Glycolysis
Which molecule is split during glycolysis?
What is glucose?
Where does the two-carbon compound which starts the Krebs cycle come from?
What is the primary goal of the electron transport chain?
What is the formation of a large amount of ATP.
What is the net gain of ATP during the glycolysis stage?
What is 2?
Where does the phosphate which binds to glucose come from?
The splitting of ATP into ADP and P.
Name the 4-carbon molecule which is recycled at the end of the Krebs cycle.
What is oxaloacetate?
How many complexes make up an electron transport chain?
What is 4?
Why are there two rounds for the Krebs cycle?
Glycolysis forms two pyruvate molecules. Each pyruvate loses CO2 resulting in acetyl CoA. Each of the two acetyl CoA undergoes one round of the Krebs cycle.
Where does glycolysis happen inside of the cell?
What is cytoplasm?
Where (inside the cell) does cellular respiration occur?
What is mitochondria?
Why is a considerable amount of energy released in complex 1?
Not only is NADH broken down, releasing energy, but the 2e- from the NADH breakdown interacts with several protein molecules resulting in multiple releases of energy.
What fraction of the total CO2 produced in cellular respiration is produced during the Krebs cycle?
Two thirds.
Two rounds of the Krebs cycle produces four CO2 molecules.
Overall 6 CO2 molecules are produced in respiration (two in the intermission between glycolysis and the Krebs cycle)
Why is the three-carbon molecule with two phosphates attached particularly unstable?
Two phosphate groups close together leads to a lot of repulsion between the negatively charged oxygen atoms on the phosphate groups.
Why is it possible to produce high-energy molecules such as NADH and FADH2 during the Krebs cycle?
Less stable molecules become more stable, releasing energy making these two processes possible:
energy + NAD+ + H+ + 2e- = NADH
energy +FAD + 2H+ + 2e- = FADH2
Why does the breakdown of NADH lead to the formation of more ATP than the breakdown of FADH2?
The 2e- from the NADH travels through one more complex containing an H+ channel than the 2e- from FADH2 resulting in more H+ being pushed out due to the breakdown of NADH. More H+ being pushed out means that more ATP will be formed when the H+ goes back inside of the mitochondria.
How many ATP typically are formed from the breakdown of one NADH molecule and one FADH2 molecule?
three ATP molecules from one NADH molecules
two ATP molecules from one FADH2 molecule
Why is glycolysis an acceptable way to obtain energy for bacteria?
Bacteria are simple organisms. Their energy needs are lower; it doesn't matter that you don't obtain much ATP from glycolysis.
How are the Krebs cycle and the Electron Transport Chain connected?
The NADH and FADH2 produced in the Krebs cycle break down during the electron transport chain. The energy released helps to make the formation of ATP from ADP and P possible because the energy released forms a high H+ gradient which is decreased during ATP formation.
Give another reason besides the release of energy why the breakdown of NADH and FADH2 is useful for respiration.
NAD+ and FAD is recycled so they can be used again for the Krebs cycle.
How many H+ combines with one O2 molecule during the electron transport chain?
4H+