Photosynthesis

• The law of conservation of mass, also known as the principle of mass/matter conservation, states that the mass of an isolated system (closed to all matter and energy) will remain constant over time. 

• The law of conservation of energy: energy cannot be created or destroyed, but it can be changed from one form to another.

Photosynthesis

• Photosynthesis transforms solar energy into carbohydrates. • Essential for the continuance of life• The source of food and oxygen for nearly all living things

6CO2 + 6H2O C6 H12O6 + 6O2

solar energy

Photosynthesis

• Raw materials: CO2 + H2O

• End products: carbohydrates

• Organelle: chloroplast

• Two sets of reactions

—Light-dependent reaction O2 is produced

—Calvin cycle reaction carbohydrate is produced

Light-dependent reaction• An energy capturing reaction

• Visible light has many components

Pigments in chloroplast absorb various portions of visible light

Chlorophyll a & b:

violet, blue, and red

Carotenoid:

violet, blue, and green

Solar energy photosystem II (pigments)

breaking down H2O Electrons (from H2O)

electron transport chain (ETC) photosystem I NADP + NADPH

Calvin cycle reaction

• Using ATP & NADPH made in the light reactions to produce

carbohydrate

• taking place in the stroma

Paper Chromatography• An analytical chemistry

technique: separating & identifying mixtures that are / can be colored

• A piece of paper is dipped into solvent

• solvent molecules: keep finding new places to stick to; climb up the paper being replaced by new solvent molecules below

• molecules dissolved in the solvent: are carried along up the paper

sample mixture

solvent level

solvent levelsample mixture

solvent level

• different compounds in the sample mixture travel at different rates

• differences in solubility in the solvent & in their attraction to the paper fibers

• the more soluble the component the further it goes

Experiments

• Following handout