Light Dependent reactions Q/A

Where are the light dependent reactions located?

Along the thylakoid membrane in chloroplasts.

What breaks down at Photosystems II and what does it release?

Water breaks down, releasing oxygen and hydrogen ions.

What is the oxygen you see here a byproduct of?

It is a byproduct of what you breathe in.

What role does water play in Photosystems II?

Water donates electrons.

What do pigments within Photosystems II do?

They absorb light and transfer that energy to electrons.

What happens to the high energy electrons after the light absorption?

They move through the electron transport chain.

What are the Electron Transport Chains (ETC) responsible for?

They use the energy in the electron to push hydrogen ions from the stroma into the lumen.

What happens to electrons at Photosystems I?

The electrons are reenergized by more light.

Why do the high energy electrons reduce NADP?

To form NADPH, which is essential for subsequent light-independent reactions.

What is NADPH also known as?

Our first product.

What does the formation of NADPH create?

A high concentration of ions in the lumen and a low concentration in the stroma.

How do hydrogen ions move according to the concentration gradient?

They move from high concentration in the lumen to low concentration in the stroma.

How does ATP Synthase produce ATP?

By bonding a phosphate group to ADP, utilizing the energy from the flow of hydrogen ions.

What is the process where the flow of hydrogen ions through ATP synthase drives the conversion of ADP into ATP known as?

Chemiosmosis.

What is the second product

ATP