November 13, 2012O Write out the overall reaction of

photosynthesis

Announcements

Review of PhotosynthesisO At your tables pull out your notes and

come up with answers to these questions.

O What is Photosynthesis?

O Where does the mass of a plant come from as it grows?

O What are the reactants of Photosynthesis (what goes in)? What are the products (what comes out)?

How does photosynthesis really work?

O Plants capture sunlight using light absorbing molecules called pigments.

O Chlorophyll: is found in chloroplast, is the principal pigment for capturing sunlight.

ChlorophyllO There are two types of

chlorophyll (A and B) and each captures different wave lengths of UV light.

Photosynthesis can be broken up into three

steps1. Light dependent reactions2. Electron Transport Chain3. Light independent reactions (Calvin

Cycle)

The anatomy of a ChloroplastsO Thylakoids are saclike membranes

which contain the chlorophyll. These are arranged in stacks called grana.

O This is where the light-dependent reactions occur.

Chloroplast anatomy O The stroma is the region outside the

thylakoid membranes. This is where the light-independent reactions take place.

Light-Dependent Reactions

O Light-dependent reactions require light to function, and produce three major products.O OxygenO ATPO NADPH

Products of the Light-dependent reactions

O These products are used to conduct the processes in the light-independent reactions.

Light-dependent

ATPO ATP is a unit of cellular energy

responsible for transferring energy within the cell for metabolism

NADPHO This is an electron carrier used to

transfer energy.

Electron Transport Chain

OElectron transport chains are the cellular mechanisms used for taking energy from sunlight.

OThis requires electron Carriers like NADPH

Light-independent Reactions

O Light-independent reactions take place in the stroma, outside of the thylakoid membrane

O The Calvin Cycle uses ATP NADPH from the previous reactions to produce high-energy sugars.

Calvin CycleO Begins with six CO2 molecules and

ATP to create a six carbon sugar (C6H12O6).

Calvin Cycle