Preview

Lab 5 Cellular Respiration

Powerful Essays
Open Document
Open Document
3401 Words
Grammar
Grammar
Plagiarism
Plagiarism
Writing
Writing
Score
Score
Lab 5 Cellular Respiration
Lab 5Cellular Respiration
Introduction:
Cellular respiration is an ATP-producing catabolic process in which the ultimate electron acceptor is an inorganic molecule, such as oxygen. It is the release of energy from organic compounds by metabolic chemical oxidation in the mitochondria within each cell. Carbohydrates, proteins, and fats can all be metabolized as fuel, but cellular respiration is most often described as the oxidation of glucose, as follows:
C6H12O6 + 6O2 → 6CO2 + 6H2O + 686 kilocalories of energy/mole of glucose oxidized
Cellular respiration involves glycolysis, the Krebs cycle, and the electron transport chain. Glycolysis is a catabolic pathway that occurs in the cytosol and partially oxidizes glucose into twopyruvate (3-C). The Krebs cycle is also a catabolic pathway that occurs in the mitochondrial matrix and completes glucose oxidation by breaking down apyruvate derivative (Acetyl-CoA) into carbon dioxide. These two cycles both produce a small amount of ATP by substrate-level phosphorylation and NADH by transferring electrons from substrate to
NAD+ (Krebs cycle also produces FADH2 by transferring electrons to FAD). The electron transport chain is located at the inner membrane of the mitochondrion, accepts energized electrons from reduced coenzymes that are harvested during glycolysis and Krebs cycle, and couples this exergonic slide of electrons to ATP synthesis or oxidative phosphorylation. This process produces 90% of the ATP.
Cells respond to changing metabolic needs by controlling reaction rates. Anabolic pathways are switched off when their products are in ample supply. The most common mechanism of control is feedback inhibition.
Catabolic pathways, such as glycolysis and the Krebs cycle, are controlled by regulating enzyme activity at strategic points. A key control point of catabolism is the third step of glycolysis, which is catalyzed by an allosteric enzyme, phosphofructokinase. The ratio of ATP to ADP and AMP

You May Also Find These Documents Helpful

  • Better Essays

    Cellular Energetics is the broad term that encompasses both cellular respiration and photosynthesis and refers to how energy changes and reacts within cells. Cellular respiration is the process by which cells break down sugars (ATP) in order to produce energy for other chemical reactions. Cellular respiration takes place mainly in the mitochondria and the reactants in this process are oxygen and glucose and the main product in this process is ATP as well as waste products which include carbon dioxide and water. Almost all organisms perform cellular respiration. There are two types of cellular respiration…

    • 1719 Words
    • 7 Pages
    Better Essays
  • Good Essays

    Cell Energy

    • 1140 Words
    • 5 Pages

    * Mitochondria. Glucose molecule splits in half. Then the NAD and electron carriers pick up electrons and hydrogen from carbon molecules forming NADH. The electron carriers play a major role in transporting the electrons to the reaction process within the mitochondria. A small amount of ATP is produced in the last step where for every glucose only two are made outside the Mitochondria. At the same time another energy source is produced providing larger amounts of energy, this source is called pyruvic acid. This acid enters the mitochondrion where most of the energy is removed. As it enters the carbon is removed and by-product electrons, co-enzyme a clings to the remaining two carbons making acetyl CoA. (Dickey, Reese, Simon, 2010).…

    • 1140 Words
    • 5 Pages
    Good Essays
  • Powerful Essays

    To be able to carry on metabolic processes in the cell, cells need energy. The cells can obtain their energy in different ways but the most efficient way of harvesting stored food in the cell is through cellular respiration. Cellular respiration is a catabolic pathway, which breaks down large molecules to smaller molecules, produces an energy rich molecule known as ATP (Adenosine Triphosphate) and a waste product that is released as CO2. Basically, cellular respiration is a metabolic process that releases energy from organic compounds (such as C6H12O6) by metabolic chemical oxidation in the mitochondria within each cell. Proteins, carbohydrates, and fats can all be broken down into fuel for the cell but cellular respiration is usually correlated with glucose. Cellular respiration also requires O2 to carry out its pathway, as oxygen will act as a final electron acceptor. So, the final equation that can be represented for Cellular Respiration is: C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + heat.…

