Question

Mention two compatible differences between PS-I and PS-II.

Answer 1

The main difference between the two is the wavelengths of light to which they respond. Photosystem I absorbs light with wavelengths shorter than 700 nm, whereas photosystem II absorbs light with wavelengths shorter than 680 nm. However, they are both equally important in the process of oxygenic photosynthesis. Photosystem I (PSI, or plastocyanin-ferredoxin oxidoreductase) is the second photosystem in the photosynthetic light reactions of algae, plants, and some bacteria. Photosystem I is an integral membrane protein complex that uses light energy to produce the high energy carriers ATP and NADPH. When photosystem II absorbs light, electrons in the reaction-centre chlorophyll are excited to a higher energy level and are trapped by the primary electron acceptors.