Complete the following paragraph by selecting the correct options for the blanks A , B ,and C
......A.....is the structural and functional unit between the embryo and the maternal body. It is connected to the embryo by ........B....... It also acts as an ..........C........ tissue and secretes many hormones essential for maintaining pregnancy.

Options

A. A: placenta , B: chorionic villi, C: endocrine
B. A: placenta , B: umbilical cord , C: endocrine
C. A: placenta , B: umbilical cord , C: exocrine
D. A: placenta , B: chorionic villi, C: exocrine

Answer

To complete the paragraph, we need to fill in the blanks A, B, and C with the correct terms based on the context provided.

1. **Identifying Blank A**:
The blank states that it is the structural and functional unit between the embryo and the maternal body. The correct term for this is **placenta**. The placenta is indeed the organ that connects the developing embryo to the mother, facilitating nutrient and waste exchange.

2. **Identifying Blank B**:
The next part mentions that it is connected to the embryo by something. The correct term here is **umbilical cord**. The umbilical cord is the structure that connects the placenta to the embryo, allowing for the transfer of nutrients and oxygen.

3. **Identifying Blank C**:
The final blank states that it acts as a certain type of tissue and secretes hormones essential for maintaining pregnancy. The correct term for this is **endocrine**. The placenta functions as an endocrine tissue, producing hormones such as estrogen and progesterone, which are crucial for sustaining pregnancy.

Putting it all together, we can fill in the blanks as follows:

- A: **placenta**
- B: **umbilical cord**
- C: **endocrine**

The completed paragraph reads: "The placenta is the structural and functional unit between the embryo and the maternal body. It is connected to the embryo by the umbilical cord. It also acts as an endocrine tissue and secretes many hormones essential for maintaining pregnancy."