Nitrosomonas is a

Options

A. chemolithotroph
B. chemoheterotroph
C. autotroph
D. heterotroph

Answer

To determine what type of organism Nitrosomonas is, we can follow these steps:

### Step 1: Identify Nitrosomonas
Nitrosomonas is a type of bacteria, specifically known as a nitrifying bacterium.

### Step 2: Understand its Role
Nitrosomonas plays a crucial role in the nitrogen cycle by converting ammonium salts (NH4+) into nitrites (NO2-). This process is essential for nitrogen fixation in the soil.

### Step 3: Classify Nitrosomonas
To classify Nitrosomonas, we need to understand the types of nutritional modes in bacteria:
- **Chemolithotrophs**: Organisms that obtain energy by oxidizing inorganic substances.
- **Chemoheterotrophs**: Organisms that obtain energy by consuming organic compounds.
- **Autotrophs**: Organisms that produce their own food. This can be further divided into:
- **Photoautotrophs**: Use light energy to produce food.
- **Chemoautotrophs**: Use chemical reactions to produce food.

### Step 4: Determine the Correct Classification
Since Nitrosomonas does not rely on light for energy but instead uses chemical processes to convert ammonium to nitrites, it falls under the category of **chemoautotrophs**.

### Conclusion
Thus, Nitrosomonas is classified as a **chemoautotroph**.

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