1. Photosynthesis in Overview
Process by which plants and other autotrophs store the energy of sunlight into sugars.
The energy from the sun is converted into the chemical energy of glucose.
Requires sunlight, water, and carbon dioxide.
Overall equation:
6 CO H20  C6H12O O2
Occurs in the leaves of plants in organelles called chloroplasts.

2. Chloroplast Structure
Inner membrane of the thylakoid is called the thylakoid membrane.
Thickened regions called thylakoids. A stack of thylakoids is called a granum. (Plural – grana)
Stroma is a liquid surrounding the thylakoids.

3. Photosynthesis: The Chemical Process
Occurs in two main phases.
1. ‘Light’ Dependent Reactions.
2. Light Independent Reactions (aka – the Calvin Cycle, Dark reactions).
Light reactions are the “photo” part of photosynthesis. Light is absorbed by pigments.
Dark reactions are the “synthesis” part of photosynthesis. Glucose is produced during this stage.

4. The Reactions of Photosynthesis
THE LIGHT DEPENDENT REACTIONS
THE LIGHT INDEPENDENT REACTIONS
Occurs in the grana (thylakoid)
Occurs in the stroma
AKA: light reactions
AKA: dark reactions, calvin cycle and carbon fixation reactions
Uses light and water
Uses carbon dioxide, ATP, NADPH
Produces oxygen, ATP, NADPH
Produces glucose
Photolysis occurs (photochemical rxns)
Cyclical reactions begin & end with RuBP
Provides atmospheric oxygen
Sugar produced is used for cellular respiration
Requires enzymes
Dependent upon light
Not dependent upon light
ATP and NADPH produced here energize the dark reactions
ATP and NADPH from light reactions energize these dark reactions
Occur in the chloroplast

6. Light Dependent Reactions
Light-dependent reactions occur in the grana.
Light and water are required for this process.
Energy molecules are formed. (ATP and NADPH). These molecules power the dark reactions.
Photolysis occurs. This is the splitting of water molecules.
Oxygen gas is made as a waste product.

7. Light Independent Reactions
Dark reactions (light-independent) occur in the stroma.
ATP and NADPH molecules created during the light reactions power the production of glucose.
Carbon dioxide is “fixed” into Phosphoglyceraldehyde (PGAL).
2 PGAL’s come together to form glucose.

9. Pigments
Chlorophyll A is the most important photosynthetic pigment. Green!
Other pigments accessory pigments are also present in the leaf.
Chlorophyll B (yellow-green)
Carotenoids (yellow-orange).
Xanthophylls (yellow).

10. Chromatography
A technique used to separate the component parts of a mixture according to how well each part dissolves within a solvent.
The more soluble a part is, the farther it will travel up the chromatography paper.
Allows scientists to observe parts of a mixture that they would otherwise be unable to see.

11. Do Now Wash hands. Wash test tube and flask at your desktops.
Put all materials away and tucked under your desk with the exception of a pencil, pen and lab packet.
Lab # 9: Analysis of Plant Pigments

12. Do Now Follow lab steps a through d.
Raise your hand for plant pigment solution.
Complete steps e through h.

13. Do Now Get a pair of goggles. Get solvent from Mrs. Muraco
Follow steps j and k. Be sure to record the time.

14. Do Now Step m. Record the time. Answer questions 3-9.
Complete calculations.
Fill in table.
Answer 1-3.
Label pigments and Rf values and hand in lab.