Burning food with oxygen
Aerobic respiration releases more energy.
Two ways to use pyruvate
Pyruvate can be used with oxygen or without it.
Which way do you think gives more energy to the cell?
What this lesson covers
The idea
In the mitochondria, pyruvate is broken down using oxygen into carbon dioxide and water; this aerobic respiration releases a lot more energy than anaerobic respiration.
Two ways to use pyruvate
Pyruvate can be used with oxygen or without it.
Which way do you think gives more energy to the cell?
- With oxygen
- Without oxygen
- They give exactly the same
With or without oxygen
Choose each case and watch what happens to pyruvate and how much energy is released.
A lot more energy
In the mitochondria, pyruvate can be broken down using oxygen. This process breaks up the three-carbon pyruvate molecule to give three molecules of carbon dioxide, and the other product is water. Because it takes place in the presence of air (oxygen), it is called aerobic respiration. It releases a lot more energy than anaerobic respiration.
In the mitochondria, pyruvate is broken down using oxygen into carbon dioxide and water; this aerobic respiration releases a lot more energy than anaerobic respiration.
Notes
Aerobic respiration: in the mitochondria, pyruvate is broken down using oxygen into carbon dioxide and water, releasing a lot more energy than anaerobic respiration.
Check yourself
Where does the break-down of pyruvate using oxygen take place?
What are the products when pyruvate is broken down using oxygen?
Which kind of respiration releases a lot more energy?
- In the cytoplasm. The break-down of glucose into pyruvate takes place in the cytoplasm.
- In the mitochondria — correct. Yes!
- In the chloroplasts. Chloroplasts hold chlorophyll and are where photosynthesis occurs.
- Ethanol and carbon dioxide. Those are formed in yeast during fermentation, in the absence of oxygen.
- Lactic acid. Lactic acid is formed when muscle cells lack oxygen.
- Carbon dioxide and water — correct. Yes!
- Aerobic respiration — correct. Yes!
- Anaerobic respiration. The release of energy in the aerobic process is a lot greater than in the anaerobic process.
- Both release the same energy. The release of energy in the aerobic process is a lot greater than in the anaerobic process.