The portion of the solar spectrum that opens stomata, independent of `CO_2` concentrations, is ………………………. light.

Explanation

To answer the question regarding the portion of the solar spectrum that opens stomata independent of carbon dioxide concentrations, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Stomata**: Stomata are small openings on the surfaces of leaves that facilitate gas exchange and transpiration in plants. They play a crucial role in the plant's ability to take in carbon dioxide and release oxygen.

2. **Role of Light in Stomatal Opening**: The opening of stomata is influenced by various environmental factors, including light. Light triggers the stomata to open, allowing for gas exchange.

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