Question

TMV has been isolated from virtually all commercial tobacco products. Why, then, is TMV infection not an additional hazard for smokers?

Short answer

Tobacco mosaic virus is a plant virus that infects tobacco and other plants by replicating its particles through plasmodesmata. Plant viruses cannot replicate in humans and other mammals because they cannot bind to the receptors on the membranes of cells of humans and mammals.

Step-by-step solution

Step 1: TMV (Tobacco Mosaic Virus)

TMV is a single-stranded RNA virus that can cause a wide range of plants infections. The primary symptoms are discoloration of leaves, mottling, and drying of leaves. It was the first virus that was discovered and crystallized in the lab by W.M. Stanley.

Step 2: Tobacco

Tobacco is a plant grown for its leaves. The leaves are processed to produce tobacco products. It contains nicotine that leads to addiction. It is challenging for addicts to quit it. Also, many harmful chemicals are released while burning tobacco leaves.

Step 3: Effects of TMV on humans

TMV has no effects on human beings because they are not in the range of the host of TMV. TMV can only affect plants, not humans or mammals because they lack the receptors on their cells for TMV.

So, they cannot be infected by TMV. Also, smokers have a large count of anti-TMV antibodies, so they do not experience harmful effects by infection of this virus that only affects the range of plants as a host.