Green plants utilize chlorophyll a and chlorophyll b to absorb light energy in photosynthesis. Which of the following best describes the role of these pigments?

• A. They act as enzymes that catalyze the splitting of water.
• B. They absorb light energy and transfer it to the photosynthetic reaction center.
• C. They store glucose produced during photosynthesis.
• D. They transport electrons directly to NADP\(^+\).

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the role of chlorophyll a and chlorophyll b in photosynthesis. These pigments are specialized molecules that absorb light energy, which is essential for driving the photosynthetic process.
2. Step 2: Recall that chlorophyll a and chlorophyll b are not enzymes. Enzymes catalyze chemical reactions, such as the splitting of water (a process performed by the oxygen-evolving complex, not chlorophyll). Therefore, the option stating they act as enzymes is incorrect.
3. Step 3: Recognize that chlorophyll pigments do not store glucose. Glucose is a product of the Calvin cycle, which occurs after the light-dependent reactions. Thus, the option about storing glucose is also incorrect.
4. Step 4: Understand that chlorophyll pigments do not directly transport electrons to NADP\(^+\). Instead, they transfer the absorbed light energy to the photosynthetic reaction center, where it is used to excite electrons. These excited electrons are then passed through the electron transport chain, eventually reducing NADP\(^+\) to NADPH.
5. Step 5: Conclude that the correct description of the role of chlorophyll a and chlorophyll b is that they absorb light energy and transfer it to the photosynthetic reaction center, enabling the light-dependent reactions of photosynthesis to proceed.