1. Photosynthesis and Cellular Respiration
Cellular Energy
Photosynthesis and
Cellular Respiration

2. Introduction
Every living thing, plants, animals, needs energy to do work which must be stored for use at any time

3. Energy is stored in molecule called Adenosine triphosphate or ATP
Composed of one adenosine molecule and three phosphate groups
Adenosine P

4. phosphate groups (PO4 3-) are negatively charged
opposites attract, but LIKES REPEL! Phosphate groups HATE being attached to each other, so energy is stored in that hateful bond

5. when bond between phosphate #2 and phosphate #3 is broken, lots of energy is released which is then used by cell
now is called adenosine diphosphate or ADP
Energy
Adenosine P P P

8. Process of using energy from food is called cellular respiration
Both plants and animals use cellular respiration to get their energy from food, but how they obtain their food is different
Plants – sun
Animals – plants or other animals

9. Plants: autotrophs that use photosynthesis (food made using sunlight)
Animals: heterotrophs that ingest or eat (metabolism)

10. Primary Producer (autotrophs)
Transfer of energy can be presented in a pyramid
Each level only gets % of energy from previous level!
Ex: primary consumer only gets 1% of sun’s energy
Quaternary Consumer (h)
Tertiary Consumer (h)
Secondary Consumer (h)
Primary Consumer (heterotroph)
Primary Producer (autotrophs)
0.001%
0.01%
decomposers
0.1% 1%
10%
100%

11. Homework
p. 96 #1-6

12. Photosynthesis
Complex process in which visible sunlight (ROY G. BIV) is converted into chemical energy in carbohydrate (glucose) molecules

13. Process occurs within chloroplasts of plant cell

14. Divided into 3 stages that occur in only two areas of chloroplast:
Thylakoid membrane (light-dependent reaction: first two stages)
Stroma (light-independent reaction: last stage)

15. Chloroplast

16. Thylakoid in chloroplast
Light-dependent reaction (thylakoid)
1. Absorption of light energy
Thylakoid in chloroplast contains pigments chlorophyll and carotenoids
Water molecules split leaving H+ and O2 and freely moving excited electrons (e-)
chlorophyll O2 H+
H2O e-
carotenoids
Thylakoid in chloroplast

17. Step 1 End Results H+ (hydrogen ion): from splitting water
O2 (oxygen): from splitting water
e- (electron): in everything, including chloroplasts

18. ETC e- e- e- e- e- e- e- e- e- e- 2. Conversion of light energy
Excited e- pass through series of molecules along thylakoid membrane called electron transport chain (ETC) e- e- e- e- e- e- e- e- e- e-
ETC

19. Causes H+ to be pumped into thylakoid lumen AGAINST concentration gradient
Of course, H+ will diffuse out of thylakoid DOWN gradient making ATP H+ H+ H+ H+ H+ H+ H+ H+ H+

20. ETC H+ H+ H+ H+ NADPH e- NADPH e- NADPH e- e- e- e- e-
Different ETC binds H+ with NADP+ (e- acceptor) forming NADPH
Forms ATP needed for energy in next steps H+ H+
NADP+
NADPH
NADP+ e-
NADP+
NADPH H+ e-
NADPH H+ e-
ATP!! e- e- e- e-
ETC

22. Step 2 End Results NADPH: needed for next step
ATP: energy needed for next step

23. + +  + + End Results (1 & 2 so far…)
Sunlight + H2O + NADP+  NADPH + ATP + O2 (into atmosphere)
NADP+ + + 
ATP!! O2 +
NADPH +

24. + +  CO2 + NADPH + ATP  glucose Light-independent reaction (stroma)
3. Storage of energy (Calvin Cycle)
CO2 from atmosphere enters stroma, plus NADPH, plus ATP with enzyme makes glucose
Process called Calvin cycle
Carbon fixation (from gas to solid)
 CO2 + NADPH + ATP  glucose
CO2
ATP!! + +
NADPH 

26. O H O H C O H C C H H H H O H C C H O C O H H H
GLUCOSE O H
C6H12O6 O H C O H C C H H H H O H C C H O C O H H H

27. Overview of Photosynthesis

28. Overview of Photosynthesis

30. 6CO2 + 6H2O + sunlight  C6H12O6 + 6O2
Photosynthesis
Stage
Light
Location
Start Products
End Products
Absorption of Light
Dependent
Thylakoid of chloroplast
H2O, CO2, light
H+, O2, electrons
Conversion of light (ETC)
Thylakoid membrane of chloroplast
H+, NADP
ATP, NADPH
Storage of energy (Calvin Cycle)
Independent
Stroma of chloroplast
CO2, NADPH, ATP
Glucose (C6H12O6) 1 2 3
6CO2 + 6H2O + sunlight  C6H12O6 + 6O2

31. Environmental factors can affect rate of photosynthesis
CO2
H2O
Sunlight
Temperature (enzymes can get degraded with excess)
CO2

33. Homework
P. 103 #1-6

34. Cellular Respiration
Three stages that occur in different parts of cell:
1. Anaerobic glycolysis (cytoplasm)
2. Aerobic Krebs cycle (mitochondria matrix)
3. Aerobic electron transport chain (cristae of mitochondria)

35. Glucose  2 ATP + 2 pyruvate
1.Glycolysis
Enzyme-assisted anaerobic (without oxygen) process of breaking down glucose into 2 ATP + 2 pyruvate
Glucose  2 ATP + 2 pyruvate
ATP  +
pyruvate
ATP
pyruvate

36. 2. Krebs cycle (AKA citric acid cycle)
Aerobic (with oxygen) process of making 2 ATP + e-
Pyruvate + O2 makes 2 ATP
If oxygen is absent, pyruvate gets converted to lactate (in muscles) or ethanol (in plants) in process called fermentation

38. Lactate or lactic acid can build up in muscle cells during vigorous anaerobic exercise, and if not removed quickly enough by blood, can cause muscle cramps and/or soreness
Ethanol (drinking alcohol) can build up in plants along with CO2
Pyruvate + O2  2ATP O2
ATP  +
pyruvate

40. 3. Electron transport chain (ETC)
Additional ETC makes (on average) 32 ATP
e-  32 ATP!
ATP
ATP
ATP
ATP
ATP
ATP e-
ATP
ATP e-
ATP e-
ATP e-
ATP e- e- e-
ATP
ATP
ATP
ATP
ATP
ATP

41. glucose 1
pyruvate 3 2

42. Cellular Respiration

43. Cellular Respiration C6H12O6+ 6O2  6CO2 + 6H2O + 36 ATP O2 1 2 3
Stage
Oxygen Presence
Location
Start Products
End Products
Glycolysis
Anaerobic
Cytoplasm
C6H12O6
2 ATP,
2 pyruvate
Citric acid (Krebs) cycle
Aerobic
Mitochondria
O2,
2 ATP, 6CO2, e-
Lactic Acid Fermentation (animals)
Lactic acid,
2 ATP, e-
Alcohol Fermentation (plants)
Alcohol,
Electron Transport Chain (ETC)
Cristae of mitochondria e-
32 ATP, 6H2O 1 2 3
C6H12O6+ 6O2  6CO2 + 6H2O + 36 ATP

44. Photosynthesis & Respiration

46. Homework
P. 110 #1-6

47. Classwork
p. 112 #1-12
p. 113 #1-7

48. THE END