The process by which oxygenreleased into the atmosphere by photosynthetic organisms is taken up by aerobic organisms while the carbon dioxide released as a by-product of repiration is taken up for photosynthesis. Origin ofoxygen cycle Expand.
Answer:
By the process of cellular differentiation which consists of physical and functional changes of the cell used by processes at the genetic level. The expression of these in each type of cell is different. That is to say that the type of cell follows at a time of development there is differential activation of some genes and repression of others
Replication/ reproduction. one side copies then replicates and matches up. hope this helps
Answer:
Answer b is the right one