Seeing that our species is constantly evolving, maybe it is starting to get more uncomfortable to walk on all fours.
Four chambered heart keeps oxygenated and deoxygenated blood separate and has double circulation while three chambered heart has a single circulation. Two chambered heart only has single atrium and single ventricle
When the cell gains glucose, the process of glycolysis occurs and then the glucose is broken down into pyruvate.
Now, in pyruvate processing, Acetyl CoA is produced and used in the Krebs Cycle.
During that process, NADH and FADH2 are made and go into the electron transport chain. That is where water and ATP are made.
The cartilage of septum!!!
In order for natural selection to take place we must have "variety in a population". This variety of traits is what allows natural selection to "pick" the most favorable traits.
