the Krebs cycle

• 1. Acetyl CoA combines with 4C molecule to form a 6C molecule and the COA returns to the link reaction

  A) 4 carbon molecule

  B) 6 carbon molecule

  C) acetyl COA

  D) COA

  
• 2. This molecule is decarboxylated to a 5C molecule and CO2 is released 

  A) 6 carbon molecule

  B) 5 carbon molecule

  C) CO2

  
• In total, three turns of the citric acid cycle generate six molecules of NADH + H+ and two molecules of FADH2.
• 3. NAD is reduced 

  A) NAD

  B) NADH

  
• 4. The 5C molecule is decarboxylated again to a 4C molecule and another CO2 is released 

  A) 5 carbon molecule

  B) 4 carbon molecule

  C) CO2

  
• 5. Another NAD is reduced 

  A) NAD

  B) NADH

  
• 6. The 4C compound is converted to a new 4C compound 
• 7. ATP is made, NAD is reduced and FAD is reduced 

  A) ADP

  B) ATP

  C) FAD

  D) FADH

  E) NAD

  F) NADH

  
• 8. This is converted back to the original 4C molecule

   

  A) original 4 carbon molecule

  
• Other respiratory substances include the breakdown of lipids and amino acids which enter the Krebs cycle. 
• Glucose is not a substrate for the Krebs cycle because its broken down in glycolysis and glucose cannot cross mitochondrial membranes.