Read the following and select the incorrect statements:
A. The placenta acts as a permanent endocrine tissue and produces several hormones.
B. During pregnancy levels of cortisol, prolactin, thyroxine, and estrogen hormones also Increase several folds in maternal blood.
C. The second meiotic division of secondary spermatocyte in females is unequal and results in the formation of a polar body.
D. The secondary follicle transforms into a tertiary follicle which is characterized by a fluid - filled cavity called the antrum.

Options

A. B & D only
B. A & c only
C. A & B only
D. A, B & C

Answer

To solve the question, we need to analyze each of the four statements provided and determine which ones are incorrect.

### Step-by-Step Solution:

1. **Statement A**: "The placenta acts as a permanent endocrine tissue and produces several hormones."
- **Analysis**: The placenta is not a permanent endocrine tissue; it is a temporary endocrine organ that forms during pregnancy. It does produce several hormones, such as HCG, progesterone, and estrogen, but it is not classified as a permanent endocrine tissue.
- **Conclusion**: This statement is **incorrect**.

2. **Statement B**: "During pregnancy levels of cortisol, prolactin, thyroxine, and estrogen hormones also increase several folds in maternal blood."
- **Analysis**: While prolactin, thyroxine, and estrogen levels do increase during pregnancy, the statement regarding cortisol is misleading. Cortisol levels do not necessarily increase significantly during pregnancy; they can fluctuate based on various physiological conditions. Therefore, this statement is partially incorrect due to the mention of cortisol.
- **Conclusion**: This statement is **incorrect**.

3. **Statement C**: "The second meiotic division of secondary spermatocyte in females is unequal and results in the formation of a polar body."
- **Analysis**: This statement is about oogenesis, not spermatogenesis. In females, during oogenesis, the secondary oocyte undergoes an unequal second meiotic division, resulting in one large ovum and a smaller polar body. This statement correctly describes the process.
- **Conclusion**: This statement is **correct**.

4. **Statement D**: "The secondary follicle transforms into a tertiary follicle which is characterized by a fluid-filled cavity called the antrum."
- **Analysis**: This statement accurately describes the development of ovarian follicles. The secondary follicle does develop into a tertiary follicle (also known as a Graafian follicle), which is characterized by the formation of an antrum, a fluid-filled cavity.
- **Conclusion**: This statement is **correct**.

### Final Answer:
The incorrect statements are **A and B**.