phenylalanine.
    • Conclusion: Therefore, Statement I is incorrect because 'AUG' does not code for phenylalanine.
  2. Statement II: "'AAA' and 'AAG' both codons code for the amino acid lysine."
    • Explanation: In the genetic code, both 'AAA' and 'AAG' codons specifically code for the amino acid lysine.
    • Conclusion: Thus, Statement II is correct.

Given this analysis, the correct answer is: Statement I is incorrect but Statement II is true.

Was this answer helpful?
0
0

Concepts Used:

Biomolecules

Biomolecules are the most essential organic molecules, which are involved in the maintenance and metabolic processes of living organisms. These non-living molecules are the actual foot-soldiers of the battle of sustenance of life.

There are four major classes of Biomolecules –  Carbohydrates, Proteins, Nucleic acids and Lipids.

  1. Carbohydrates are chemically defined as polyhydroxy aldehydes or ketones or compounds which produce them on hydrolysis.
  2. Proteins are another class of indispensable biomolecules, which make up around 50per cent of the cellular dry weight. Proteins are polymers of amino acids arranged in the form of polypeptide chains. The structure of proteins is classified as primary, secondary, tertiary and quaternary in some cases.
  3. Nucleic acids refer to the genetic material found in the cell that carries all the hereditary information from parents to progeny. There are two types of nucleic acids namely, deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). The main function of nucleic acid is the transfer of genetic information and synthesis of proteins by processes known as translation and transcription.
  4. Lipids are organic substances that are insoluble in water, soluble in organic solvents, are related to fatty acids and are utilized by the living cell.