Putrefying bacteria act upon

Options

A. Fats
B. Carbohydrates
C. Proteins
D. Starch.

Answer

**Step-by-Step Solution:**

1. **Understanding Putrefying Bacteria**: Putrefying bacteria are a type of decomposer that break down organic matter. They play a crucial role in the decomposition process, particularly in breaking down dead organisms and waste products.

2. **Focus on Proteins**: Among the options given (fats, carbohydrates, proteins, and starch), putrefying bacteria primarily act upon proteins. This is because proteins are complex molecules that require decomposition into simpler compounds.

3. **Decomposition Process**: When putrefying bacteria act on proteins, they break them down into amino acids. These amino acids can then be further decomposed or utilized by the bacteria for energy.

4. **Formation of Ammonium Ions**: As the proteins are decomposed into amino acids, the bacteria convert these amino acids into ammonium ions. This process is essential for nutrient cycling in ecosystems.

5. **Nitrification**: The ammonium ions produced can then be converted by nitrifying bacteria into nitrates, which are essential nutrients for plants. This illustrates the interconnectedness of different types of bacteria in nutrient cycling.

6. **Conclusion**: Therefore, the correct answer to the question is that putrefying bacteria act upon proteins.

**Final Answer**: Putrefying bacteria act upon proteins.

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