Your assignment is to prepare and submit a paper on the krebs cycle and its relationship to aerobic and anaerobic metabolism & acid base balance.

Your assignment is to prepare and submit a paper on the krebs cycle and its relationship to aerobic and anaerobic metabolism & acid base balance. The Krebs cycle and its relationship to Aerobic and Anaerobic Metabolism & Acid base balance All cells are required to generate energy for survival, be it a eukaryotic or prokaryotic cell. The process involved in the production of cellular energy was defined by Hans A. Krebs in the year 1937. He proposed that the production of cellular energy is association with a particular metabolic pathway in the cells. This is called the Krebs cycle or the citric acid cycle which defines the oxidation of carbohydrates in animal tissues. Consequent to this finding it was later found that the acetyl derivation (a compound produced during fat degradation) has identical properties to the compound produced when pyruvate undergoes oxidative decarboxylation. This proves that the Krebs cycle occurs in the oxidation of fats. It was later found by Krebs that the citric acid cycles is not limited to animal cells but it takes place is almost all aerobic cells. In a cell, the Krebs cycle occurs in the mitochondria or power plant and generated energy need by the organism to function (The Krebs Cycle. Cell Structure and Function).

Krebs metabolic pathway in the cells is responsible for the oxidation of the basic food components that constitute carbohydrates, protein and fat to give out energy. Mitochondria are present in the cells of the human body. The fundamental function of these minute organelles (that range from 500 to 2000 mitochondria in a cell) is to convert energy present in the nutrient molecules and store this energy in the form of ATP (adenosine triphosphate). ATP is the universal energy producing molecules utilised by enzymes to conduct a number of cellular functions. Human being cannot live even for a second without the continuous supply of ATP. Energy conversion requires oxygen and this is supplied by the circulatory and respiratory systems which carry the oxygen to the tissue for further use by mitochondria to remove carbon dioxide. This process is called cellular respiration. During the Krebs cycle, acetyl coenzyme A is metabolised into citric acid which undergoes a complex series of biological oxidation to produce free hydrogen ions. The hydrogen ion then move to a biochemical phase called oxidative phosphorylation which is a highly competitive aerobic energy producer. Oxidative phosphorylation produces 36 molecules of ATP.

There are different phases at which metabolites move into the Krebs cycle. Components of carbohydrates, fat and protein are broken down to molecule coenzyme A before moving into the Krebs cycle. Glucose the basic fuel in the body is initially metabolized into pyruvic acid and later to acetyle coenzyme A. The Embden Meverhof pathway method of glycolysis avails the two molecules of ATP released from the metabolism of glucose. When oxygen is not available for metabolism or when the Krebs cycle is hindered the body changes its energy generation from the Embden Meverhof pathway of glycolysis. Glycolysis produces less energy and also generates lactic acid as a by-product.

Excessive lactic acid leads to acidiotic condition from several metabolic troubles. The accumulation of lactic acid in muscle tissues will lead to muscular tissue pain and inflammation. For example if Krebs cycle is inhibited by catabolic pathways like illness or stress, anaerobic metabolism of glucose takes place with pyruvate. Increase in the acid content leads to decrease in the oxygenation of tissues. Various studies have shown that continuous exercise leads to a reduction of glycogen and carbohydrates that reduces carbon compounds from glycolysis. This leads to deficiency of energy in the Krebs cycles and results in its shut down thereby decreasing the aerobic capacity (Ward & English, Cycle Intermediates).

Due to the accumulation of acid in the tissue the acid base balance of the body either increases or decreases. Increase in the acid base balance will decrease Krebs cycle oxidation in muscles and renal cortex and decrease in the acid base balance with increase Krebs cycle oxidation in muscles and renal cortex and lead to disorders in several parts of the body (Powers, Acid-Base Balance).

Works Cited

Dean,Ward & English, Jim. Krebs’ Cycle Intermediates. 2008. Available:

http://www.nutritionreview.org/library/krebs.html. Accessed on September 24, 2008.

Powers, Ann. Acid-Base Balance. 2001. Available:

repository.upenn.edu/cgi/viewcontent.cgi?filename=8&article=1003&context=miscellaneous_papers&type=additional. Accessed on September 24, 2008.

The Krebs Cycle. Cell Structure and Function. Available:

http://incolor.inetnebr.com/mcanaday/main.htm. Accessed on September 24, 2008.