Physiology focuses on the systems and organs of human musculoskeletal system pdf human body and their functions. Elements of the human body by mass.
These elements reside in trillions of cells and non-cellular components of the body. This is made up of about 19 litres of extracellular fluid including about 3. 2 litres of blood plasma and about 8. 23 litres of fluid inside cells. The content, acidity and composition of the water inside and outside cells is carefully maintained.
Not all parts of the body are made from cells. Of the 70 kg weight of an average human body, nearly 25 kg is non-human cells or non-cellular material such as bone and connective tissue. Proteins dictate cell function and gene expression, a cell is able to self-regulate by the amount of proteins produced. Endothelial cells are cells that line internal cavities including blood vessels and glands.