Count Your ATP's

Introduction:

All cells require energy and energy conversions. Before the energy found in the bonds of complex carbohydrates can be used, they must be hydrolyzed or digested into monosaccharides. When the chemical bonds of these molecules are broken, their energy is released. This conversion involves the release of molecules of ATP, adenosine triphosphate. Molecules of ATP transfer much of the energy needed by organisms for metabolic processes like growing, reproducing and responding to the environment.

The process of releasing the energy from chemical bonds is known as cellular respiration.

The energy released as ATP comes from the breakdown of food. The energy in food can be stored for long periods as starch and fat, but they must be converted to ATP before it can be used. When ATP releases this energy to perform the "work" of the cell, it becomes ADP, adenosine diphosphate. Just as when a rechargeable battery runs out of energy needs to be recharged, ADP can be "recharged" (changed back to ATP) by living organisms during cellular respiration.

 

ATP Factoids

Each single yeast cell contains about 80 million molecules of ATP, each of which is regenerated every 5 seconds.

Each of our 20 or so trillion cells uses approximately 1 billion ATP molecules per minute.

To make one billion ATP molecules a minute in each cell, the average person must consume about 3000 calories every day.

Fats contain about 9 calories/gram and carbohydrates only 4 calories/gram.

When the human body consumes more potential energy than it needs to convert to ATP's, the excess is converted to fat for long-term storage.

To lose weight, consume less calories (potential energy) than you need to supply you with energy.

The re-formation of ATP occurs at about 10,000,000 times per second in each cell!

 

 

Aim: To learn about the ATP-ADP cycle.

Procedure:

1. Define cellular respiration:

2. Distinguish between anaerobic and aerobic respiration.

3. Do plants carry on aerobic or anaerobic respiration? When does it occur?

4. Give examples of organisms that carry on anaerobic respiration. (fermentation)

5. In what organelle does aerobic respiration occur?

6. Construct a molecule of APT using the materials on your desk and the templates attached to this lab.

Ø Identify the five molecules needed to construct the ATP molecule.

Ø What molecules had to be removed to connect the molecules?

Ø To what category of organic compounds does ribose belong?

Ø To what category of organic compounds does adenine belong?

7. Remove one of the phosphates. What is the name of this molecule?

8. What else is released when this phosphate is removed?

ATP ADP + __________ + _____________

9. What is this energy used for?

10. In order to put the phosphate back, what must be added?

ADP + Phosphoric Acid + _________ ATP

11. What is the source of the energy in #7?

12. List two differences between ATP and ADP.

13. Summarize: Supply the terms to explain the change using the word energy.

ATP

 

 

ADP +

                                                                        Phosphoric Acid

 

14. Anaerobic respiration is considered less efficient than aerobic respiration. Using one or more complete sentences, explain this statement using the terms ATP and chemical bond or potential energy.

 

15. The process of cellular respiration is considered to be the opposite of photosynthesis. Explain.

16. Many people confuse breathing with respiration. Clarify it for them! (Hint: be sure to include the term chemical reaction)

Models for Construction of the ATP molecule
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