Chemical used most by plant is

Options

A. Carbon dixode
B. Oxygen
C. Cytochrome
D. Nitrogen.

Answer

To answer the question "Chemical used most by plant is", we can follow these steps:

### Step 1: Identify the Options
The options given are:
1. Carbon Dioxide
2. Oxygen
3. Cytochrome
4. Nitrogen

### Step 2: Analyze Each Option
- **Carbon Dioxide**: Plants absorb carbon dioxide from the atmosphere. It is a crucial component in the process of photosynthesis, where plants convert carbon dioxide and water into glucose and oxygen.

- **Oxygen**: While essential for plant respiration, oxygen is primarily a by-product of photosynthesis. Plants do not use oxygen as a primary input for their growth or food production.

- **Cytochrome**: This refers to a group of proteins involved in electron transport within mitochondria and chloroplasts. While important for cellular respiration and photosynthesis, cytochromes are not a chemical that plants use in large quantities.

- **Nitrogen**: This is an essential macronutrient for plants, necessary for the synthesis of amino acids and proteins. However, it is not used in the same way as carbon dioxide in the process of photosynthesis.

### Step 3: Conclusion
After analyzing the options, it is clear that the chemical used most by plants is **Carbon Dioxide**. This is because it is the primary raw material for photosynthesis, which is the process by which plants produce their food.

### Final Answer
The chemical used most by plants is **Carbon Dioxide**.

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