3.5 I Can Statements

What processes allow organisms to capture and store energy during photosynthesis?

Photosynthetic processes involving light-dependent and light-independent reactions.

Where did the evolution of photosynthesis occur?

Photosynthesis evolved primarily in cyanobacteria.

What evidence supports the contribution of cyanobacteria to atmospheric oxygenation?

Cyanobacteria's photosynthetic activity produced oxygen as a byproduct, contributing to the oxygenation of the atmosphere.

What are the light-dependent reactions?

Reactions that convert light energy into chemical energy in the form of ATP and NADPH.

How is ATP synthesized in light-dependent reactions?

ATP is synthesized through photophosphorylation using ATP synthase as protons flow back across the thylakoid membrane.

How is NADPH synthesized in light-dependent reactions?

NADPH is produced by the transfer of electrons from water to NADP+ via the electron transport chain.

How do cells capture energy from light?

Cells capture energy from light through pigments like chlorophyll that absorb light.

How do cells transfer energy from light to biological molecules?

Energy is transferred through electron excitation and subsequent chemical reactions in photosystems.

What is chlorophyll?

Chlorophyll is a green pigment in plants that absorbs light for photosynthesis.

What is the effect on electrons after absorbing energy from light?

Electrons are elevated to a higher energy state, becoming excited.

What is the anatomy of the thylakoid membrane?

The thylakoid membrane contains photosystems, electron transport chains, and ATP synthase.

What is a photosystem?

A photosystem is a complex of proteins and pigments that captures light energy.

What is the relationship between the photosystems and the electron transport chain?

Photosystems generate high-energy electrons that are transferred to the electron transport chain.

How is the proton gradient produced in the electron transport chain?

The proton gradient is produced by the pumping of protons into the thylakoid lumen during electron transport.

What is the relationship between the proton gradient and ATP synthesis?

The proton gradient drives ATP synthesis through ATP synthase as protons flow back into the stroma.

What is the relationship between light reactions and the Calvin cycle?

The light reactions produce ATP and NADPH, which are used in the Calvin cycle to convert carbon dioxide into glucose.