Soluble inorganic and organic nutrient material, hormones, antibodies, against diptheria, smallpox, scarlet fever, measles etc. can pass from the mother to the foetus, so we can say that placenta act as a –

Options

A. Endocrine gland
B. Barrier
C. Ultra filter
D. All of above

Answer

To solve the question regarding the functions of the placenta in transferring nutrients and antibodies from the mother to the fetus, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Placenta's Role**: The placenta is a vital organ that forms during pregnancy, connecting the developing fetus to the uterine wall. It facilitates the exchange of nutrients, gases, and waste between the mother and fetus.

2. **Nutrient Transfer**: The placenta allows soluble inorganic and organic nutrients to pass from the mother to the fetus. This includes essential nutrients required for fetal growth and development.

3. **Hormone Transfer**: Hormones produced by the mother can also cross the placenta. These hormones play crucial roles in regulating pregnancy and supporting fetal development.

4. **Antibody Transfer**: The placenta is capable of transferring antibodies from the mother to the fetus, providing the fetus with passive immunity against certain diseases such as diphtheria, smallpox, scarlet fever, and measles.

5. **Functions of the Placenta**:
- **Endocrine Gland**: The placenta acts as an endocrine gland by producing hormones that regulate various aspects of pregnancy.
- **Barrier**: It serves as a barrier that protects the fetus from harmful substances and pathogens while allowing necessary substances to pass through.
- **Ultrafilter**: The placenta functions as an ultrafilter, selectively allowing certain substances to pass while filtering out waste products and toxins.

6. **Conclusion**: Given that the placenta performs all these functions, the correct answer to the question is that the placenta acts as "all of the above" - an endocrine gland, a barrier, and an ultrafilter.

### Final Answer:
The placenta acts as an endocrine gland, barrier, and ultrafilter, so the correct answer is "all of the above."

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