Light reaction

The video explains photosynthesis, focusing on light-dependent and light-independent reactions. It details the role of chlorophyll in absorbing light, the function of photosystems, and the electron transport chain. The process of ATP and NADPH production is covered, including the Z scheme and cyclic photophosphorylation. The chemiosmotic hypothesis and ATP synthesis via ATP synthase are also discussed.

What are the two main phases of photosynthesis?

• Light-dependent and light-independent reactions

• Photosynthetic and non-photosynthetic reactions

• Oxidative and reductive reactions

• Anabolic and catabolic reactions

Where do the light-dependent reactions of photosynthesis occur?

• In the mitochondria

• In the thylakoid membranes

• In the cytoplasm

• In the stroma

What is the primary role of chlorophyll in photosynthesis?

• To absorb light energy

• To transport electrons

• To release oxygen

• To synthesize glucose

What is the maximum absorption wavelength of the special pair of chlorophyll molecules in PSI?

• 680 nanometers

• 700 nanometers

• 720 nanometers

• 650 nanometers

What is the role of the electron transport chain in photosynthesis?

• To release oxygen

• To synthesize glucose

• To generate a proton gradient

• To absorb light energy

What is the Z scheme in photosynthesis?

• A representation of electron flow from PSII to PSI

• A diagram of chlorophyll structure

• A pathway for glucose synthesis

• A model for cyclic electron flow

Under what conditions does cyclic photophosphorylation occur?

• When chlorophyll is absent

• When light is below 680 nm

• When only PSI is activated

• When both PSI and PSII are activated

Who proposed the chemiosmotic hypothesis?

• Peter Mitchell

• Rosalind Franklin

• James Watson

• Albert Einstein

What is the function of the ATP synthase complex?

• To absorb light

• To synthesize ATP

• To transport electrons

• To split water molecules

How many protons are required to produce one molecule of ATP?

• Two

• Three

• Four

• Five