We have heard about Respiration. In human beings, respiration is a cellular activity which takes place in the presence of oxygen and in result produces carbon dioxide. Jamal model is a clear manifestation of that process. Medulla is the region of a brain that controls the respiration activity. When we breathe we take in oxygen and the excess amount of carbon dioxide is removed from out body.
Brains cells have capability to detect the carbon concentration in blood and add excess amount of carbon from body to the air.
In a cell, there are several parts of it that are there to stop this from happening. Cancerous cells do not have the genetic code to stop growing and reproducing. A regular cell will actually destroy itself it there is a mutation. If it does not get destroyed, it could potentially be tumorous, then it could eventually be cancerous.
All of these are necessary, but what you need the most I would say is
D. Movement
Without movement, your body can stiff up, causing muscle problems which can lead to many various things.