Birds do not possess

Options

A. Teeth
B. Urinary Bladder
C. Gall Bladder
D. All the above

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks what birds do not possess among the given options: teeth, urinary bladder, gallbladder, or all of the above.

2. **Analyzing the First Option - Teeth**:
- Birds do not have teeth. Instead of chewing food with teeth, they use a muscular part of their stomach called the gizzard to grind food.
- This adaptation is important for their feeding habits.

3. **Analyzing the Second Option - Urinary Bladder**:
- Birds lack a urinary bladder. In birds, nitrogenous wastes are excreted in the form of uric acid, which is less toxic and conserves water.
- The absence of a urinary bladder helps reduce body weight, which is beneficial for flight.

4. **Analyzing the Third Option - Gallbladder**:
- Many birds do not possess a gallbladder. The gallbladder is responsible for storing bile, which aids in fat digestion.
- Some species of birds can produce bile directly from the liver as needed, eliminating the need for a gallbladder.

5. **Conclusion**:
- Since birds do not possess teeth, a urinary bladder, or a gallbladder, the correct answer is "all the above".

**Final Answer**: All the above (birds do not possess teeth, urinary bladder, and gallbladder).

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