    • 1940 Words
    • 8 Pages
    Powerful Essays
  • Good Essays

    SCI/230 Cell worksheet

    • 885 Words
    • 4 Pages

    The citric acid cycle begins after the first stage of glycolysis is completed. The two carbon molecules are converted into acetyl CoA compound. Two ATPs are produced per each molecule of glucose by the citric acid cycle. When these compounds are reduced, they are transported by electron carriers to the next stage. The citric acid cycle occurs only when oxygen is present in the mitochondrion after the cell splits during the first phase glycolysis.…

    • 885 Words
    • 4 Pages
    Good Essays
  • Better Essays

    GRT1 Task 4

    • 964 Words
    • 4 Pages

    -In order to make ATP (energy), glucose and fructose need to go through glycolysis and enter the Krebs cycle.…

    • 964 Words
    • 4 Pages
    Better Essays
  • Good Essays

    Metabolism in the body is a collection of chemical reactions that takes place in the body’s cells. Metabolism converts the nutrients in the food that we eat (digestive system) in to essential energy which is needed to power all the things we do, from something as…

    • 1101 Words
    • 5 Pages
    Good Essays
  • Good Essays

    During the Krebs cycle: the products of glycolysis are further broken down, generating additional ATP and the high-energy electron carrier NADH…

    • 500 Words
    • 2 Pages
    Good Essays
  • Satisfactory Essays

    They are complementary process because they both need the same components, water, energy, carbon dioxide, and glucose.…

    • 342 Words
    • 2 Pages
    Satisfactory Essays
  • Good Essays

    The Citric Acid Cycle is a series of enzyme-catalysed reactions that take place in the mitochondrial matrix of all aerobic organisms. It involves the oxidation of the acetyl group of acetyl CoA to two molecules of carbon dioxide. Each cycle produces one molecule of ATP by substrate-level phosphorylation, and reduces three molecules of NAD and one molecule of FAD for use in Oxidative Phosphorylation. The cycle is preceded by Glycolysis, which also occurs in anaerobic respiration, and the pyruvate dehydrogenase complex, which occur in the cytoplasm and the mitochondrial matrix respectively. In aerobic respiration, glycolysis breaks down one molecule of glucose and two molecules of pyruvate, and gives a net product…

    • 1383 Words
    • 6 Pages
    Good Essays
  • Good Essays

    16) The events that occur from the end of glycolysis through the first reaction of the Krebs cycle is that first pyruvic acid enters the mitochondria by removing carbon and two oxygen. Later when the carbon dioxide is removed, energy is released and NAD+ is converted into NADH. Coenzyme A then attaches to the remaining acetyl forming acetyl CO.…

    • 610 Words
    • 3 Pages
    Good Essays
  • Satisfactory Essays

    Animation: Skull week 3

    • 376 Words
    • 3 Pages

    The oxidation of glucose to pyruvate occurs through a series of steps called glycolysis .…

    • 376 Words
    • 3 Pages
    Satisfactory Essays
  • Good Essays

    Sci 230 Essay Example

    • 897 Words
    • 4 Pages

    Each of the pyruvic acid molecules will be processed in two separate citric acid cycles. Here the three carbon pyruvic acid molecule is processed to produce ATP and Carbon Dioxide molecules. This Cycle uses ATP to specifically break down the pyruvate into Acetyl Co-A. Once this goes through the cycle, limited ATP as well as more NADH are produced. This happens in the mitochondria when sufficient oxygen is present to form the Carbon Dioxide.…

    • 897 Words
    • 4 Pages
    Good Essays
  • Satisfactory Essays

    Biology Summary Guide 7.2

    • 497 Words
    • 2 Pages

    1. The Krebs Cycle is a biochemical pathway that breaks down acetyl CoA, producing CO2, hydrogen atoms and ATP.…

    • 497 Words
    • 2 Pages
    Satisfactory Essays
  • Better Essays

    Biochemistry-Metabolism

    • 1252 Words
    • 6 Pages

    the citric acid or Krebs cycle and 3) electron transport system. The glycolytic pathway or…

    • 1252 Words
    • 6 Pages
    Better Essays