What is the most common threat to a host organism posed by an invading virus

The question is incomplete, the complete question is:

What is the most common threat to a host organism posed by an invading virus.

A)Production of viral fluids in the bloodstream

B)Fermentation of acids in the digestive system

C)Destruction of cells by viral reproduction

D)Stimulation of muscle tone in the heart

The correct answer is C

Explanation:

A virus is a microscopic organism that is incapable of replicating on its own, hence it must infect its host cell using its host cell processes to replicate. The viral replication cycle can cause severe biochemical and structural change in the host cell, resulting to cell damage.

Viruses are very host specific, hence, their infection is dependent on the type of host. However, most productive viral infections (that will lead to virions) follow similar steps in the viral replication cycle.

The virus initially attaches to specific receptor site on its host cell membrane, the virus then makes entrance into the host cell and incorporates its genetic material into that of the host. This incorporation, induces the host cell to replicate and transcribe the viral genome using its replication and gene expression abilities. After the replication, the newly produced virions (a single individual viral particle) in the host organisms needs to be released. The virions are either released when the host cell becomes lysed (as in bacteriophage infection of a bacterium cell) or leave the infected cells by budding through the membrane without directly killing the host cell (as in HIV infection of human cells).

blood enters the heart through two large veins, the inferior and superior vena cava, emptying oxygen-poor blood from the body into the right atrium of the heart. as the ventricle contracts, blood leaves the heart through the pulmonic valve, into the pulmonary artery and to the lungs where it is oxygenated.