Which of the following is the primary pigment involved in capturing light energy during photosynthesis in plants?

• A. Xanthophyll
• B. Chlorophyll a
• C. Chlorophyll c
• D. Carotene

Answer: (B)

Verified step by step guidance

1. Understand the role of pigments in photosynthesis: Pigments are molecules that absorb specific wavelengths of light. In plants, these pigments are located in the chloroplasts and are essential for capturing light energy to drive the process of photosynthesis.
2. Identify the primary pigment: While plants have several pigments (e.g., chlorophylls, carotenoids), the primary pigment responsible for capturing light energy is chlorophyll a. This pigment absorbs light most efficiently in the blue-violet and red regions of the spectrum.
3. Differentiate between chlorophyll a and other pigments: Chlorophyll a is the main pigment directly involved in the light reactions of photosynthesis. Other pigments, such as chlorophyll b, carotenoids (e.g., carotene), and xanthophylls, act as accessory pigments. They broaden the range of light absorption and transfer energy to chlorophyll a.
4. Understand why chlorophyll a is the correct answer: Chlorophyll a is essential for the conversion of light energy into chemical energy during the light-dependent reactions of photosynthesis. It is the only pigment that directly participates in the photochemical reactions.
5. Review the incorrect options: Xanthophyll and carotene are accessory pigments that protect the plant from excess light and assist in light absorption but are not the primary pigments. Chlorophyll c is found in some algae, not in higher plants, and is not the primary pigment in photosynthesis.