Chemical Energy

1
Chemical Energy Trophs
2
Cellular Energy

• Cells must convert food into a form of energy
  they can use.
• They cannot cash in carbohydrates for energy
• Analogy cannot use Canadian money in the US. You
  have to convert it first.

3
Cellular Energy, continued

• Cells convert carbohydrates into ATP
• ATP (adenosine triphosphate) molecule used to
  carry chemical energy
• Carries energy in its bonds

4
Cellular Energy, continued

• The energy from ATP can power different kinds of
  work in the cell.

(a) Mechanical work
(b) Transport work
(c) Chemical work
Low concentration of solute
ATP
ADP P
ADP P
ATP
ADP P
ATP
Chlamydomonas
Enzyme
Flagella
Product
Substrates
High concentration of solute
Figure 4.12
5
How does ATP Release Energy?

• Energy is released when the last phosphate group
  is removed (bond is broken).
• ATP becomes ADP

6
How does ADP become ATP?

• Carbohydrates and other foods consumed by the
  body contain energy.
• When they are broken down, energy is released and
  is used to reattach a phosphate to ADP, turning
  it back into ATP.
• Occurs in the mitochondria

7
ATP is like a Rechargeable Battery
8
How do Organisms get carbohydrates to make ATP?

• 1. Autotrophs make their own carbohydrates using
  inorganic compounds
• Phototrophs use the sunlight for E source
• Chemotrophs use chemicals for E source
• 2. Heterotrophs eat other organisms for carbs