The reason people who have AIDS can't fight it off is because it is an immune disease it quickly weakens the immune system and makes a persons body too weak to fight anything off.
DNA helps to build the genetic structure of organisms. DNA tells the cells of the organism how to act and what to do.
I hope that helped.
The most powerful approach to isolating a single mutant from a population of billions is positive selection.
The answer is gonna be A ecosystem
Answer:
Certain species need different environments to live in and if its too cold for one species it can lead to death of the population of that species.
that is what I put
Explanation:
