Section 1 interferon question

[datfatcat]

Interferon is a recently-discovered anti-viral protein which, it is hoped, will provide general protection against virus infection; it is manufactured by a virus-infected organism within hours of a virus attack. Virus particles consist of genetic material and protein; they are able to reproduce inside the cells of another organism (the host).
 A virus comes in contact with the cell (1), penetrates the cell membrane, and thus infects the cell. The virus then releases its own genetic material (2) which 'organises' the infected cell to commence the manufacture of copies of the viral genetic material (3). This new genetic material (4) can use materials from the host cell to make its own protein and form new virus particles, and these new virus particles are released into the fluid around the cells (5) where they can now spread to other cells.

During the early stages of infection, the process of viral multiplication within the cell stimulates (2A) the nucleus of the cell to manufacture interferon. Through a series of complex processes, the interferon protein is made (2B) and released rapidly (2C) into the fluid surrounding the cell.

Under certain conditions, interferon may be manufactured by an alternative process using precursor material (2B') already present in the cell.

The interferon from an infected cell stimulates the surrounding cells (2D) to produce anti-viral protein (2E) which acts to change the cell's protein-making machinery (2F) so that it cannot be used by the genetic material in the virus particles with which it comes into contact. Therefore, although infection by a new virus of an unaffected cell (6) still leads to the release of viral genetic material inside the cell (7), the viral genetic material is discriminated against by the cell machinery responsible for making new proteins so that no additional virus particles are produced. As virus multiplication is thus prevented, the cell is protected. The degree of protection of any cell is dependent on the amount of anti-viral protein present.

The action of interferon on a cell makes it difficult for

Select one:
A. viruses to enter that cell.
B. viruses to reproduce in that cell.
C. the cell to multiply.
D. the cell to carry out its functions as part of an organ or tissue.

(Tell me why it is B, not C)

[shinny]

Because cell multiplication has nothing to do with the action of interferon. Interferon stops the protein factories of cells from working, therefore preventing multiplication of the VIRAL particles. It has no effect on the HUMAN CELL's ability to replicate - which is what C is referring to.