In oxygenic photosynthesis, which pigment acts as the primary photochemical catalyst in the reaction center by converting light energy into chemical energy through charge separation?

• A. Phycoerythrin
• B. Chlorophyll a
• C. Chlorophyll b
• D. Carotenoids

Answer: (B)

Verified step by step guidance

1. Understand that in oxygenic photosynthesis, light energy is captured by pigments and converted into chemical energy in the reaction center of the photosystem.
2. Identify the role of different pigments: Phycoerythrin and carotenoids mainly serve as accessory pigments that capture light and transfer energy, while chlorophyll b also acts as an accessory pigment.
3. Recognize that the primary photochemical catalyst in the reaction center is the pigment responsible for charge separation, initiating the conversion of light energy into chemical energy.
4. Recall that chlorophyll a is the pigment located in the reaction center of both Photosystem I and Photosystem II, where it directly participates in the photochemical reactions.
5. Conclude that chlorophyll a acts as the primary pigment converting light energy into chemical energy through charge separation in oxygenic photosynthesis.