Final answer:
When a thrombus, an aggregation of blood constituents, is released into the bloodstream, it is referred to as an embolus. This can be critical if it leads to blockages in major organs, resulting in a medical emergency such as a heart attack or a stroke.
Step-by-step explanation:
When a thrombus, which is an aggregation of platelets, erythrocytes, and white blood cells trapped within fibrin strands, breaks free from the blood vessel wall, it enters the circulation and is then known as an embolus. Once an embolus is carried through the bloodstream, it can cause blockages in critical vessels. If the embolus becomes trapped in a major organ, such as the heart, brain, or lungs, it results in a medical emergency, leading to potentially life-threatening conditions like a heart attack, stroke, or pulmonary embolism.