Placenta in human is

Options

A. Haemochorial
B. Metadiscoidal
C. Deciduous
D. All

Answer

### Step-by-Step Solution:

1. **Understanding the Types of Placenta**: The question asks about the type of placenta in humans. There are different classifications of placenta based on structure and function.

2. **Identifying Hemocoreal Placenta**: The human placenta is classified as hemocoreal. This means that there are three uterine tissue barriers present between maternal blood and fetal blood. These barriers include:
- **Endothelium of fetal blood vessels**: This is the innermost layer that lines the blood vessels of the fetus.
- **Trophoblast**: This is the outer layer of the blastocyst, which plays a crucial role in implantation and nutrient exchange.
- **Fetal connective tissue**: This layer provides structural support and is involved in the exchange of nutrients and waste.

3. **Identifying Meta-Discoidal Placenta**: The human placenta is also classified as meta-discoidal. This classification refers to the shape and distribution of the placenta. Initially, the placenta covers a larger area but later becomes restricted to one or two disc-shaped areas.

4. **Understanding Deciduous Placenta**: The human placenta is deciduous, meaning that a part of the placenta is shed during childbirth. This is a characteristic of the human placenta as it separates from the uterine wall during parturition.

5. **Conclusion**: Based on the classifications discussed, the correct answer to the question is that the human placenta is hemocoreal, meta-discoidal, and deciduous. Therefore, the correct option is "All of the above."

### Final Answer:
The placenta in humans is hemocoreal, meta-discoidal, and deciduous.

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