Final answer:
The Tuskegee Syphilis trials lasted for 40 years, from 1932 to 1972, and involved African American men who were intentionally not given the available treatment of penicillin for their syphilis. The study was widely criticized for its unethical nature and the harm it caused to the participants and their families.
Step-by-step explanation:
The Tuskegee Syphilis trials lasted for a period of 40 years, from 1932 to 1972. The study involved 600 African American men, including 399 who were diagnosed with syphilis. These men were not informed about their condition and were intentionally not provided with the available treatment of penicillin, in order to observe the progression of untreated syphilis. The study was widely criticized for its unethical nature and the harm it caused to the participants and their families.