Which one of the following is not a characteristic feature of frog

Options

A. The skin is moist and slimy
B. Each of the fore limbs and hind limbs end in five digits
C. Hepatic portal and renal portal systems are present
D. Skin, buccal cavity and lungs are respiratory organs

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
- The question asks for a characteristic feature that is NOT associated with frogs. We need to analyze each option to determine which one does not apply to frogs.

2. **Analyzing Option A: "The skin is moist and slimy."**
- Frogs are known for their moist and slimy skin, which helps in respiration and keeps them hydrated. This is a characteristic feature of frogs.

3. **Analyzing Option B: "Each of the forelimbs and hind limbs has five digits."**
- Frogs have four limbs: the forelimbs typically have four digits, while the hind limbs have five digits. Therefore, this statement is incorrect regarding the forelimbs.

4. **Analyzing Option C: "Hepatic portal and renal portal system are present."**
- Frogs possess both hepatic and renal portal systems. The hepatic portal system carries blood from the digestive organs to the liver, while the renal portal system carries blood from the posterior body to the kidneys. This statement is correct.

5. **Analyzing Option D: "Skin, buccal cavity, and lungs are respiratory organs."**
- Frogs use their skin, buccal cavity, and lungs for respiration. This is a true statement about frogs.

6. **Conclusion:**
- After analyzing all options, we find that Option B is the only statement that is not a characteristic feature of frogs. Frogs do not have five digits on both forelimbs and hind limbs; they have four digits on forelimbs and five on hind limbs.

**Final Answer:**
- The option that is NOT a characteristic feature of frogs is **Option B: Each of the forelimbs and hind limbs has five digits.**

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