Some bacteria, such as ________, present in the roots of leguminous plants such as peas and peans, also help convert atmospheric nitrogen into ammonium. These fixations are known as ________.

Options

A. Rhizobium, biological nitrogen fixations
B. Protozoa, Nitrification
C. Acetobacter, Ammonification
D. Algae, Denitrification

Answer

**Step-by-Step Solution:**

1. **Identify the Bacteria:** The question asks for a specific type of bacteria that is present in the roots of leguminous plants such as peas and beans. The correct answer is "Rhizobium." These bacteria form a symbiotic relationship with leguminous plants.

2. **Understand the Process:** The next part of the question refers to the process by which these bacteria convert atmospheric nitrogen into ammonium. This process is known as "Biological Nitrogen Fixation."

3. **Summarize the Answers:**
- The bacteria present in the roots of leguminous plants such as peas and beans is **Rhizobium**.
- The process of converting atmospheric nitrogen into ammonium is called **Biological Nitrogen Fixation**.

**Final Answer:**
Some bacteria, such as **Rhizobium**, present in the roots of leguminous plants such as peas and beans, also help convert atmospheric nitrogen into ammonium. These fixations are known as **Biological Nitrogen Fixation**.

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