No, because everyone has different DNA and genetics.
When your body gets overheated. This is a negative feedback loop. The arteries/veins will dilate letting more blood pass through. Your face tends to get red because there is more blood flow towards the surface in an effort to cool off. This is also why you sweat.
Exchange of nutrients occurs in the digestive system. Exchange of oxygen occurs in lungs
They're called Enzyme. They're made up of proteins. They act as a biological catalysts that can speed up chemical reaction. They have an active site that certain substrates binds into it and form a product. Enzyme works under optimum pH and temperature and the active sites are not changed unless denatured.