1. Bell Ringer Question
Large quantities of proteins modified by the Golgi apparatus exit the cell through the process of
A)diffusion.
B)endocytosis.
C)exocytosis.
D)osmosis.
What is the name of the organelle that carries the above proteins to the cell membrane?

2. Photosynthesis

3. State Objectives!
CLE Investigate the relationship between the processes of photosynthesis and cellular respiration
SPI Compare and Contrast photosynthesis and cellular respiration in terms of energy transformation.

4. Introduction: Overview
6 CO2 + 6 H2O +
light energy → C6H12O6 + 6 O2
Photosynthesis consists of two independent pathways
light-dependent reaction (light reaction)
the light-independent reaction (dark reaction).

6. Bell Ringer!!
Which is the BEST explanation for how fluid pressure from freshwater helps plants to stand upright?
A) Freshwater is a hypertonic solution, which causes the plant cells to swell with turgor pressure.
B) Freshwater is a hypotonic solution, which causes the plant cells to swell because of plasmolysis.
C) Freshwater is a hypertonic solution, which causes the plant cells to swell because of plasmolysis.
D) Freshwater is a hypotonic solution, which causes the plant cells to swell because of turgor pressure.

7. Introduction
Light Reactions: the energy in sunlight is trapped, O2 is released, and both ATP and NADPH + H+ (hydrogen-carrier molecule) are formed
Dark Reactions: the ATP and NADPH + H+ react with CO2 from the atmosphere and form glucose
The entire process results in the transformation of light energy from the sun into energy stored in the bonds of the glucose molecule.

9. Structure of a Chloroplast
The light reactions take place in the thylakoid membrane
The dark reactions take place in the stroma

10. Structure of a Chloroplast

13. Electromagnetic Spectrum

14. Why are plants green?

15. Pigments Pigments are light-absorbing compounds.
Pigments appear colored because they absorb light of certain wavelengths and reflect that of others.
Chlorophyll a is the primary pigment in green plants that absorbs red and blue/violet light and reflects green light.

16. Structure of Chlorophyll

17. Why aren’t these leaves green??

18. Accessory Pigments
Chloroplasts also contain other pigments called accessory pigments.
Accessory pigments trap wavelengths of light that cannot be absorbed by chlorophyll a and then transfer the energy to chlorophyll a molecules for use in photosynthesis. In this way, accessory pigments enable plants to use a greater amount of the sun’s energy than is available to chlorophyll alone.

22. Light Reaction

23. Light Reaction Also called Light Dependent Reaction
Pigments that are in the chloroplasts intercept light and begin the light reactions of photosynthesis.
The light reactions occur in two photosystems (located in the thylakoid membrane):
Photosystem: a unit of several hundred chlorophyll a molecules and associated acceptor molecules
-photosystem I (PSI)
-photosystem II (PSII)

24. Photosystems

25. Excited Electrons

26. NADPH
NADP+ is an electron acceptor
NADP+ + 2 e- + 2 H NADPH + H+

27. ATP Synthase

28. Bell Ringer!! Do this on socrative!
Most animal cell membranes have proteins that pump ______ ions out of the cell and potassium ions into the cell.
A) calcium
B) carbon
C) magnesium
D) sodium
NOT using socrative – draw out the light reactions of photosynthesis in as much detail as possible.

29. State Objectives!
CLE Investigate the relationship between the processes of photosynthesis and cellular respiration
SPI Compare and Contrast photosynthesis and cellular respiration in terms of energy transformation.

30. Primary Electron Acceptor ETC Proton Pump Thylakoid Lumen ATP Synthase
PSI
PSII
Thylakoid
Lumen
Water (H2O)
Oxygen (O2)
Hydrogen Ion (H+)
Electron
ATP Synthase

31. Step 1

32. Step 2

33. Step 3

34. Step 3

35. Step 3

36. Step 3

37. Step 3

38. Step 3

39. ~ e
low
high
Step 4

40. Step 4

41. Step 4

42. Step 4

43. Step 4

44. Step 4

45. Step 5

46. Step 5

47. Step 5

48. Step 5

49. Step 5

50. NADP+
NADPH
+ H+
Step 5

51. high
low
Step 6

52. Step 6

53. Step 6

54. Step 6

55. Step 6

56. ADP + P ~ e
Chemiosmosis
ATP
Step 6

57. NADP+
ADP + P
Reactants

58. O2 is
released
into the
atmosphere
NADPH
+ H+ DR
ATP
Products

60. A) microscope and digital balance
1. A student is comparing hundreds of leaves of the same tree species. The student will calculate each leaf area using a formula. The formula requires the measurements of length and width of each leaf. When all the data are collected, the student will display differences of leaves from the individual trees on a graph. Which of these tools will the student use to gather and display the data in this investigation?
A) microscope and digital balance
B) magnifying glass and hand calculator
C) metric ruler and spreadsheet program
D) Computer sensor and pie chart generator
2. What do you remember about the light reactions? C

61. Get a copy of the worksheet “Light Reactions”
The worksheet is on the computer cart
You may answer the questions at the bottom of the worksheet.

62. State Objectives!
CLE Investigate the relationship between the processes of photosynthesis and cellular respiration
SPI Compare and Contrast photosynthesis and cellular respiration in terms of energy transformation.

63. Find a Partner
Emphasize that these pathways are often very complex and explain that while the book goes into detail on many of the steps we will only focus on the inputs and outputs of the processes.

64. With your Partner: Quick Review
Where does photosynthesis happen?
Where do the light reactions happen?
What are the reactants and products of the light reactions?

65. Where does it happen? Two Stages: Light Cycle: Calvin Cycle: thylakoid
Tell the kids not to get too caught up in the NADPH and stuff. We’ll spend more time on it later. Point out that the light and calvin cycles recycle some of the molecules like ATP and NADPH.
Takes place in the stroma

66. Dark Reaction

67. Dark Reaction
The dark reaction is also known as the Calvin Cycle, after an American scientist (Melvin Calvin) who figured out the pathway.
The dark reaction is also known as the C3 Cycle because the first stable products of this pathway are molecules that contain three carbon atoms.
The Calvin Cycle occurs in the stroma.

68. Calvin Cycle Reactants: Products: CO2 – from atmosphere
ATP & NADPH – from light cycle
Sugar & other monomers for macromolecules such as amino acids (proteins) and fatty acids (lipids)

69. Calvin Cycle has 3 Parts.
1.Incorporates atmospheric CO2 into existing organic molecules (carbon fixation)
2. CO2 Reduction
3. Regeneration of RUBP

70. Calvin Cycle

71. ~ ~ 6 CO2 unstable compound 6 RuBP 6 ATP 12 PGA e 12 ATP 6 ADP + P e
10 PGAL
12 ADP + P
Glucose C
12 PGAL C
12 NADPH + H+ e-
2 PGAL C
12 NADP+

74. Write out the chemical formula for photosynthesis.
Making Connections
Write out the chemical formula for photosynthesis.
light + 6H2O + 6CO O2 + C6H12O6

75. Some Botany (Plant) Stuff
Stomata (plural) stoma (singular):
Specialized cells that create a pore in the leaves that allow air (CO2, O2, water vapor) to come and go.

76. Diffusion in Action

77. With your partner
Describe why plant cells may want to close their stoma.

78. The C4 Cycle

79. C4
vs.
CAM

80. WHY??

81. Exit Ticket
Write out the chemical formula for photosynthesis and explain where each element comes from.

82. The End!