2. Unit 2 Section 3 Energy Use

3. Energy is essential to life. All living organisms must be able to obtain energy from the environment in which they live. Organisms can be classified according to the origin of their energy.

4. A.Autotrophs - organisms that make their energy, via photosynthesis; All life depends on autotrophs. AKA: Producers B. Heterotrophs - organisms that must consume their energy by eating autotrophs and/or other heterotrophs. AKA: Consumers

5. I. CELLS CHEMICAL ENERGY ATP - (adenosine triphosphate) Cells energy molecule that can be used easily and quickly. - ATP molecule has two parts: adenosine (adenine + ribose) and phosphate groups  Energy is found in the bonds between the phosphate groups

6. II. Photosynthesis

7. Definition: Converts solar energy (radiant, light) into chemical energy stored as carbohydrates (sugars). Who: Autotrophic organisms Where: Chloroplast of plant cells.

8. internal leaf structure chloroplasts outer membrane inner membrane thylakoid

9. Reactants: Carbon Dioxide, water and Sunlight Products: Carbohydrates (sugar) and Oxygen Equation: 6 CO 2 + 6 H 2 O + light energy  C 6 H 12 O 6 +6 O 2

11. A. Chloroplast Organelle of plant cells Function: Site of photosynthesis Chlorophyll – pigment found in chloroplast that traps sunlight and gives plants their green color.Chlorophyll – pigment found in chloroplast that traps sunlight and gives plants their green color.

12. B. Gas Exchange Stomata – Pore of the leaf where gas exchange takes place (CO 2 and O 2 ) Closes to conserve water and opens to release water

13. Photosynthesis Summary The plant absorbs carbon dioxide from the atmosphere, draws water up through its roots and uses light to photosynthesize sugars,which it uses as food. It also excretes oxygen as a by-product of the process.

14. III. Cellular Respiration Definition: Process of synthesizing ATP by breaking down carbohydrates (organic compounds) Where: Mitochondria

15. Reactants: Carbohydrates (sugars) and Oxygen Products: Carbon Dioxide, Water and ATP Equation: C 6 H 12 O 6 + 6 O 2  6 CO 2 + 6 H 2 O + ATP

16. Cellular Respiration

17. Types: 1.Aerobic – means with oxygen – normal type of respiration that has already been described. 2.Anaerobic – means without oxygen – special type of respiration when the oxygen supply is absent.

18. COMPARISONAerobic Respiration Anaerobic Respiration Reactants Oxygen and Carbohydrates Carbohydrates ATP Large Amounts 36 total Small Amounts 2 total Types Alcoholic Fermentaion – Bacteria / Fungi Lactic Acid Fermentaion – Animal Cells Produces ATP and Carbon Dioxide Alcohol or Lactic Acid, ATP and Carbon Dioxide

19. IV. Biochemical Pathways A complex series of chemical reactions, in which the product of one reaction is consumed in the next reaction. Example: Photosynthesis Cellular Respiration 6 CO 2 + 6 H 2 O + light energy  C6H12O6 + 6 O 2 C6H12O6 + 6O 2  6 CO 2 + 6 H 2 O + ATP

20. What are we missing?

22. V.ATP-ADP CYCLE Definition: Process where energy is released from the bonds of an ATP molecule for the cells activities. Where: Mitochondria

23. How: It works by breaking off ATP’s phosphate groups which releases energy. Reactant: ATP Product: ADP (Adenosine Diphosphate) and usable ENERGY!!!! Adenine PPP High-Energy Bond

24. Although we classify organisms according to their food energy, in an indirect way all organisms get their energy from light. Why and How?

25. VI.Energy Pathway - Putting it all together - Autotrophs: Sun  Plants Chloroplast (Photosynthesis)  Carbohydrates  Mitochondria (Cellular Respiration)  ATP  ATP-ADP Cycle (Mitochondria)  USABLE ENERGY IS MADE FOR CELLS ACTIVITIES!!!!!!

26. VI.Energy Pathway - Putting it all together - Heterotrophs: Sun  Plants Chloroplast (Photosynthesis)  Carbohydrates  Heterotroph eats Autotroph (Digestion)  Carbohydrates  Mitochondria (Cellular Respiration)  ATP  ATP-ADP Cycle (Mitochondria)  USABLE ENERGY IS MADE FOR CELLS ACTIVITIES!!!!!!