1. Photosynthesis

2. Cellular Respiration

3. 6CO2 + 6H2O  C6H12O6 + 6O2 Photosynthesis
Carbon dioxide + water  glucose + oxygen

4. Chloroplast

6. ATP
Adenosine Triphosphate

8. ATP & ADP ATP: Adenosine triphosphate adenine + ribose + 3 phosphates
Energy storing molecule
Source of all cell energy
When one phosphate group breaks off, energy is released
ADP = Adenosine Diphosphate
Adenine
3 Phosphate groups
Ribose

9. ADP: Adenosine diphosphate Adenine + ribose + 2 phosphates
Molecule that results from ATP losing one P
Another P may be added later
ADP
ATP
Energy
Energy
Adenosine diphosphate (ADP) + Phosphate
Adenosine triphosphate (ATP)
Partially
charged
battery
Fully
charged
battery

10. Overview Photosynthesis
Photosynthesis: process using energy from sunlight to convert water and CO2  carbohydrates (glucose) & oxygen
Two parts:
Light dependent reactions: produce O2 & converts ADP to ATP
Calvin cycle (dark reactions), Light independent reactions: use ATP from light reactions to produce sugar
Light Energy
Chloroplast
CO2 + H2O
Sugars + O2

11. Moves energy to electrons that drive reactions
Chlorophyll: green pigment in cells that absorbs blue & red light energy (does NOT absorb light in the green area of the spectrum)
Moves energy to electrons that drive reactions
FORMULA:
6CO2 + 6H2O  C6H12O6 + 6O2
Sugars
Chloroplast
Light-
Dependent
Reactions
Calvin
Cycle

12. Chloroplast

13. Thylakoid: saclike photosynthetic membranes arranged in stacks called granum
Stroma = area outside the thylakoid membrane
Light Dependent Reaction: thylakoid
Light Independent Reaction aka Calvin Cycle: Stroma

14. Light Dependent Reaction

15. Photosystem II Happens first (but was discovered after Photosystem I)
E (from light) is absorbed by e
These high E electrons are passed on to the electron transport chain
H2O molecules are broken into 2H+, 1 oxygen molecule, and 2 electrons (these electrons are then used at the beginning of the elec trans chain)

16. Electron Transport Chain
High E electrons move through chain to Photosystem I
The E from the electrons is used to move H+ from stroma into the thylakoid

18. Photosystem I E from light is added (again) to the electrons
These high E electrons are picked up by electron carriers (NADPH+) at the outer surface of the thylakoid
NADPH+ converts to NADPH when electron is added

19. Hydrogen Ion Movement
Inside of thylakoid membrane is positively charged (result of H+ released when H2O molecule was split)
Outside of thylakoid is negatively charged (comparatively)

20. ATP Formation
The H+ ions pass through thylakoid membrane, getting “spun” by ATP synthase
This action allows ADP to convert to ATP

21. Calvin Cycle aka Light Independent Cycle

22. 6CO2 enter(from atmosphere) combining with 6 5-carbon molecules
Yield = 12 3-carbon molecules

23. E from ATP and the high E electrons in NADPH convert the 12 3-carbon molecules to high E molecules
ATPADP
NADPHNADP+

24. 2/12 of 3-carbon molecules are used to form various 6-carbon sugars

25. Remaining (10) 3-carbon molecules re-enter the cycle as 6 5-carbon molecules

28. Van Helmont (1643)

29. Priestley (1771)

30. Ingenhousz (1779)

32. What affects photosynthesis?
Water shortage
Intensity of light
Temperature
CO2

33. Cellular Respiration
Process that releases E by breaking down glucose in the presence of oxygen

34. Cellular Respiration

36. Glycolysis Begins this process
If O2 present: leads to 2 pathways that release a lot of E
If O2 not present: a different pathway is followed
Glycolysis: happens in cytoplasm
Krebs Cycle: happens in mitochondrion
Electron Transport Chain: mitochondrion

37. If Oxygen is Present:
Glycolysis is followed by Krebs cycle and the electron transport chain
Glycolysis/Krebs Cycle/Electron Transport= Cellular Respiration
Oxygen + Glucose  Carbon Dioxide + Water + ENERGY

38. Glycolysis 1st set of reactions in cellular respiration
1 molecule of glucose is broken in half yielding 2 molecules of pyruvic acid
Needs 2 ATPs to get started; yields 4 ATPs
Net gain of 2 ATPs

39. Glycolysis
Removes 4 high E electrons and passes them to NAD+ (an electron carrier)
Thousands of ATPs produced in milliseconds in cells
No oxygen required
NAD+ get filled up with electrons so ATP production stops

40. Krebs Cycle aka Citric Acid Cycle
Occurs in mitochondrion
Pyruvic acid (from glycolysis) is used to make CO2
NADH, ATP, FADH2 also produced

41. Krebs Cycle Begins when pyruvic acid enters mitochondrion
One C removed (forming CO2 )
Citric Acid is formed
Citric Acid then broken down
More CO2 is released
1 ATP is formed
4NADH & 1FADH2 also formed (electron carrier molecules)

42. Electron Transport Chain
Uses the high E electrons from the Krebs Cycle to convert ADP  ATP
NADH & FADH2 passed into/along the e transport chain
High E electrons help transport H+ ions across the membranes affect the charge inside/outside the membrane
Enzymes help attach a phosphate to ADP, converting ADP  ATP

45. What happens to pyruvic acid during Krebs Cycle?
It’s broken down into CO2 in a series of energy extracting reactions
How does the e transport chain use the high E electrons from Krebs cycle?
To convert ADP  ATP
Why is cellular respiration more efficient than Krebs Cycle alone?
34 (additional) ATPs produced in Cellular Respiration/2 ATPs produced in Glycolysis

46. What happens if no O2 is available?
Fermentation (anaerobic)
Alcoholic Fermentation
Yeasts and other microorganisms
Forms ethyl alcohol & CO2 as wastes
Forms “bubbles” in bread

47. What happens if no O2 is available?
Lactic Acid Fermentation (anaerobic)
Forms lactic acid as waste
Causes “burn” in muscles
Creates “oxygen debt”

48. Photosynthesis & Cellular Respiration