Because mostly some microorganism may be very small and harmful that can affect humans or animals just by the experience of the microorganism.
Analogies are the result of convergent evolution. Interestingly, though bird and bat wings are analogous as wings, as forelimbs they are homologous. Birds and bats did not inherit wings from a common ancestor with wings, but they did inherit forelimbs from a common ancestor with forelimbs.
Their valency is one and both belong to the third period
Answer:
This question is not well placed. It should be " a relationship between two organisms in which both benefit is called".
The answer is SYMBIOSIS
Explanation:
Living organisms tend to interact with one another in their natural environment. This interaction are of different types depending on the effect on the involved organisms. One of those interactions is SYMBIOSIS. Symbiosis is a relationship between two organisms in which both of the organisms benefit from one another.
An example is the relationship between the "CATTLE AND EGRET". The cattle provides food for the egret when they feed on the insect parasites on their body while the egret helps the cow get rid of detrimental parasites.
