Photosynthesis- Light Reactions

What is photosynthesis?

An endergonic process that uses CO2, H2O, and sunlight to make glucose and O2

What are the two main parts of photosynthesis?

Light-harversting reactions and the Calvin Cycle

What is the function of the light-harvesting reactions?

Use sunlight to energize electrons, produce ATP and NADPH, and split water to make O2

What is the function of the Calvin Cycle?

Uses ATP and NADPH to convert CO2 into glucose

What is the ultimate energy source for photosynthesis?

The Sun

What organ and organelle perform photosynthesis?

Leaves; chloroplasts

Which wavelengths are reflected by chloroplasts?

Green/yellow

What is the ultimate source of electrons in photosynthesis?

Water (H2O)

Which process in photosynthesis produce ATP?

Cyclic and non-cyclic photophosphorylation

Which process consumes ATP?

The Calvin Cycle?

Which process consumes CO2?

The Calvin Cycle

Which process produces O2?

Non-cyclic photophosphorylation

What chemical is the raw material for plant growth?

CO2

How is ATP generated in the light reactions?

Electron flow pumps H into the thylakoid space; ATP synthase uses the gradient to make ATP

What does non-cyclic photophosphorylation use and produce?

Uses PSII & PSI; produces ATP, NADPH, and O2

What does cyclic photophosphorylation use and produce?

Uses PSI only; produces ATP only

What are photosynthetic pigments?

Molecules that absorb visible light and transfer energy to the reaction center

What are antenna complexes?

groups of pigments that capture light energy and funnel it to the reaction center

What does an absorption spectrum show?

The wavelengths each pigment absorbs

What does an action spectrum show?

The rate of photosynthesis at each wavelength

Which wavelengths of light are absorbed by cholorplasts?

violet/blue and orange/red