Physiology focuses on the systems and organs of the human body and their functions. Elements of the human body by human anatomy pdf free download. 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. Lining cells regulate what can and can’t pass through them, protect internal structures, and function as sensory surfaces. The endocrine hormones serve as signals from one body system to another regarding an enormous array of conditions, and resulting in variety of changes of function.
The skin provides containment, structure, and protection for other organs, and serves as a major sensory interface with the outside world. The lymphatic system is similar to the circulatory system in terms of both its structure and its most basic function, to carry a body fluid. It gives the body basic structure and the ability for movement. 9 months of development of the infant. The body consists of a number of different cavities, separated areas which house different organ systems.