Since viruses have RNA or DNA, aren't they alive?


No. The presence of DNA is only 1 of 4 conditions for life, as spelled
out in Module 1. Please note that the presence of RNA is NOT a condition
for life, so the viruses that use RNA do not even meet that criterion.

Remember the other 3 conditions:

2. Ability to sense and respond to the surroundings

3. Ability to take in energy from the surroundings and convert it into
energy to sustain itself (In other words, life needs food)

4. Ability to reproduce

Viruses have #2, but they do not have #3. They do not produce their own
food or eat other food. They also really don't have #4. The only way
they can reproduce is by invading a living cell and hijacking its
reproductive machinery.

Thus, since viruses do not have two of the four characteristics of life,
we do not consider them to be living. They are just highly-structured and
complex chemicals. Remember, arsenic can invade and kill a cell, and it
is not alive, either! It is just a chemical. Viruses are just very
complicated chemicals.

Tags: Biology
Last update:
2019-02-05 21:40
Author:
Sue
Revision:
1.1
Average rating:0 (0 Votes)

You cannot comment on this entry

Chuck Norris has counted to infinity. Twice.

Records in this category

Tags