Virus
Table of Contents
Virus is actually the genetic material inside the protective cover, the capsid. The whole package of genetic material and the capsid, is called virion.
1. Importance in evolution
Virus may predate DNA based lifeform. And they maybe one of the earliest beings to come in existence. Quiet a lot of genetic material in our cells was brought by infection from virus. And as such virus help / are an instrument in tramitting genetic material.
2. Mutation
Due to the huge number of viruses an infected cell produces and due to the huge number of viruses present, the replication of virus is very high in frequency. Hence, virus undergo mutation and develop strain quickly. Each day a new strain of a virus may be produced. (e.g. that's why we need flu shots each new flu season).
3. Interplanetary travel
There are two ways virus can spread from one planet to other.
3.1. Panspermia spellling
Virus in small droplets of water can reach very high altitude in the atmosphere. From there they may even reach the outer space through radiation pressure. This way a lot of virus are spread from the Earth. However in the space, due to high radiation, and the droplets may dry up, the capsid may break and viruses die. Thus most of the viruses are destroyed by solar radiation.
3.2. Lithogneospermia spellling
When an asteroid strikes a planet, fragments of the lithospehere i.e rocks flew out in the space. These rocks can carry virus inside them. Although quantity of virus spread by this method is small, those viruses are protected from radiation.
