1. Photosynthesis & Respiration
Intro Video:

2. (Photosynthesis and Respiration)
Cell Energy
(Photosynthesis and Respiration)
Energy:
Energy for living things comes from food. Originally, the energy in food comes from the sun.

3. Organisms that use light energy from the sun to produce food—autotrophs (auto = self)
Ex: plants and some microorganisms (some bacteria and protists)

4. Organisms that CANNOT use the sun’s energy to make food—heterotrophs - must eat their food
Ex: animals and most microorganisms

5. Cells usable source of energy is called ATP
Cell Energy:
Cells usable source of energy is called ATP
ATP stands for adenosine triphosphate
Adenine
Ribose
3 Phosphate groups

6. ADP stands for adenosine diphosphate
Adenine
Ribose
2 Phosphate groups

7. All energy is stored in the bonds of compounds—breaking the bond releases the energy
When the cell has energy available it can store this energy by adding a phosphate group to ADP, producing ATP

8. ATP is converted into ADP by breaking the bond between the second and third phosphate groups and releasing energy for cellular processes.

9. Photosynthesis:
Photosynthesis is the process by which the energy of sunlight is converted into the chemical energy of glucose

10. Photosynthesis occurs in the chloroplasts of plants

11. Light absorbing compound is a pigment
pigments absorb some wavelengths of light and reflect others
the color our eyes see is the color that the pigment reflects

12. Chlorophyll is the pigment inside the chloroplast the absorbs light for photosynthesis
As the chlorophyll in leaves decays in the autumn, the green color fades and is replaced by the oranges and reds of carotenoids.

13. General formula for photosynthesis:
sunlight
carbon dioxide + water —> glucose + oxygen
sunlight
6CO H2O —> C6H12O O2

14. Reactants Diagram H2O CO2 Light Chloroplast C6H12O6 Glucose O2
NADP
ADP + P
Light
Dependent Reaction
Calvin Cycle
ATP
NADPH
Chloroplast
C6H12O6
Glucose O2
Products

15. Light Reaction
Takes place in the thylakoid membrane (contains chlorophyll)
Reactants needed for the light reaction:
Water, Light, ADP, NADP
Products made from light reaction and USED in dark reaction:
ATP energy to make sugar
NADPH supplies e- and H to make C6H12O6
Oxygen is released into the air

16. Dark Reaction - Calvin Cycle
Takes place in the stroma
Reactants needed for the dark reaction:
CO2, ATP, NADPH
Products made from the dark reaction used in light reaction are:
ADP returned to the light reaction to make more ATP
NADPreturns to the light reaction to pick up more electrons and Hydrogens
Glucose is made in the dark reaction for use throughout the
organism.

17. Summary:
Light Reaction—H2O is broken down and light energy is stored temporarily in ATP and NADPH. Oxygen released.
Calvin Cycle—energy is transferred from ATP and NADPH to the organic compound glucose

18. Location Reactants Products Release H2O Light Reaction thylakoid Light
ADP and NADP from dark reaction
ATP – energy to make sugar
NADPH – electrons and Hydrogen to make glucose
O2 to the air
Dark Reaction – Calvin Cycle
stroma
CO2
ATP and NADPH from light reaction
ADP and NADP back to light reaction
GLUCOSE

19. Video - photosynthesis

20. Cellular Respiration
Process where energy of glucose is released in the cell to be used for life processes (movement, breathing, blood circulation, etc…)

21. Respiration occurs in ALL cells
Takes place in the mitochondria
Can take place either with or without oxygen present.

22. Glucose Glycolysis ATP Pyruvic Acid Aerobic Fermentation RespirationNo
Oxygen
Oxygen
Aerobic
Respiration
Fermentation
(anaerobic)
Lactic Acid
Ethyl
Alcohol
ATP

23. Aerobic Respiration: Makes 38 ATP requires oxygen
Formula
C6H12O O CO H2O + 38 ATP
glucose + oxygen carbon dioxide + water + energy
Human cells contain a specialized structure – the mitochondrion – that generates energy.

24. Intro video - respiration

25. STEP 1: Glycolysis
First pathway of respiration - ALL organisms perform this
Takes place in the cytoplasm on enzymes
Splits glucose in half to form pyruvic acid or pyrates
Gives off enough energy to make 2 ATP

26. STEP 3: Electron Transport Chain
STEP 2: Krebs Cycle
pyruvic acid is broken down into carbon dioxide
Occurs in matrix of mitochondria
STEP 3: Electron Transport Chain
electrons from Krebs Cycle converts ADP into ATP
Occurs along inner membrane of mitochondria

27. Electron Transport Chain
Diagram - Cellular Respiration
Electrons carried in NADH
Mitochondria
In Cytoplasm
electrons carried in NADH
Krebs Cycle
Electron Transport Chain
Glucose
Glycolysis 2 2 34

28. Video on aerobic respiration:

29. Anaerobic Respiration or Fermentation:
pathway organisms use when no oxygen is available to the cell
Mostly unicellular organisms (low energy requirement)
Goes through glycolysis and makes 2 ATP (in cytoplasm)
2 kinds: Alcoholic and Lactic Acid

30. Lactic Acid Fermentation
pyruvic acid lactic acid+carbon dioxide
Performed by muscle cells
Lactic acid is produced in the muscles during rapid exercise when the body cannot supply enough oxygen to the tissues—causes burning sensation in muscles

31. Lactic Acid Fermentation

32. Alcohol fermentation Pyruvic ethyl alcohol+carbon dioxide acid
occurs in bacteria and yeast
Process used by baking and brewing industry
yeast produces CO2 gas during fermentation to make dough rise and gives bread its holes

33. CYCLE! Photosynthesis and Respiration
Products of one reaction are the reactants of the other (and vice versa)
CYCLE!

34. Ecological Level
Energy Flow: Producers photosynthesize and provide glucose for consumers
Carbon Cycle: Producers remove CO2 from atmosphere while consumer replaces CO2 during respiration
Water Cycle: Producers take water out of ecosystem and consumers produce water during respiration (also O2 removed by producer and returned by consumer)

35. Importance of ATP!
1. ALL organisms release ATP from break down of glucose during cellular respiration
2. ATP powers the activities of the cell and allows living things to do work
3. ATP/ADP is cycle that releases/stores energy for cell processes
4. ATP is used to actively transport material across the cell membrane

36. Cells require a constant source of energy for life processes but keep only a small amount of ATP on hand.
Cells can regenerate ATP as needed by using the energy stored in foods like glucose.
The energy stored in glucose by photosynthesis is released by cellular respiration and repackaged into the energy of ATP.