Question

Cryptogram of TMV is:
A. $\dfrac{R}{2}$:$\dfrac{2}{5}$:$\dfrac{E}{E}$:$\dfrac{X}{S}$
B. $\dfrac{R}{1}$:$\dfrac{2}{5}$:$\dfrac{E}{E}$:$\dfrac{S}{X}$
C. $\dfrac{R}{1}$:$\dfrac{1}{8}$:$\dfrac{S}{S}$:$\dfrac{S}{{AP}}$
D. $\dfrac{R}{1}$:$\dfrac{2}{7}$:$\dfrac{E}{E}$:$\dfrac{S}{A}$

Answer 1

Hint: Cryptogram of virus is the descriptive code summarizing the main properties of a virus. The viruses have been named by a system of nomenclature as designated by the International Committee of Virus Nomenclature.

Complete Answer:
- TMV stands for Tobacco mosaic virus is a positive-sense single-stranded RNA virus species in the genus Tobamovirus that infects a wide range of plants, especially tobacco and other members of the family Solanaceae.
- It is the first pathogen identified as a virus. Two scientists contributed to the discovery of the first virus, tobacco mosaic virus. Ivanoski reported in 1892 that extracts from infected leaves were still infectious after filtration through a Chamberland filter-candle.
- TMV is the type member of a large group of viruses within the genus Tobamovirus. The rod-shaped virus-particles of TMV measure about $300nm \times 15nm$. A single TMV particle is composed of 2,130 copies of the coat protein that envelope the RNA molecule of about 6,400 nucleotides.
- The viruses have been named by a system of nomenclature as designated by the International committee of virus Nomenclature. It consists of two parts:
1. The first part is the common name of the virus.
2. The second part consists of a coded information of it.

Hence, the correct answer is option (B).

Note: TMV or tobacco mosaic virus is a widespread plant pathogen, is found in tobacco (including cigarettes and smokeless tobacco) as well as in many other plants. Plant viruses do not replicate or cause infection in humans or other mammals.