Photosynthesis: The Light-Dependent Reactions

The video explains the light-dependent reactions of photosynthesis, which occur in chloroplasts. It details the roles of Photosystem II, Cytochrome b6f complex, Photosystem I, and ATP Synthase in converting light energy into chemical energy. The process involves electron transport chains, proton gradients, and the production of oxygen, ATP, and NADPH. These products are essential for the subsequent light-independent reactions that synthesize sugars.

What is the primary role of the light-dependent reactions in photosynthesis?

• To release nitrogen into the air

• To produce glucose directly

• To absorb carbon dioxide

• To capture and store energy from sunlight

Which molecule acts as the primary electron acceptor in Photosystem II?

• Chlorophyll a

• Plastoquinone Qb

• Pheophytin

• Ferredoxin

What is the function of the Cytochrome b6f complex in the light-dependent reactions?

• To split water molecules

• To absorb light energy

• To pump protons across the thylakoid membrane

• To produce glucose

What is produced as a result of water splitting in Photosystem II?

• Glucose

• Carbon dioxide

• NADPH

• Oxygen

What is the role of Photosystem I in the light-dependent reactions?

• To provide an extra boost of light energy to electrons

• To absorb carbon dioxide

• To produce ATP

• To split water molecules

Which enzyme is responsible for forming NADPH in the light-dependent reactions?

• ATP Synthase

• Photosystem II

• Ferredoxin NADP reductase

• Cytochrome b6f

How is ATP produced in the light-dependent reactions of photosynthesis?

• By absorbing sunlight directly

• Using the electrochemical gradient created by hydrogen ions

• Through the Calvin cycle

• By splitting water molecules