In frog the urinary bladder is

Options

A. (1) Absent
B. (2) Paired
C. (3) Bilobed
D. (4) Trilobed

Answer

### Step-by-Step Solution:

1. **Understanding the Urinary Bladder in Frogs**:
- The urinary bladder in frogs is a specific organ responsible for storing urine before it is excreted.

2. **Characteristics of the Urinary Bladder**:
- The urinary bladder in frogs is described as **thin-walled**. This means that the walls of the bladder are not thick, allowing for flexibility and expansion.
- It is also **bi-lobed**, which indicates that the bladder is divided into two lobes. This is a distinctive feature compared to other animals.

3. **Location of the Urinary Bladder**:
- The urinary bladder is attached to the **ventral side of the cloaca**. The cloaca is a common cavity at the end of the digestive tract that serves as the only opening for the intestinal, reproductive, and urinary tracts.

4. **Distensibility of the Urinary Bladder**:
- The urinary bladder in frogs is described as **distensible**. This means that it can expand significantly when filled with urine. When empty, it becomes smaller and less noticeable (inconspicuous).

5. **Conclusion**:
- Based on these characteristics, we can conclude that the urinary bladder in frogs is a **thin-walled, bi-lobed sac** located on the ventral side of the cloaca and is capable of distension.

### Final Answer:
The urinary bladder in frogs is a **thin-walled, bi-lobed sac attached to the ventral side of the cloaca**.

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