Answer:
Because they don't have fertilizer.
Explanation:
Well, if this was a long time ago, then farmers did not have fertilizer. So, there are bacteria on the roots of plants that convert nitrogen into a usable form. It's very important for growing, and when farmers harvest the crop, not much of the nitrogen is returned to the land, so it is not as fertile. Fertilizer is largely consisted of nitrogen, so that is why farmers use fertilizers today. But "a long time ago," farmers did not have fertilizer.
Answer:
The main function of the DNA polymerase is to synthesize DNA by the process of replication.
Explanation:
It is an important process to maintain and transfer genetic information from one generation to another. DNA polymerase works in pairs, replicating two strands of DNA in tandem.
Lack of antibodies because thats the stuff to fight things away