Question

The smallest segment of a gene which can undergo mutation is called
A. Muton
B. Recon
C. Cistron
D. Interferon

Answer 1

Hint: A permanent alteration in the DNA sequence in the cell’s genome that makes up a gene is known as gene mutations. Mutation takes place during DNA replication. If the DNA is damaged for any reason, the mutation occurs. When a mutation takes place, the components of a gene become altered, or it may interfere with the activity of the gene.

Complete answer:
The basic physical and functional unit of heredity, which is transferred from a parent to offspring, from a generation to next, and determine some of the characteristics of the offspring is known as a gene. Generally, a gene is a sequence of nucleotides in DNA or RNA. When the nucleotide sequence of the genome of an organism permanently changes is known as mutation. Mutations occur during DNA replications due to low frequency owing to the chemical instability or the errors during DNA replication.
It is found that the gene is not the unit of either function or recombination or mutation. So, it is necessary to divide the gene into further divisions to define the units of function, recombination, and mutation. The gene is further divided into divisions called cistron, recon, and muton.
A gene consists of many cistrons. Cistron, a segment of DNA, is the largest element of a gene. There are hundreds of mutons, and recons found in each cistron. During protein synthesis, cistron encodes the polypeptide. Both the structural and regulatory sequence includes cistron. The word cistron refers to a test called the cis-trans test. This cis-trans test is similar to a complementation test. Cistron is the unit of function.
Recon is the unit within a gene that is capable of recombining genetically. It is a unit of recombination. Recon structurally consists of one or two pairs of nucleotides. The recombination cannot occur within recon. There occurs a minimum distance between the adjacent recons within a gene.
Interferons are made up of proteins and it is released by host cells. Interferons respond to the conditions arising due to the presence of pathogens such as viruses, bacteria, parasites, or tumour cells. Interferons are capable of interfering with viral replication within host cells.
A part of the gene that is capable of undergoing mutation has been called the muton. It is the shortest unit within a gene that can undergo mutation. The muton is composed of one or many pairs of nucleotides. Muton is the element that leads to the production of a mutant phenotype. Each recon contains several mutons within them, and many mutons stay linked due to recombination within a recon.

Therefore, the correct option is option A.

Note:
The gene transfers genetic information from one generation to the next. Gene is responsible for the physical, physiological, or biochemical characteristics of the organisms. But this gene can be muted due to chemical instability or the errors during DNA replication. A gene is further divided into smaller units such as cistron, recon, and muton as a unit of function, recombination, and mutation. Thus, the muton is the shortest unit that can be involved in mutation.