Respiration

• What is the waste product released during aerobic respiration?

  Carbon dioxide
• Why is a large amount of energy released during aerobic respiration?

  Hydrogen is reunited with atmospheric oxygen
• Where does glycolysis occur in the cell?

  Cytoplasm
• What are the products of glycolysis from one molecule of glucose?

  2 ATP, 2 NADH, 2 pyruvate
• What happens to pyruvate in anaerobic respiration?

  Converted into lactate with the help of NADH
• Where does the link reaction take place?

  Mitochondria
• What is the role of decarboxylase in the link reaction?

  Removes a molecule of CO2
• What is formed when acetate combines with coenzyme A?

  Acetyl coenzyme A
• Where does the Krebs cycle occur?

  Matrix of the mitochondria
• How many ATP molecules are produced per glucose molecule in the Krebs cycle?

  2 ATP
• Why does the Krebs cycle turn twice per molecule of glucose?

  Because two molecules of acetyl coenzyme A are formed
• What is the final electron acceptor in oxidative phosphorylation?

  Oxygen
• What is the role of the proton gradient in oxidative phosphorylation?

  Provides energy for ATP synthase to produce ATP
• How many protons are pumped across per hydrogen released by NADH?

  4 protons
• What happens to the electrons after they are passed down the electron transport chain?

  Accepted by oxygen to form water
• What is the name of the protein channel through which protons move back into the mitochondrial matrix?

  Stalked particle
• What is the significance of the proton motive force in oxidative phosphorylation?

  Provides energy for ATP synthase to produce ATP
• What are the steps of oxidative phosphorylation?

  1. NADH and FADH release protons and electrons
  2. Electrons pass through protein complexes (I to IV)
  3. Protons are pumped into the intermembrane space
  4. Electrons combine with oxygen to form water
  5. Proton gradient drives ATP synthesis via ATP synthase
• What are the key differences between aerobic and anaerobic respiration?

  Aerobic respiration:

  • Requires oxygen
  • Produces carbon dioxide and water
  • Generates a large amount of ATP

  
  

  Anaerobic respiration:

  • Occurs in the absence of oxygen
  • Produces lactate (in animals) or ethanol (in yeast)
  • Generates a small amount of ATP
• What are the main products of the Krebs cycle per glucose molecule?

  • 2 ATP
  • 6 NADH
  • 2 FADH
  • 4 CO2
• What is the role of NADH and FADH in oxidative phosphorylation?

  • NADH and FADH donate electrons to the electron transport chain
  • Electrons are used to pump protons into the intermembrane space
  • Protons create a gradient that drives ATP synthesis
• What is the overall process of glycolysis?

  • Glucose is phosphorylated and split into two molecules of pyruvate
  • Produces 2 ATP (net) and 2 NADH
  • Occurs in the cytoplasm
• What is the role of the link reaction in respiration?

  • Converts pyruvate into acetyl coenzyme A
  • Releases CO2 and reduces NAD
  • Occurs in the mitochondria
• What is the significance of the Krebs cycle in respiration?

  • Regenerates the 4-carbon molecule to accept more acetate
  • Produces ATP, NADH, FADH, and CO2
  • Occurs in the mitochondrial matrix
• What is the role of ATP synthase in oxidative phosphorylation?

  • Uses the proton motive force to synthesize ATP
  • Converts ADP and inorganic phosphate into ATP
  • Located in the inner mitochondrial membrane
• What is the significance of the electron transport chain in oxidative phosphorylation?

  • Transfers electrons through a series of protein complexes
  • Energy from electrons is used to pump protons
  • Creates a proton gradient that drives ATP synthesis
• What is the role of oxygen in oxidative phosphorylation?

  • Acts as the final electron acceptor
  • Combines with electrons and protons to form water
  • Essential for the continuation of the electron transport chain
• What is the significance of the proton gradient in oxidative phosphorylation?

  • Created by the pumping of protons into the intermembrane space
  • Provides the energy needed for ATP synthase to produce ATP
  • Essential for the synthesis of ATP in the mitochondria
• What is the role of coenzyme A in the link reaction?

  • Combines with acetate to form acetyl coenzyme A
  • Essential for the entry of acetate into the Krebs cycle
  • Plays a key role in the metabolism of carbohydrates
• What is the significance of the stalked particle in oxidative phosphorylation?

  • Acts as a protein channel for protons to move back into the mitochondrial matrix
  • Essential for the generation of ATP by ATP synthase
  • Plays a key role in maintaining the proton gradient
• What is the role of the mitochondrial matrix in respiration?

  • Site of the Krebs cycle
  • Contains enzymes necessary for the link reaction and Krebs cycle
  • Plays a key role in the production of ATP
• What is the role of the intermembrane space in oxidative phosphorylation?

  • Site where protons are pumped to create a gradient
  • Essential for the generation of ATP by ATP synthase
  • Plays a key role in the electron transport chain
• What is the role of the inner mitochondrial membrane in oxidative phosphorylation?

  • Contains the electron transport chain and ATP synthase
  • Essential for the generation of ATP
  • Plays a key role in maintaining the proton gradient
• What is the role of the outer mitochondrial membrane in respiration?

  • Acts as a barrier to separate the mitochondria from the cytoplasm
  • Contains porins that allow the passage of small molecules
  • Plays a key role in the transport of metabolites
• What is the role of the cytoplasm in respiration?

  • Site of glycolysis
  • Contains enzymes necessary for the breakdown of glucose
  • Plays a key role in the initial stages of respiration
• What is the role of the liver in anaerobic respiration?

  • Converts lactate back into pyruvate
  • Plays a key role in the Cori cycle
  • Essential for the removal of lactate from the blood
• What is the role of the Cori cycle in anaerobic respiration?

  • Converts lactate produced in muscles back into glucose in the liver
  • Plays a key role in the recycling of lactate
  • Essential for the maintenance of glucose levels during anaerobic respiration
• What is the role of the electron transport chain in oxidative phosphorylation?

  • Transfers electrons through a series of protein complexes
  • Energy from electrons is used to pump protons
  • Creates a proton gradient that drives ATP synthesis
• What is the role of the proton motive force in oxidative phosphorylation?

  • Provides the energy needed for ATP synthase to produce ATP
  • Created by the pumping of protons into the intermembrane space
  • Essential for the synthesis of ATP in the mitochondria
• What is the role of ATP synthase in oxidative phosphorylation?

  • Uses the proton motive force to synthesize ATP
  • Converts ADP and inorganic phosphate into ATP
  • Located in the inner mitochondrial membrane