That is because gene expression is a process in the synthesis of proteins and without proteins our organisms could not function properly. Almost all things that occur in our body are results of proteins being synthesized and these proteins travel through our body activating other processes. When not synthesizing proteins, different types of RNA are synthesized.
The natural flow of rivers can be affected by several factors, such as building dams to provide drinking water, pumping of groundwater, climate change, and building of lands that change how natural water runs into surfaces and into rivers. All of these also disrupt the balance of ecosystem in the area.
