Answer
Cellular theories of aging
The theoretical perspective that cross-linking represent is the cellular theorie of aging.
Explanation;
Cellular theories of aging are theories of aging that focuses on processes that occur within individual cells. One theory is the buildup of harmful substances in cells over one's lifetime. Another is a limit on the number of times cells can divide, possibly caused by the shortening of the telomeres.
It is hard to understand this question but ill give you my best answer. The hearts level of organisation to cells is immense, the heart pumps blood to every cell in the body (so they can respire) through a system of Arteries, veins and capillaries. The blood is pushed by the force of the heart through the arteries, the main (and largest) tubes for transportation to segments of the body further away from the heart. This goes into a smaller system of veins that brake off into a tree kind of pattern to reach every cell. These later brake off into the capillaries that have walls only 1 cell thick. This is how blood is transported to each cell that requires energy and oxygen to respire.
Water has a high latent heat of vaporisation meaning it takes a lot of energy to make water evaporate. This is because it takes a lot of energy to overcome the hydrogen bonds and intermolecular forces in a water molecule.
