1. CELL ENERGY
Energy – essential for life
* All organisms must:
1. Be able to produce energy
2. Store energy
3. Use energy

2. LIFE PROCESSES THAT NEED ENERGY
-active transport
-movement
-making proteins
-nerve transmissions
-maintaining homeostasis

3. ATP = Adenosine triphosphate (adenosine molecule & 3 phosphates)
Form of energy usable by organisms
- an energy molecule (like a candy bar, quick energy)
Energy is stored in the phosphate to phosphate bond.

4. FORMING & BREAKING DOWN ATP
Phosphate groups have negative charges (like charges repel) therefore, it takes a lot of energy to hold them together.
Likewise, when a bond is broken, a lot of energy is released.
ATP

5. HOW CELLS TAP INTO THE ENERGY STORED IN ATP
Cell proteins have a site where ATP can bind
Is released from the binding site
Breaks down into
Another phosphate may now bind there
1. ATP
ADP
Adenosine triphosphate to Adenosine diphosphate
3 phosphates  2 phosphates
*Some cell functions (that don’t require much energy) can use ADP for an energy source

6. HOW PLANTS ACQUIRE THEIR ENERGY
Autotrophic = organisms that make their own food (ex: plants)
Photosynthesis = process where plants trap light energy to make glucose.
Glucose (a carbohydrate) C6H12O6

7. THE 2 PHASES OF PHOTOSYNTHESIS
Light Energy  Chemical Energy (ATP)
Light Reactions (light dependent)
Dark Reactions (Light independent)
ATP  Glucose

8. PHOTOSYNTHESIS EQUATION
CO H2O + light energy C6H12O O2
Carbon dioxide + Water+ light energy Glucose Oxygen
6 CO2
C6H12O6
Glucose
6 O2
6 H2O

9. THE CHLOROPLAST & PIGMENTS
The site of photosynthesis is the chloroplast
Thylakoid Discs = located in the membrane of chloroplast is the site of light-dependent reactions.

10. Pigments in thylakoid discs absorb specific wavelengths of sunlight.
Why are plants green?
Chlorophyll a & b (color pigment in chloroplast) absorb most wavelengths except green, therefore, green is reflected

11. Why are fall leaves different colors?
In the fall, trees reabsorb chlorophyll & allows other pigments to be seen.

13. CELLULAR RESPIRATION
Respiration = process by which cells break down food (glucose) to get energy
Occurs in the mitochondria

14. C6H12O6 + O2  CO2 + H2O + energy Energy from photosynthesis
Heat energy
O2 released in air
CO2
Glucose stored in plants
Glucose
water
C6H12O6 + O2  CO2 + H2O + energy
(Glucose) (Oxygen) (Carbon Dioxide) (water) (ATP)

15. 3 STAGES OF CELLULAR RESPIRATION
First Phase (Anaerobic = oxygen is not required)
(1) Glycolysis – Breaks glucose down * Yields: (a) 2 ATP molecules and (b) Pyruvic acid
Occurs in the cytoplasm The glucose is small enough to enter the mitochondria and begin Phase 2

16. 2nd Phase
(Aerobic = oxygen is required)
(2) Citric Acid Cycle (or Krebs Cycle)
Yields: (a) 2 ATP molecules
And(b) acetic acid plus 24 H+ atoms

17. 3rd Phase
(Aerobic)
(3) Electron Transport Chain
* Yields: 24 H+ atoms + O2  34 ATP
CELLULAR RESPIRATION YIELDS
38 ATP MOLECULES

18. Fermentation = occurs when cells are without oxygen for a short period of time
Produces : ATP until oxygen is available.

19. 2 Types
Lactic Acid
The pyruvic acid from glycolysis becomes lactic acid & yields 2 ATP
Lactic acid in muscles makes you feel tired and sore. Strenuous exercise used up O2.

20. 2. Fermentation (Alcoholic)
Produces CO2 and ethyl alcohol and 2 ATP
Examples of how fermentation is useful:
yeast in bread (bread rises)
- Yeast ferments grapes

21. Comparisons Photosynthesis VS Respiration
1.Stores Energy
Releases Energy
2. Makes Food
Breaks Down Food
3. Uses CO2 and H2O
Uses Glucose and O2
4. Makes Glucose and O2
Makes CO2 and H2O
5. Occurs in Chloroplasts
Occurs in Mitochondria
6. Occurs only in Light
Occurs all the time, light & dark

22. Combined Equations of Photosynthesis & Respiration
CO2+ H2O + energy Glucose + O2
Respiration

23. THE END