Biochemistry Task 4 Essay

In a cell cycle, there are specific checkpoints between each phases caused by the occurrence of cyclin. Cyclin determines how concentration flunctuatues. If the regulation is disrupted by a decreasein cyclin, there would be no mitosis, meaning the cell cycle would continuously go thre G0 phase. However, if there is an increase

Glucagon acts on liver cells to promote breakdown of glycogen into glucose and formation of glucose from lactic acid and certain amino acids.

In contrast, there are four metabolic stages happened in cellular respiration, which are the glycolysis, the citric acid cycle, and the oxidative phosphorylation. Glycolysis occurs in the cytoplasm, in which catabolism is begun by breaking down glucose into two molecules of pyruvate. Two molecules of ATP are produced too. Some of they either enter the citric acid cycle (Krebs cycle) or the electron transport chain, or go into lactic acid cycle if there is not enough oxygen, which produces lactic acid. The citric acid cycle occurs in the mitochondrial matrix, which completes the breakdown of glucose by oxidizing a derivative of pyruvate into carbon dioxide. The citric acid cycle produced some more ATPs and other molecules called NADPH and FADPH. After this, electrons are passed to the electron transport chain through

The reaction for this process is: C6H12 O6 → 2C2H5 OH + 2CO2 + ATP This process also uses the glycolysis stage of respiration, however it can not use the Krebs cycle or electron transport as oxygen is required. Therefore without oxygen it allows cells to make small amounts of ATP.

There are two types of cellular respiration, aerobic and anaerobic. Aerobic respiration occurs when there is oxygen present and in the mitochondria (in eukaryotic cells) and the cytoplasm (in prokaryotic cells). Aerobic respiration requires oxygen; it proceeds through the Krebs cycle. The Krebs cycle is a cycle of producing carbon dioxide and water as waste products, and converting ADP to thirty-four ATPs. Anaerobic respiration is known as a process called fermentation. It occurs in the cytoplasm and molecules do not enter the mitochondria for further breakdown. This process helps to produce alcohol in yeast and plants, and lactate in animals. Only two ATPs are produced through this process. In yeast fermentation is used to make beer, wine, and whiskey.

ATP is the main energy molecule in cells and has a unique function as an energy transferor. This molecule contains nitrogenous base adenine connected to three molecules of phosphorus. The last 2 phosphates are high energy bonds. When ATP releases the terminal phosphate, energy is released while forming a new compound ADP. ADP can be remade with another phosphate to form ATP again

3) Adding less enzyme caused the reaction to proceed more slowly than when more enzyme was utilized.

One of the most significant reactions in Glycolysis is reaction one which involves the phosphorylation of glucose to form glucose-6-phosphate. Through the transfer of the hydrolysis of ATP, this supplies energy for the reaction and makes it essentially irreversible, having a negative free energy change, which allows for a spontaneous reaction in cells. Although the preparatory phase is energy consuming and uses up 2 ATP, the pay off phase synthesizes 4 molecules of ATP, with the transfer of 4e- via 2 hydride ions to 2 molecules of NAD+. Therefore, a net gain of 2 ATP is achieved through the glycolytic pathway alone. Following the glycolytic pathway, due to the absence of oxygen, as oxygen cannot be supplied fast enough to undergo aerobic respiration, the athlete will instead, undergo lactic acid fermentation. Lactic acid fermentation involves pyruvate that is formed from the glycolytic pathway to be reduced to lactate, with the aid of the enzyme, lactate dehydrogenase, while the coenzyme Nicotinamide Adenine Dinucleotide (NADH) is oxidised to NAD+. The product NAD+ then re-enters the glycolytic pathway in order to produce 2 ATP. This process of lactic acid fermentation produces 2 ATP for each cycle, and thus, rapidly supplies the body with a small amount of energy. However, with the buildup of lactic acid in the body, the athlete will eventually encounter the feeling of discomfort as this accumulation of lactate causes the body to

Aerobic respiration happens only when oxygen is presented in the cell. Aerobic respiration starts with pyruvate crossing into the mitochondria. When it passes through, a Coenzyme A will attach to it producing Acetyl CoA, CO2, and NADH. Acetyl CoA will enter into the Krebs cycle. In the Krebs cycle Acetyl CoA will bound with Oxaloacetic Acid (OAA), a four carbon molecule, producing the six carbon molecule, Citric Acid. Citric Acid will reorganize into Isocitrate. This will lose a CO2 and make a NADH turning itself into alpha ketoglutarate, a five carbon molecule. Alpha ketoglutarate will turn into an unstable four carbon molecule, which attaches to CoA making succinyl CoA. During that process a CO2 and NADH is made. An ATP is made when CoA leaves and creates Succinate. This molecule is turned into Fumarate, creating two FADH2 in the process. Then Fumarate is turned into Malate then into OAA making two NADH. Only two ATP is produced in Krebs cycle but the resulting NADHs and FADH2s are passed through an electron transport chain and ATP synthase. When the molecules passes through that cycle a total of 28 ATP molecules are produced. In all aerobic respiration produces 32 ATP and waste products of H2O and

then release the products. The principal function of enzymes is to increase the rate of the

Energy needed to function comes from the conversion of adenosine triphosphate (ATP) to adenosine diphosphate (ADP). To keep a continuous supply of ATP, ATP is resynthesized using one of the three energy pathways. The three energy pathways are the phosphagen, anaerobic and aerobic systems.

Electrons are passed between the complexes of the electron transport chain and enable the cells to generate energy. The first complex accepts the electrons that are produced from the degradation of the food we eat. As it passes the electrons to the third complex in the chain protons (positively charged hydrogen atoms) are moved across the inner mitochondrial membrane. At complex three the electrons from complex one are joined by others donated by complex two. Complex three passes these electrons onto complex four and in the process moves more protons across the inner mitochondrial membrane. Within complex four the electrons are joined to oxygen to produce water, alongside one final movement of protons. Since so many protons have now been moved across the membrane the amount of them is higher on one side of the membrane than the other, this creates a gradient. Complex five then uses this gradient to produce ATP. The proton gradient rotates this final complex and with each rotation an ATP is made. For every cycle of the electron transport chain over 30 ATPs are produced, this shows how efficient energy generation is within the

The energy system that is able to generate ATP without oxygen is called the anaerobic system. Anaerobic meaning without oxygen. This system is formed from the combination of ATP and lactic acid. The metabolic pathway of the anaerobic system is called anaerobic glycolysis. Glucose is broken down during the metabolic pathway glycolysis, with or without oxygen present. Carbohydrates are the only macronutrient that can be catabolized during glycolysis.

Gluconeogenesis is the process in which the liver predominantly forms glucose from non-carbohydrate sources such as lactate, pyruvate, glycerol and amino acids, but can also occur to a smaller extent in the kidneys. It occurs when the carbohydrate source is not sufficient enough to meet the body’s energy requirements. This process is significant in maintaining blood glucose levels occurring during periods of

Cellular respiration is a procedure that most living life forms experience to make and get chemical energy in the form of adenosine triphosphate (ATP). The energy is synthesized in three separate phases of cellular respiration: glycolysis, citrus extract cycle, and the electron transport chain. Glycolysis and the citric acid cycle are both anaerobic pathways because they do not bother with oxygen to form energy. The electron transport chain however, is aerobic due to its use of oxidative phosphorylation. Oxidative phosphorylation is the procedure in which ATP particles are created with the help of oxygen atoms (Campbell, 2009, p. 93). During which, organic food molecules are oxidized to synthesize ATP used to drive the metabolic reactions necessary to maintain the organism’s physical integrity and to support all its activities (Campbell, 2009, pp. 102-103).