Besides water, light and a few nutrients, what do algae need in order to grow?

Options

A. Carbon dioxide
B. Methane
C. Uranium
D. Ozone

Answer

To answer the question, "Besides water, light, and a few nutrients, what do algae need in order to grow?" we can break down the requirements for algal growth step by step:

### Step-by-Step Solution:

1. **Identify Basic Requirements**: Algae require water, light, and nutrients to grow. These are the fundamental elements for their survival and growth.

2. **Recognize the Role of Carbon Dioxide**: In addition to the basic requirements, algae need carbon dioxide (CO2). This is crucial because CO2 is used during photosynthesis, which is the process through which algae produce their food.

3. **Understand Photosynthesis**: During photosynthesis, algae utilize light energy to convert carbon dioxide and water into glucose (a simple sugar) and oxygen. The chemical equation for this process can be summarized as:
\[ 6CO_2 + 6H_2O \xrightarrow{\text{light}} C_6H_{12}O_6 + 6O_2 \]
This shows that carbon dioxide and water are transformed into glucose and oxygen, highlighting the importance of CO2 in algal growth.

4. **Chlorophyll's Role**: Algae contain chlorophyll, particularly chlorophyll A, which is essential for capturing light energy needed for photosynthesis. Other pigments like carotenoids also play a role in this process.

5. **Conclusion**: Therefore, besides water, light, and a few nutrients, algae primarily need carbon dioxide to grow effectively.

### Final Answer:
Algae need carbon dioxide in addition to water, light, and a few nutrients to grow.

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