Menstrual cycle occurs in

Options

A. Female primates
B. Human females
C. Mammalian females
D. Rabbit

Answer

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

1. **Understanding the Menstrual Cycle**: The menstrual cycle is a monthly cycle that occurs in female primates, including humans. It typically lasts around 28 days and involves the preparation of the uterus for potential pregnancy.

2. **Classification of Mammals**: Mammals are classified into two main groups: primates and non-primates. Primates include species such as humans, monkeys, and apes, while non-primates include other mammals like dogs, cats, and horses.

3. **Menstrual Cycle in Primates**: In primates, the menstrual cycle occurs when the endometrium (the inner lining of the uterus) thickens in preparation for a fertilized egg. If fertilization does not occur, the endometrium is shed, resulting in menstrual bleeding.

4. **Non-Primate Mammals**: In contrast, non-primate mammals do not undergo a menstrual cycle. Instead, they experience an estrous cycle, where the endometrium is reabsorbed if fertilization does not take place.

5. **Analyzing the Options**: The question provides several options:
- Female primates
- Human female
- Mammalian female
- Rabbit

Among these, "female primates" is the most accurate choice since it encompasses all primates that experience a menstrual cycle, including humans.

6. **Conclusion**: Therefore, the correct answer to the question "Menstrual cycle occurs in" is **female primates**.

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