Why is easy bruising so common in older adults? Most bruises form when small blood vessels (capillaries) near the skin's surface are broken by the impact of a blow or injury â often on the arms or legs. When this happens, blood leaks out of the vessels and initially appears as a black-and-blue mark. Eventually your body reabsorbs the blood, and the mark disappears.
HeLa cell. HeLa cell, a cancerous cell belonging to a strain continuously cultured since its isolation in 1951 from a patient suffering from cervical carcinoma. The designation HeLa is derived from the name of the patient, Henrietta Lacks.
Lacks's cells â known as HeLa, using the first two letters of each of her names â became the first immortal human cell line in history. Scientists at the hospital where she died, Johns Hopkins in Baltimore, had been working for years to try to start a continuously reproducing cell line â but the cells always died.