1. PHOTOSYNTHESIS

2. Photosynthesis carbon dioxide + water + energy glucose + oxygen
photosynthesis- the process of using light energy from the sun to convert carbon dioxide and water into glucose or carbohydrates
chemical formula:
6 CO2 + 6 H2O + energy  C6H12O6 + 6 O2
carbon dioxide + water + energy glucose + oxygen

3. Autotrophs performed by autotrophs or plants
autotrophs- organisms that are capable of making their own food, glucose

4. Conditions Necessary For Photosynthesis
sunlight- only the red and blue wavelengths of white light are involved in photosynthesis
chlorophyll- a green pigment in plants that traps energy from the sun
water- supplies the hydrogen atoms (ions) needed to make glucose
carbon dioxide- supplies the carbon and oxygen atoms needed to make glucose

5. Photosynthesis
All organisms use energy to carry out functions for life.
All energy is obtained directly or indirectly from the sun.
Some organisms can trap energy from light and store it within organic compounds called photosynthesis.

6. Importance of Photosynthesis
provides food for plants and animals in the form of carbohydrates or sugar or glucose
uses oxygen as a waste product which is released into the atmosphere
changes the energy from the sun into a usable form for living organisms
provides the structural components in the cell walls of plants which is cellulose

7. Chloroplasts photosynthesis takes place inside the chloroplast
chloroplast has a double membrane with the inner membrane having many folds
the folds of the inner membrane fuse to together to form thylakoids
thylakoids- disk-shaped structures that contain chlorophyll; resemble coins

8. Chloroplast- continued
neatly stacked thylakoids are called grana
a gel-like solution surrounds the grana and completely fills the inner membrane called the stroma
Chlorophyll a absorbs more red light and less blue light than Chlorophyll b
only Chlorophyll a is directly involved in the light reactions of photosynthesis

9. Process of Photosynthesis
Stage 1- Light Dependent Reactions
Stage 2 – Light Energy Converted to Chemical Energy
Stage 3 – Calvin Cycle

10. Stage 1: Light Dependent Reaction
takes place inside the thylakoids
energy is captured by chlorophyll from sun light
water is split into hydrogen ions, oxygen ions, and electrons
hydrogen ions are used to make glucose
energy released from electrons are used to make ATP molecules which are high energy molecules
oxygen is released from the chloroplast into the atmosphere
energy is also stored in NADP+ which is an electron acceptor; once joined with an electron it becomes NADPH

11. Stage 2: Conversion of Energy
light energy is converted to chemical energy
energy is stored in the form of ATP and NADPH molecules
ATP- high energy molecules
NADPH- electron acceptors

12. Stage 3: Calvin Cycle occurs inside the stroma
carbon dioxide and hydrogen combine to form glucose
energy stored in ATP and NADPH are used to form glucose

13. Stage 1: Light Dependent Reaction
requires sunlight and takes place in the thylakoids
the energy absorbed by the electrons of Chlorophyll a (photosynthesis II or I) causes these electrons to enter a higher energy level or “energized”
energized electrons leave Chlorophyll a (photosystem II) which makes Chlorophyll a oxidized and must undergo reduction to add back electrons

14. Stage 1: Light Dependent Reaction
energized electrons combine with molecules called the primary electron acceptors
primary electron acceptors- capture these loose electrons
primary electron acceptors guide the electrons to the electron transport chain
electron transport chain- transfers the high energy electrons from one molecule to the next in the series
this energy is used to make ATP molecules

15. Stage 1: Light Dependent Reaction
an enzyme inside the thylakoid splits a water molecule into hydrogen ions (H+ or protons), oxygen gas, and electrons
electrons released when the water molecule splits in the thylakoid replaces the electrons lost from the Chlorophyll a in photosystem II combine with Chlorophyll a in photosystem I
electrons in both photosystems must be replenished in order for photosynthesis to occur
oxygen is released into the atmosphere

16. Stage 2: Energy Conversion First Path
ATP molecules are made by joining a phosphate group to ADP or two phosphate groups to AMP
ATP or adenosine triphosphate- a high energy compound that supplies energy for all chemical reactions within a living organism
ADP or adenosine diphosphate- results when ATP loses a phosphate group to release energy
AMP or adenosine monophosphate- results when ADP loses a phosphate group to provide energy

17. Stage 2: Energy Conversion
electrons + ADP + 1 phosphate group = ATP
electrons + AMP + 2 phosphate groups = ATP

18. Stage 2: Energy Conversion Second Path
energized electros in Chlorophyll a (photosystem I) are accepted by the primary electron acceptors
again these electron acceptors direct the energized electrons to a different electron chain transport
electrons combine with a hydrogen ion and NADP+ to form NADPH

19. Stage 2: Energy Conversion Second Path
NADP+ - an organic compound that accepts electrons
NADPH- an energy storing compound that will be used in the Calvin Cycle
hydrogen is bonded to NADPH to be used in making glucose in Calvin Cycle

20. Stage 3: Calvin Cycle (Dark Reaction)
energy is supplied by ATP and NADPH which were made in the light reaction
simple inorganic compounds of carbon dioxide are used to make a complex organic compound called glucose or carbohydrates
carbon fixation- carbon atoms from carbon dioxide are bonded into organic compounds
takes place in the stroma of the chloroplasts
carbon dioxide combines with a five-carbon compound called RuBP(ribulose bisphosphate) to form a six-carbon compound

21. Stage 3: Calvin Cycle
carbon dioxide joins with RuBP to form a six-carbon compound that splits into 2 three-carbon compounds called PGA (phosphoglyceric acid or 3-phosphoglycerate)
PGA is converted into another three-carbon compound called PGAL (phosphoglyceraldehyde)
PGA + phosphate group + hydrogen = PGAL
(ATP) (NADPH)

22. Stage 3: Calvin Cycle
products of the Calvin Cycle are PGAL, phosphate group, ADP, and NADP+
most PGAL is changed back into RuBP
some PGAL is converted into amino acids, lipids, and carbohydrates

23. Rate of Photosynthesis
light intensity- increase light intensity, increases photosynthesis for a limited time, then levels off
carbon dioxide- increase carbon dioxide, increases photosynthesis for a limited time, then levels off
temperature- increase temperature, increases photosynthesis
chlorophyll- increase the amount of chlorophyll, increase photosynthesis

24. END
Note Quiz

25. Note Quiz What are the products of the Calvin Cycle?
What are the two wavelengths of light that are used in photosynthesis?
What is the role of chlorophyll in photosynthesis?
What is the compound that carbon dioxide will combine in the Calvin Cycle?
What are the products of the Light Dependent Reaction?

26. 6. What does water supply in the process of photosynthesis?
7. What are the energy sources used in the Calvin Cycle or Dark Reaction?
8. What is PGAL?
9. How is PGA formed?
10. What does carbon dioxide contribute to photosynthesis?