Heart attacks can be checked by using the enzyme …………………

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the name of an enzyme that can help check or prevent heart attacks.

2. **Identifying the Role of Enzymes in Heart Attacks**: Enzymes play a crucial role in various biochemical processes, including the breakdown of blood clots. Blood clots can block blood flow to the heart, leading to a heart attack.

3. **Finding the Correct Enzyme**: The enzyme that is commonly used to break down blood clots is called streptokinase. It is used in medical treatments to dissolve clots that can lead to heart attacks.

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