1. ATP, Photosynthesis, and Cellular Respiration: Energy in a Cell

2. I. Background information A. What is energy? --the ability to do work B. Why is it needed? --Cells need energy to maintain homeostasis and carry out life functions.

3. C. Heterotrophs get energy from _______. Ex: animals, fungi, some protists, some bacteria D. Autotrophs get energy by __________. Ex: plants, some protists, some bacteria

4. E. The chemical bonds in food are broken down to release the chemical energy stored in them. F. However, NOT all of the energy is used at once. Some of it has to be stored.

5. ATP II. ATP—adenosine triphosphate— an energy-storing molecule phosphate bonds ATP is made of: 3 phosphates 1 sugar 1 adenine

6. A. Energy is stored in the phosphate bonds. B. Energy is released when the phosphate bonds are broken.

7. C. When energy is released from ATP, a phosphate is released and ADP is left. ADP D. ADP—adenosine diphosphate ADP is made of: 2 phosphates 1 sugar 1 adenine

8. Let’s look at this reversible reaction in 3 different ways…

9. ATP ADP + phosphate + energy ATP energy ADP + phosphate

10. ++ energy ADP + phosphate + energy ATP

11. III. Photosynthesis photo—means light synthesis—means to make *Photosynthesis is the process in which autotrophs use light energy to make food.

12. Chemosynthesis bacteriainorganic compounds *Chemosynthesis is a similar process in which some bacteria use inorganic compounds to make food. chemo—means chemical

13. *Equation for Photosynthesis: CO 2 + H 2 O light energy C 6 H 12 O 6 + O 2 carbon dioxide + water light energy glucose + oxygen Note: Chemical equation at top Word equation on bottom

14. A. Where does photosynthesis take place? chloroplasts chlorophyll 1. in the chloroplasts, which contain the green pigment chlorophyll leaves 2. In plants it mainly occurs in the leaves.

16. B. Requirements for Photosynthesis: 1. water (H 2 O) 2. carbon dioxide (CO 2 ) 3. sunlight (or light energy) 4. chlorophyll (which is already present in the plant)

17. Stoma (stomata- plural) of a leaf

18. C. Products: glucose 1. Main Product—glucose (C 6 H 12 O 6 ) oxygen 2. Waste Product or by-product— oxygen (O 2 )

19. D. Two Stages: Light reactions 1. Light reactions (light-dependent)- --involves Photosystem I and II a. Chlorophyll absorbs light energy and uses it to split water. b. photolysis—splitting of water c. Take place in the grana or thylakoids

20. Chloroplast Structure

21. Dark reactions or Calvin Cycle 2. Dark reactions or Calvin Cycle (light-independent; Calvin- Benson Cycle) a. Do NOT require light! b. Glucose is produced. c. Take place in the stroma

22. Overview of Photosynthesis

23. IV. Cellular Respiration *a process in which organisms (heterotrophs AND autotrophs) break down food to release energy *There are 2 types of respiration: aerobic – using Oxygen anaerobic – Not using Oxygen

25. *Equation for Aerobic Respiration: C 6 H 12 O 6 + O 2 CO 2 + H 2 O + ATP glucose + oxygen carbon dioxide + water + energy

26. Mitochondrion Structure

27. Mitochondrion

28. 1. Aerobic respiration involves 3 processes: a. glycolysis—splitting of glucose - doesn’t require oxygen cytoplasm - occurs in the cytoplasm - - 2 ATPs to start, produces 4 ATP = Net’s 2ATP - produces 2 Pyruvate molecules

29. b. citric acid cycle (Krebs cycle) - 2 pyruvate enter - in Matrix of Mitochondria - CO2 waste product - small amounts of ATP, FADH, NADH produced c. electron transport chain - inner membrane of Mitochondria - Go In: O 2 and Energy Carrying molecules - Water, Heat, and 34 – 36 ATP produced TOTAL ATP: Glycolysis (2) + ETC (34) = 36 ATP!

30. 2. Anaerobic Respiration Does NOT require oxygen 1. Does NOT require oxygen 2 ATP’s total 2. Produces only 2 ATP’s total cytoplasm 3. Takes place in the cytoplasm fermentation 4. Also called fermentation Begins with glycolysis 5. Begins with glycolysis

31. C. Types of Fermentation (Anaerobic Respiration): Lactic acid fermentation 1. Lactic acid fermentation— a. takes place in animals Lactic acid b. Lactic acid is the waste product. c. Lactic acid builds up in muscles, causing muscle fatigue.

32. Alcoholic fermentation 2. Alcoholic fermentation— a. takes place in some microorganisms such as yeast Ethyl alcohol carbon dioxide b. Ethyl alcohol and carbon dioxide are the waste products. c. Process used in making alcoholic beverages

33. D. Both types of Respiration: Main product=energy (ATP) E. For Aerobic: Waste products=carbon dioxide and water

34. F. Contrasting Table CategoryPhotosynthesisRespiration OrganelleChloroplastMitochondrion EnergyRequiredProduced Glucose (food)ProducedRequired OxygenProducedRequired Carbon dioxideRequiredProduced