Question

Assertion :Comparative biochemistry provides a strong evidence in favor of a common ancestry of living beings. Reason: Genetic code is universal.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.
• C. Assertion is correct but Reason is incorrect.
• D. Both Assertion and Reason are incorrect.

Answer 1

The correct option is A Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.

All organisms follow same path of biochemical path for flow of genetic information which strongly support their phylogenetic relationship. Replication of DNA copies the genetic information present in it which is transcribed into RNA by RNA polymerase enzyme. The RNA sequence of ribonucleotides is translated into amino acid sequence of polypeptides by process of translation. Thus, flow of genetic information is unidirectional and follows the path: DNA --> RNA --> protein. Assertion is correct. Biochemical homology between organisms has its foundation in genetic code, a set of triplets codes for an amino acid, which specify codons for each of 20 standard amino acids. Genetic code is universal which means that a gene segment from fruit fly codes for same sequence of amino acids as in human cells which support the common ancestry among them. Reason is correct and provides correct explanation for assertion.