What is placenta? Mention its role during pregnancy.

Explanation

**Step-by-Step Text Solution:**

1. **Definition of Placenta**: The placenta is a specialized tissue that forms during pregnancy. It serves as a vital connection between the developing embryo and the uterine wall of the mother.

2. **Connection Role**: The placenta acts as a bridge, linking the embryo to the mother. This connection is essential for the embryo's development, as it facilitates the exchange of substances between the mother and the embryo.

3. **Structure of the Placenta**: The placenta contains structures called villi. These villi increase the surface area available for absorption, making the transfer of nutrients and gases more efficient.

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