State whether the following statements are true or false.Azotobacter is a heterotrophic nitrogen fixing bacterium.
A. True
B. False

Answer

To determine whether the statement "Azotobacter is a heterotrophic nitrogen-fixing bacterium" is true or false, we can follow these steps:

### Step 1: Understand what Azotobacter is
Azotobacter is a type of bacterium that is known for its ability to fix nitrogen. It is classified as a free-living bacterium, meaning it does not depend on a host organism for survival.

**Hint:** Research the characteristics of Azotobacter to understand its role in the ecosystem.

### Step 2: Determine the nutritional mode of Azotobacter
Azotobacter is classified as a heterotrophic bacterium. This means it obtains its nutrients by consuming organic compounds, rather than producing its own food through photosynthesis.

**Hint:** Look into the definitions of heterotrophic and autotrophic organisms to clarify their differences.

### Step 3: Identify the nitrogen-fixing capability
Azotobacter is known for its ability to fix atmospheric nitrogen into a form that can be utilized by plants. This process is crucial for enhancing soil fertility.

**Hint:** Explore the process of nitrogen fixation and its importance in agriculture and ecology.

### Step 4: Combine the information
Since Azotobacter is both heterotrophic and capable of nitrogen fixation, the statement "Azotobacter is a heterotrophic nitrogen-fixing bacterium" is indeed true.

**Hint:** Summarize the key points about Azotobacter's characteristics to reinforce your understanding.

### Conclusion
The correct answer to the question is:
**A. True**