Blood chemistry is defined as the sum of the substances, and the reactions that occur, in the blood. Human blood is made up of several chemical compounds and cells all dissolved or suspended in water. Acids, bases, proteins, salts and many other chemicals contribute to blood's chemical properties and characteristics. Blood chemistry tests typically look at both blood cells and non-cellular components such as small and large molecules.
Function
The function of blood chemistry is to maintain parameters compatible with life in a human. Blood is the liquid in which cells are suspended. While blood cells stay more or less confined to the blood vessels, many of the liquid components of blood and the molecules dissolved in blood move between blood vessels and the liquid surrounding the cells, notes Dr. Lauralee Sherwood in her book, "Human Physiology." As such, proper blood chemistry maintains proper cellular chemistry, which maintains life.
Features
Blood chemistry can be roughly divided into two parts: cellular components and noncellular components. Cellular components of blood chemistry include the various blood cells. Red cells carry oxygen, white cells fight infection and platelets assist in clotting. Noncellular components of blood include salts, such as sodium and potassium, proteins and enzymes that are responsible for transporting molecules through the bloodstream and assisting in chemical reactions, and other molecules such as blood sugar, note Drs. Reginald Garrett and Charles Grisham in their book, "Biochemistry."
Effects
Effects of normal blood chemistry are relatively unremarkable--normal chemistry maintains life. Abnormal blood chemistry, on the other hand, has a range of possible effects. If the red blood cell count is too low, a patient has symptoms of anemia. High or low blood sugar can be a sign of diabetes, and indicates that the cells might not be getting enough nutrition. Low electrolytes, or salts, can be the result of certain kinds of dehydration, notes Sherwood.
Misconceptions
It's common to consider blood chemistry something that the body regulates internally, but external influences also affect the composition of the blood. For instance, at high altitude, humans breathe more rapidly to get more oxygen. This, notes Dr. Gary Thibodeau in his book "Anatomy and Physiology," causes the body to lose carbon dioxide from the blood, which changes the blood's acidity. Decreasing acidity as a result of hyperventilation leads to feelings of dizziness and disorientation.
Considerations
In the absence of a disease process or significant outside influence, the body maintains blood chemistry within strict parameters. Because many disease processes, diabetes and thyroid disease among them, affect blood chemistry, physicians routinely check blood to determine the cause of patient symptoms. KidsHealth.org notes that basic blood chemistry tests give physicians information about everything from hydration level to organ function, in addition to helping them determine whether a patient has or is at risk of developing certain diseases.
References
- "Human Physiology"; Lauralee Sherwood, Ph.D.; 2004
- "Biochemistry"; Reginald Garrett, Ph.D. and Charles Grisham, Ph.D.; 2007
- "Anatomy and Physiology"; Gary Thibodeau, Ph.D.; 2007
- KidsHealth: Blood Chemistry
