Water requirement of Kangaroo/Desert Rat is largely met by

Options

A. Hydration of food
B. Metabolic water
C. Hygroscopic skin
D. Moist soil.

Answer

To answer the question about how the water requirement of the kangaroo or desert rat is largely met, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Organism**: The question refers to the kangaroo rat, which is also known as the desert rat. This animal is well-adapted to survive in arid desert environments.

2. **Understand Their Diet**: Kangaroo rats primarily consume seeds, particularly grass seeds. They may also eat small insects occasionally.

3. **Water Sources**: The water requirement for kangaroo rats is met through the food they consume. Specifically, they can extract a significant amount of water from the seeds they eat.

4. **Metabolic Water**: When kangaroo rats metabolize the seeds, they produce metabolic water as a byproduct. This means that the water is generated internally through the process of digestion and metabolism of food.

5. **Kidney Adaptations**: Kangaroo rats have highly adapted kidneys that allow them to concentrate their urine. This adaptation helps them retain as much water as possible, minimizing water loss.

6. **Evaluate Options**:
- **Hydration of Food**: This option suggests that water is absorbed from food, which is partially true but not the primary source.
- **Metabolic Water**: This is the correct answer, as it refers to the water produced from the metabolic processes of the seeds they consume.
- **Hygroscopic Skin**: This is incorrect because their skin does not absorb water from the environment.
- **Moist Soil**: This is also incorrect as they live in a desert where moist soil is not available.

7. **Conclusion**: The water requirement of the kangaroo or desert rat is largely met by **metabolic water** produced from the oxidation of the seeds they consume.

### Final Answer:
The water requirement of the kangaroo or desert rat is largely met by **metabolic water**.

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