Select false statement :

Question

Accepted Answer

The correct option is 1:
The question asks to select the *false* statement, which means option 1 is the correct answer because the statement it presents is factually incorrect. Genes are not proteins; rather, they are functional segments of the long deoxyribonucleic acid (DNA) molecule found within a cell's nucleus or cytoplasm. A gene contains the specific sequence of nucleotide bases (A, T, C, G) that acts as the blueprint or code for creating a particular protein or a functional RNA molecule. Proteins, on the other hand, are the molecules constructed from chains of amino acids (polypeptides) based on the instructions copied from the gene. Therefore, a gene is the instruction set (DNA) and a protein is the functional product built from that set.

The incorrect option is 2:
The statement "The functional unit of DNA can be regarded as cistron" is a true statement, and therefore not the false statement the question seeks. The term **cistron** was introduced by the geneticist Seymour Benzer to provide a precise molecular definition for the functional unit of a gene. Specifically, a cistron is defined as the segment of DNA (or RNA) that codes for a single polypeptide chain in protein synthesis. In the context of modern genetics, the term 'gene' and 'cistron' are often used interchangeably, particularly for the functional unit responsible for a protein product.

The incorrect option is 3:
The statement "Recon is the smallest unit of DNA capable of recombination" is a true statement and is scientifically accurate. **Recon** is another term coined by Seymour Benzer to describe the unit of recombination. It represents the smallest element of genetic material that can be separated from its adjacent material by a crossover event. The experimental data showed that the recon is incredibly small, corresponding to the distance between two consecutive nucleotide pairs.

The incorrect option is 4:
The statement "Operon model was first suggested by Jacob and Monod" is a true historical fact in molecular biology, making it an incorrect choice for the false statement. The **Operon Model** was a groundbreaking concept proposed by the French biologists François Jacob and Jacques Monod in 1961. This model explained the mechanism for the regulation of gene expression in bacteria, particularly through their work on the *lac* operon. This model introduced the key concepts of the promoter, operator, and regulator genes working in a coordinated unit to control the synthesis of structural proteins.