How can hco3 act as a buffer

Manglik, C. Markham, K. Castillo, K. Mao, and R. Louis, MO Many people today are interested in exercise as a way of improving their health and physical abilities. When we exercise, our heart rate, systolic blood pressure, and cardiac output the amount of blood pumped per heart beat all increase. Blood flow to the heart, the muscles, and the skin increase. We breathe faster and deeper to supply the oxygen required by this increased metabolism. With strenuous exercise, our body's metabolism exceeds the oxygen supply and begins to use alternate biochemical processes that do not require oxygen.

These processes generate lactic acid, which enters the blood stream. As we develop a long-term habit of exercise, our cardiac output and lung capacity increase, even when we are at rest, so that we can exercise longer and harder than before. Over time, the amount of muscle in the body increases, and fat is burned as its energy is needed to help fuel the body's increased metabolism.

This figure highlights some of the major acute short-term effects on the body during exercise. During exercise, the muscles use up oxygen as they convert the chemical energy in glucose to mechanical energy. This O 2 comes from hemoglobin in the blood. These chemical changes, unless offset by other physiological functions, cause the pH of the blood to drop. If the pH of the body gets too low below pH 7. This can be very serious because many of the chemical reactions that occur in the body, especially those involving proteins, are pH-dependent.

Ideally, the pH of the blood should be maintained at 7. If the pH drops below 6. Fortunately, we have buffers in the blood to protect against large changes in pH. All cells in the body continually exchange chemicals e.

This external fluid, in turn, exchanges chemicals with the blood being pumped throughout the body. Diffusion through membrane channels is a dominant mode of exchange between these fluids cellular fluid, external fluid, and blood. The diffusion is due to a concentration gradient associated with the contents of the fluids. Hence, the chemical composition of the blood and therefore of the external fluid is extremely important for the cell.

In order to maintain the proper chemical composition inside the cells, the chemical composition of the fluids outside the cells must be kept relatively constant. This constancy is known in biology as homeostasis.

This is a schematic diagram showing the flow of species across membranes between the cells, the extracellular fluid, and the blood in the capillaries. The body has a wide array of mechanisms to maintain homeostasis in the blood and extracellular fluid.

The most important way that the pH of the blood is kept relatively constant is by buffers dissolved in the blood. Other organs help enhance the homeostatic function of the buffers. Acidosis that results from failure of the kidneys to perform this excretory function is known as metabolic acidosis.

On the other hand, acute acidosis is a condition that results from a sudden decrease in pH e. Cardiovascular Medicine. Respiratory Medicine. Gastrointestinal Medicine. Hematology and Oncology. Musculoskeletal System. Basic Concepts. Genetic Disorders. Bicarbonate Buffer. Practice: Analyzing electrocardiogram voltage signals.

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