Observation the action or process of observing something or someone carefully or in order to gain information:
In low light no plants grow. With no plants no animals can eat so less animals remain or stay there. With less animals less animals respire and breathe out CO2.
The role of DNA in all cells is to produce molecules of RNA that are involved in protein synthesis. Through the proteins, all the metabolism of the cell is controlled. DNA is also used to synthesize new DNA for daughter cells.
They begin to form about 3.8 billion years ago