Bacteria which break down the dead organisms of the soil into nitrogen compounds are termed

Options

A. denitrifying bacteria
B. nitrifying and ammonifying bacteria
C. nitrogen fixing bacteria
D. parasitic bacteria.

Answer

To answer the question, "Bacteria which break down the dead organisms of the soil into nitrogen compounds are termed," we will analyze the options provided and identify the correct type of bacteria based on their functions.

**Step-by-Step Solution:**

1. **Understanding the Question:**
- The question asks for bacteria that decompose dead organisms and convert them into nitrogen compounds.

2. **Analyzing the Options:**
- **Denitrifying Bacteria:** These bacteria convert nitrites and nitrates into atmospheric nitrogen (N2). They do not break down dead organisms; instead, they release nitrogen gas into the atmosphere. Therefore, this option is incorrect.

- **Nitrifying and Ammonifying Bacteria:**
- **Nitrifying Bacteria:** These bacteria convert ammonia into nitrites and then into nitrates.
- **Ammonifying Bacteria:** These bacteria break down organic matter (including dead organisms) and convert it into ammonia. This process is known as ammonification. Thus, this option is relevant as it involves the breakdown of dead organisms into nitrogen compounds.

- **Nitrogen-Fixing Bacteria:** These bacteria convert atmospheric nitrogen (N2) into forms that plants can absorb, such as nitrites and nitrates. They do not decompose dead organisms, so this option is incorrect.

- **Parasitic Bacteria:** These bacteria derive nutrients from a host organism and do not play a role in nitrogen cycling or decomposition of dead matter. Therefore, this option is also incorrect.

3. **Conclusion:**
- Based on the analysis, the bacteria that break down dead organisms into nitrogen compounds are the **Nitrifying and Ammonifying Bacteria**. Therefore, the correct answer is option 2.

**Final Answer:**
The bacteria which break down the dead organisms of the soil into nitrogen compounds are termed **Nitrifying and Ammonifying Bacteria**.

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