Final answer:
The primary job of photosystems is to harvest light in the process of photosynthesis.
Step-by-step explanation:
The primary job of photosystems is to harvest light. Photosystems are protein complexes found in the thylakoid membrane of chloroplasts. They contain pigments such as chlorophyll that are able to absorb light energy. This energy is then used in the process of photosynthesis to convert light energy into chemical energy.
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