Aerobic and Anaerobic Respiration - Essay Example

Respiration Introduction Respiration is the processes through which human beings obtain energy from food. This process takes place in the mitochondria, which are cellular organelles located in the cytoplasm. There are two forms of respiration; aerobic and anaerobic respiration. For aerobic respiration to take place, oxygen must be present to facilitate this process. This fact explains the reason why human ventilate. On the other hand, anaerobic respiration only occurs when there is the absence or reduced amount of oxygen in the cells (Starr & McMillan 2012, p.55). Aerobic respiration Aerobic respiration is the process through which energy is obtained from food for cellular use using oxygen. Therefore, aerobic respiration only occurs when oxygen is present. The main food product that is utilized in this process is glucose. When glucose is oxidized, there is a production of energy, carbon dioxide, and water. The released energy is the form of Adenosine Tri-Phosphate (ATP). The process of aerobic respiration can be summarized using the equation C6H12O6 + 6O2 = 6CO2 + 6H2O + Energy (ATP) (Starr & McMillan 2012, p56). There are three main stages through which aerobic respiration takes place; Glycolysis, Krebs cycle, and the Electron Transport Chain. Glycolysis This process of aerobic respiration occurs in cytosol part of the cell. During this process, glucose is oxidized partially and broken down into pyruvate, which is a 3 carbon molecule. Glycolysis produces 2 ATP molecules and 2 NADH molecules. Each NADH molecule is responsible for carrying 2 energy electrons, which are later used by the cell (Starr & McMillan 2012, p56). Krebs cycle This can be regarded as the second stage in aerobic respiration whereby the pyruvate molecule is processed to produce energy that is later stored between the bonds that hold the pyruvate molecule. The synthesized energy is released in the form of ATP (Starr & McMillan 2012, p.57). Electron Transport Chain This is the last stage in aerobic respiration. This process is responsible for releasing the energy synthesized during glycolysis and krebs cycle. The electron transport chain comprises of a network of electron carrying protein located on the inner membrane of the mitochondria. It is in this stage where electrons and protons are added to oxygen to produce water. Production of ATP occurs when protons move across the cell membrane, a process referred to as chemiosis (Starr & McMillan 2012, p57). Anaerobic respiration In times of strenuous exercises, there is consumption of high levels of energy, which implies that excess of ATP is needed. When there is insufficient oxygen the body respires anaerobically whereby glucose is broken in the absence of oxygen. In anaerobic respiration, there is no production of ATP. Instead, there is an accumulation of lactic acid, which leads to muscle fatigue. Accumulation of lactic acid brings about an oxygen debt. In a situation where oxygen becomes available, the lactic acid reverts back to pyruvic acid. In the presence of sufficient oxygen, the usual aerobic process occurs, and pyruvate is broken down to release water and carbon dioxide (Starr & McMillan 2012, p58). Nutrition, ventilation, and circulation in respiration The three processes are highly essential in the process of cellular respiration and due  tothe roles played by each process; cellular respiration cannot be complete without each process in place. Therefore, three body systems are required in order to ensure that the mitochondria functions effectively (Starr & McMillan 2012, p61). Nutrition This entails the process whereby human beings take in essential substances known as nutrients in order to survive. Nutrition can also be defined as the process through which living organisms take in food and utilize it for growth, metabolism, and repair. The main stages in the process of nutrition are ingestion, digestion, absorption, transport, assimilation, and excretion. In the process of cellular respiration, nutrition plays a vital role that ensures that respiration takes place effectively. Through the processes of digestion, the body is able to acquire essential food products that fuel all cells present in the body. The process of cellular respiration requires glucose for it to function effectively. This glucose is obtained from carbohydrates that are ingest in the process of nutrition (Starr & McMillan 2012, p61). The glucose is then assimilated into the cells where it is reduced into smaller substances that are later transported into the mitochondria for further processing. Within the mitochondria, the reduced glucose molecules are utilized in the production of energy needed for cellular functions. Production of energy utilizes oxygen present in cells. Circulation This is the other process, which has a significant role in the process of cellular respiration. Circulation refers to the process through which the heart and blood vessels transport essential substances to all parts of the body. Essential substances that are transported through the circulatory system include oxygen, carbon dioxide, and nutrients. Circulation facilitates the transportation of glucose present in the digestive system and oxygen present in the respiratory system into the cells for the production of energy. On the other hand, the circulatory system plays a crucial role in the elimination of wastes like carbon dioxide. Carbon dioxide is among the few waste products that are generated during the process of cellular respiration (Starr & McMillan 2012, p63). Ventilation This is the process through which the body exchanges air between the lungs and the atmosphere to allow for carbon dioxide and oxygen exchange in the alveoli. The lungs play a crucial role of ensuring that oxygen is available in the body. The alveoli within the lungs create an exchange region where blood circulating in blood capillaries clears off carbon dioxide and takes up oxygen. The oxygen is then transported into the cells to facilitate the process of cellular respiration. The mitochondrion picks up the oxygen to utilize it in producing energy in the form of ATP (Starr & McMillan 2012, p64). It is necessary to mention that the processes of circulation, ventilation, and nutrition highly rely on the energy produced through the process of cellular respiration. Therefore, sufficient energy should be present to ensure that this vital body process continue running smoothly. The products of nutrition, circulation, and ventilation are assimilated into the cells to initiate a series of the process that produce energy. These processes are glycolysis, which utilizes 2ATPs at the beginning and forms a net of 2ATPS at the end of the process. The second process is the krebs cycle, which is an intermediary stage before production of additional ATPs begins. The final process is the electron transport chain, which produces a net of 34ATPs (Starr & McMillan 2012, p.65). References List Starr, C. & McMillan, B. (2012). Human Biology, London, Cengage Learning. pp. 55-65. Read More