Z-scheme

Definition

A Z-scheme is a diagrammatic representation of the electron transport chain in photosynthesis. It illustrates the flow of electrons through photosystem II and photosystem I, highlighting energy changes.

5 Must Know Facts For Your Next Test

1. The Z-scheme shows the movement of electrons from water to NADP+ during light-dependent reactions.
2. Photosystem II absorbs light at 680 nm, while Photosystem I absorbs light at 700 nm.
3. The Z-scheme gets its name due to its characteristic 'Z' shape formed by the energy levels of electrons.
4. ATP and NADPH are produced as a result of the electron flow represented in the Z-scheme.
5. Photolysis of water occurs at Photosystem II, releasing oxygen as a byproduct.

Review Questions

• What are the primary components involved in the Z-scheme?
• How does the absorption wavelength differ between Photosystem II and Photosystem I?
• What are the end products of the electron flow in the Z-scheme?

Related terms

Photosystem II:

A protein complex that uses light energy to drive water photolysis and generate high-energy electrons.

Photosystem I:

A protein complex that uses light energy to produce NADPH from NADP+.

Electron Transport Chain:

A series of protein complexes that transfer electrons via redox reactions to form a gradient used for ATP synthesis.