1. Essential Question: How is photosynthesis carried out?

2. How Energy is Stored?
The first way that the energy can be stored is by NADP
This is an electron transport molecule and when the electron is added it becomes NADPH
This is a very temporary storage solution – use it or lose it
The second way is as ATP
Both these chemicals are used in the light independent reaction to create glucose which is long term storage of energy for the cell

3. ATP
This is the chemical that is used to store energy for use by plants and animals
Made of a 5 carbon sugar and three phosphate groups
A = the sugar
T = tri = 3
P = phosphate
Energy is stored on the molecule by making bonds between the sugar and the phosphates and released by breaking the bonds between the sugar and the phosphates
Starts as AMP (m=mono=1) add a little energy and get ADP (d=di=2) add a little more energy and get ATP

5. Some ATP Uses Used to fuel the membrane pumps we learned about earlier
Also used to help make proteins and other chemical messengers
Used to make animals bioluminescent (like dinoflagellate plankton)

7. Light and Pigments
Light is actually a form of energy that travels in waves
Each color has a different wavelength and therefore a different amount of energy
White light is a combination of all different wavelengths of light
Plants use different pigments to harvest this energy by attracting specific wavelengths of light
The main pigment is chlorophyll – absorbs blue green and red wavelength and reflects green wavelengths
Plants also contain accessory pigments to capture other wavelengths of light

9. Structure of a Chloroplast
Composed of sac-like membranes called thylakoids
Stacks of thylakoids are called grana
Inside the thylakoids the chlorophyll is organized into photosystems to harvest the energy from the sun
Only the light reaction occurs within the thylakoid

11. Introduction to Photosynthesis
Plants are able to transform the energy from the sun to produce the energy that allows the plants to grow and reproduce
This energy is passed onto other animals and eventually to us
Plants are the base of our food chain
The leaves of plants use the chlorophyll to attract certain wavelengths of light

13. The chemical reaction 6CO2 + 6H2O C6H12O6 + 6O2
Simply stated carbon dioxide combines with water in the presence of light to form glucose and oxygen

14. Light Dependent Reaction
The sunlight hits the photoreception area supercharging the electrons
These electrons are then converted to NADPH and ATP
These two compounds are then used in the light independent reaction

15. The Process
Light strikes the chloroplast and the energy from the sun excites the electrons in photosystem II and they move to a higher orbit
The electrons come from the splitting of water into hydrogen and oxygen
The electron is then passed on the electron transport chain to photosystem I
The initial electrons create a chemical known as NADPH
Eventually enough inside of the thylakoid membrane has a positive charge because of all the hydrogens and the outside has a negative charge
The differences in charges allows ATP to be made

16. Light-Dependent Reactions
Hydrogen
Ion Movement
Photosystem II
Chloroplast
ATP synthase
Inner
Thylakoid
Space
Thylakoid
Membrane
Stroma
Electron
Transport Chain
Photosystem I
ATP Formation

18. Light Independent Reaction
Called this because light is no longer needed
AKA the Calvin cycle
The purpose of the Calvin cycle is to create glucose for long term storage
All plant cells do both the light dependent and the light independent reactions
The independent reaction cannot occur without the light dependent reaction

19. Calvin Cycle CO2 Enters the Cycle Energy Input ChloropIast 5-Carbon
Molecules
Regenerated
6-Carbon Sugar
Produced
Sugars and other compounds

20. The Process
Carbon dioxide enters the cycle and uses ATP and NADPH to energize existing molecules.
One molecule leaves the cycle to make glucose.
The rest are recycled to keep the cycle going.
Two turns of the cycle are needed to make one glucose molecule.

22. Photosynthesis: An Overview
Light O2
Sugars
CO2
Chloroplast
Chloroplast
NADP+
ADP + P
Light-
Dependent
Reactions
Calvin
Cycle
ATP
NADPH

23. Factors Affecting Photosynthesis
Shortage of water
Water is needed to donate hydrogens to the light cycle
Temperature
If the temperature falls than the enzymes that allow photosynthesis to occur no longer function
Intensity of light
Plants need the correct wavelength of light to perform photosynthesis
As the intensity changes leaves will change colors to capitalize on the light available