Question

Which of the following is the smallest virus?
A. Foot and mouth virus
B. Tobacco mosaic virus
C. Coliphage lambda virus
D. Wound tumor virus

Answer 1

Hint: This is a type of air borne virus. It is very highly communicable and can transmit upto many kilometers. A virus is an infectious submicroscopic agent which replicates only within an organism's living cells.

Complete Answer:
- Viruses infect all forms of life, including the bacteria and archaea, from animals and plants to microorganisms. In many cases, viruses propagate. Viruses are typically transmitted from plant to plant by insects fed on plant seed. One transmission route is through disease - bearing species known as vectors.
- The Foot-and - Mouth (FMDV) virus is the pathogen responsible for the disease of foot-and-mouth. It is a picornavirus, the Aphthovirus genus's prototypical member. This virus is almost 0.008 to 0.012 micron in size. The disease that triggers the vesicles in the mouth and feeds of bovids, suids, and cloven-hoofed animals is extremely infectious.
- The virus (25-30 nm) has an icosahedral protein capsid without an envelope which contains a stranded ribonucleic acid genome with a positive sensory material.
- Tobacco mosaic virus (TMV) is a single-stranded RNA virus, in the Tobamovirus genus that infects a large variety of plants, in particular, tobacco and the Solanaceae family. Characteristic patterns such as "mosaic" mottling and discoloration in the leaves are caused by infection. The first discovered virus was TMV.
- TMV particles are 300 nm hollow cylinder longitudes of 18 and 4 nm external and internal diameters.
- Bacterial or bacteriophage virus Coliphage lambda virus is a bacterial virus that is infective to Escherichia coli, causing DNA to be expelled into a bacterial cell cytoplasm in the head of the phage via the tail.
- Wound tumour virus is an invertebrate and plant disease of the Phytoreovirus and Reoviridae families, which are found in the United States of America. The virus is a Baltimore classification system type III virus with a dual-stranded RNA genome.

Thus, the correct answer is option A. i.e., Foot and mouth virus.

Note: Viruses show a large diversity of sizes and shapes. Normally, viruses are smaller than bacteria. Most viruses have a diameter between 20 to 300 nanometers. The smallest animal viruses belong to the picornaviridae and parvoviridae families.