Aminiocentesis is :-

Options

A. Analysis of chemical composition of fluids of pregnant woman
B. Withdrawal of allantoic fluid from pregnant
C. An in vitro diagnosis
D. Culturing of cells and study of metaphase chromosomes from amniotic fluid to identify chromosomal abnormality

Answer

**Step-by-Step Solution:**

1. **Understanding Amniocentesis**: Amniocentesis is a medical procedure used during pregnancy. It involves the extraction of amniotic fluid, which surrounds and protects the developing fetus.

2. **Purpose of Amniocentesis**: The primary purpose of this procedure is to test the amniotic fluid for genetic or chromosomal conditions. This can include testing for conditions like Down syndrome, Edwards syndrome, and Patau syndrome.

3. **Analyzing the Options**:
- **Option 1**: "Analysis of chemical composition of fluids of pregnant women" - This is incorrect because amniocentesis specifically involves amniotic fluid, not just any fluid.
- **Option 2**: "Withdrawal of allantoic fluid from pregnant" - This is also incorrect as amniocentesis does not involve allantoic fluid.
- **Option 3**: "An in vitro diagnosis" - This option is misleading. While amniocentesis is a diagnostic procedure, it is not considered in vitro since it involves extracting fluid from inside the body.
- **Option 4**: "Culturing of cells and study of metaphase chromosomes from amniotic fluid to identify the chromosomal abnormality" - This is the correct answer. Amniocentesis allows for the culturing of fetal cells from the amniotic fluid, which can then be analyzed for chromosomal abnormalities.

4. **Conclusion**: The correct definition of amniocentesis is the culturing of cells and study of metaphase chromosomes from amniotic fluid to identify chromosomal abnormalities.

**Final Answer**: Amniocentesis is the culturing of cells and study of metaphase chromosomes from amniotic fluid to identify chromosomal abnormalities.

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