Human physiology: from cells to systems - All Explained

The body is composed of many trillions of cells. Each cell is a self-contained, living entity. With the exception of red blood cells, cells of the same type join together, using inter­-cellular substances to form tissues, such as muscle tissue. One, two, or more tissues combine in a particular way to form more complex structures, called organs. All organs contribute to nutritional health, and a person's overall nutritional state deter­mines how well each organ functions. At a still higher level of coordination, several organs can cooperate for a common purpose to form an organ system, such as the digestive system. Overall, the human body is an organism made up of a coordinated unit of many highly structured organ systems.

Chemical processes (reactions) occur constantly in every living cell: The production of new substances is balanced by the breaking down of older ones, as exemplified by the constant formation and degradation of bone. For this turnover of substances to occur, cells require a continuous supply of energy in the form of dietary carbohydrate, protein, and/or fat. Cells also need water and building supplies for the turnover to occur. Amino acids, minerals, chemical regulators, and vitamins are some examples of genetic material that need the materials to break down. All of these substances enable the tissues, constituted from individual cells, to function properly.

Getting an adequate supply of all nutrients to the body's cells begins with a health­ful diet. You must have a daily intake of grain, fruits, vegetables, meats, and dairy to keep your organs functioning properly. All of these food groups provide an important vitamin or nutritional benefit for your body. To see how much of each food group your body requires, make sure to check out the latest food pyramid. To assure optimal use of nutrients, the body's tissues, organs, and organ systems also must work efficiently.

This article covers subject material concerned with the anatomy and physiology of the cell and major organ systems, especially as they relate to the study of human nu­trition. After reading this article, you have a brief outline on the information that is most essential about human physiology. However, if you are really interested in learning more about this subject, then you are more than welcome to start looking some other sources of information, including medical journals and other medicine books. Be sure to try to relate the information you read to your daily habits involving nutrition so that you can be healthier.