1. Chapter 4.1 Energy and Life

2. Energy is the ability to do work!
What is energy?
Energy is the ability to do work!

3. Sunlight is the main energy source for life on Earth.

4. 1. Cells use chemical energy in the form of a chemical compound called ATP, or adenosine triphosphate.
a. ATP contains:
i. A 5-carbon sugar called ribose
ii. A nitrogenous base called adenine
iii. Three phosphate groups
b. The bonds between the phosphate groups store and release energy

5. Energy is released when a phosphate group is removed.
ATP transfers energy from the breakdown of food molecules to cell functions.
Energy is released when a phosphate group is removed.
ADP is changed into ATP when a phosphate group is added.
phosphate removed

6. The chemical energy used for most cell processes is carried by ATP.
Molecules in food store chemical energy in their bonds.
Starch molecule
Glucose molecule

7. 3. ATP is the basic energy source of all cells

8. Organisms break down carbon-based molecules to produce ATP.
Carbohydrates are the molecules most commonly broken down to make ATP.
not stored in large amounts
up to 36 ATP from one glucose molecule
triphosphate
adenosine
diphosphate
tri=3
di=2

10. c. ATP is like a rechargable battery.
ADP
ATP
Energy
Energy
Adenosine diphosphate (ADP) + Phosphate
Adenosine triphosphate (ATP)
Partially
charged
battery
Fully
charged
battery

11. Chemical Energy and ATP: Storing Energy
Energy is stored in ATP
a. ADP, adenosine diphosphate, is similar to ATP but has two phosphate groups instead of three
b. When a cell has energy available, it can store small amounts by adding a phosphate to ADP making ATP

12. Using the energy
1. When a chemical bond between the 2nd and 3rd phosphates of ATP is broken, energy is released

13. Chemical Energy and ATP: Releasing Energy
2. ATP has enough energy to power a variety of cellular activities
A. active transport across the selectively permeable cell membrane
B. protein synthesis
C. muscle contractions
D. Propels flagella
E. Produces light in fireflies
Firefly
Escherichia coli bacterium with flagella

14. 4. ATP is a good short term energy storage that is recycled between ADP and ATP. Cells have only a small amount of ATP.
It is more efficient for cells to store energy as glucose.
When cells need energy they make ATP from ADP using energy from glucose.

15. Fats store the most energy.
80 percent of the energy in your body
about 146 ATP from a triglyceride
Proteins are least likely to be broken down to make ATP.
amino acids not usually needed for energy
about the same amount of energy as a carbohydrate

16. ADP vs. ATP

17. C A B What is the name of the molecule above?
What is the name of the part of the molecule labeled:
A? ___________________________
B? ___________________________
C? ___________________________
adenine
ribose
3 phospates

18. How does a cell get energy from this molecule?B
How does a cell get energy from this molecule?
By breaking the bond between the 2nd and 3rd phosphate. This releases the energy!!