Why virus is not considered as a cell?

Question

A virus has a genetic material like those found in nucleus of the cell, however, it is not considered as a cell. Why?

Answer 1

A virus is a microorganism that reproduces inside the cells of living hosts. When infected by a virus, a cell is forced to make thousands of identical viruses. They reproduce at an extraordinary rate, but the viruses cannot do this alone: their reproduction is entirely dependent on their presence within a host cell. Unlike most living things, viruses do not have cells that divide; new viruses are assembled in the infected host cell.

A virus consists of two or three parts: all viruses have genes made from either DNA or RNA, long molecules that carry the genetic information; all have a protein coat that protects these genes; and some have an envelope of fat that surrounds them when they are not within a cell. Viruses vary in shape from the simple helical and icosahedral to more complex structures. Viruses are about 100 times smaller than bacteria, and it would take 30,000 to 750,000 of them, side by side, to stretch to 1 centimetre (0.39 in).

Viruses spread in many different ways. Plant viruses are often spread from plant to plant by insects and other organisms, known as vectors. Some viruses are spread by blood-sucking insects. Each species of virus relies on a different method. Whereas viruses such as influenza are spread through the air by people's coughing and sneezing, others such as norovirus, which are transmitted by the faecal-oral route, contaminate hands, food and water. Rotavirus is often spread by direct contact with infected children. HIV is one of several major viruses that are transmitted during s*x. The origins of viruses is unclear: some may have evolved from plasmids—pieces of DNA that can move between cells—while others may have evolved from bacteria.

Viral infections often cause disease in humans and animals; they are usually completely eliminated by the immune system, and this confers lifetime immunity to the host for that virus. Antibiotics have no effect on viruses, but antiviral drugs have been developed to treat life-threatening infections. Vaccines that produce lifelong immunity can prevent some viral infections.

Answer 2

Since viruses are only strands of DNA/RNA with a protein coat(capsid). Therefore they are not considered as cell. However, when they come in contact with their respective host cell, they start living using host's cell for their cellular activities.

Answer 3

because it is not alive....it can only considered alive if it already infiltrated its hosts' body and will engulf the cells,,  

Answer 4

living organisms(which are made of cells) can:

-move

-feed

-respire

-excrete

-reproduce

-respond

the olny thing viruses can do is to reproduce so they are not considered as living orgaisms or cells. there r rather considered as chemicals

Answer 5

it depends on other organisms to duplicate. in its structure, it doesnt have a nucleus, but rather a mass of protein codes. and cover.  

Answer 6

Some consider them non-living as they do not meet all the criteria , however, viruses have genes and evolve by natural selection.