Ovulation is induced by a hormone called the __________.

Answer

**Step-by-Step Solution:**

1. **Understanding Ovulation**: Ovulation is defined as the process of releasing an ovum (egg) from the ovaries into the fallopian tube. This is a crucial part of the female reproductive cycle.

2. **Timing of Ovulation**: Ovulation typically occurs around the 13th to 15th day of the menstrual cycle. This timing is important for understanding the hormonal changes that facilitate ovulation.

3. **Identifying the Hormone**: The hormone responsible for inducing ovulation is known as the luteinizing hormone (LH).

4. **Role of Luteinizing Hormone (LH)**: During ovulation, there is a significant increase in the secretion of LH. This surge in LH levels is what triggers the ovulation process.

5. **Mechanism of Action**: The rapid secretion of LH leads to the rupture of the Graafian follicle (the mature follicle), which releases the egg. This rupture is a key event in the ovulation process.

6. **Conclusion**: Therefore, the hormone that induces ovulation is called luteinizing hormone (LH).

**Final Answer**: Ovulation is induced by a hormone called the **luteinizing hormone (LH)**.

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