.................. are involved in blood clotting at the injury.

Explanation

**Step-by-Step Solution:**

1. **Understanding Blood Clotting**: Blood clotting, also known as coagulation, is a vital process that prevents excessive bleeding when there is an injury to a blood vessel.

2. **Identifying the Components**: When an injury occurs, several components in the blood work together to form a clot. The primary components involved in this process are platelets.

3. **Role of Platelets**: Platelets, also known as thrombocytes, are small, colorless cell fragments found in the blood. They play a crucial role in the blood clotting process by aggregating at the site of injury and forming a temporary plug to stop bleeding.

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