Find out the wrong statement

Options

A. Amnion is outer layer containing amniotic fluid that acts as shock absorber to soft embryo
B. Yolk sac is a foetal membrane that helps in nourishment of the embryo
C. In mammals, allantois is not excretory in function
D. Chorio-allantoic membrane develops villi and participates in development of placenta

Answer

To solve the question of finding the wrong statement among the provided options regarding extra embryonic membranes, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: We need to identify which of the given statements about extra embryonic membranes is incorrect.

2. **Analyze Each Statement**:
- **Option A**: "Amnion is outer layer containing amniotic fluid that acts as a shock absorber to the soft embryo."
- **Analysis**: This statement is true. The amnion is indeed the outer layer and contains amniotic fluid, which serves as a shock absorber for the embryo.

- **Option B**: "Yolk sac is a fetal membrane that helps in nourishment of the embryo."
- **Analysis**: This statement is also true. The yolk sac provides nourishment to the embryo, especially in early development.

- **Option C**: "In mammals, allantois is not excretory in function."
- **Analysis**: This statement is false. The allantois does have an excretory function as it helps in the removal of waste products from the embryo.

- **Option D**: "Chorioallantoic membrane develops villi and participates in the development of placenta."
- **Analysis**: This statement is true. The chorioallantoic membrane does develop villi and is involved in the formation of the placenta.

3. **Identify the Wrong Statement**: Based on the analysis, Option C is the wrong statement because it incorrectly states that the allantois is not excretory in function.

4. **Conclusion**: The answer to the question is Option C.

### Final Answer:
The wrong statement is **Option C**: "In mammals, allantois is not excretory in function."

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