I. No virus can survive in ocean waters. 

II. No virus can infect bacteria. 

III. No virus can change the cellular transcriptional activity in host cells. 

How many of the statements given above are correct? 

(a) Only one 

(b) Only two 

(c) All the three 

(d) None

Ans-d

Explanation

Viruses inhabit the world’s oceans in great numbers. One spoonful of seawater can hold up to a billion virus particles

Hence statement 1 is incorrect 

A bacteriophage is a type of virus that infects bacteria. The word “bacteriophage” literally means “bacteria eater,” because bacteriophages destroy their host cells. 

Hence statement 2 is incorrect 

The ability to shut off host gene expression is a shared feature of many viral infections, and it is thought to promote viral replication by freeing host cell machinery and blocking immune responses. 

Hence statement 3 is incorrect

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