Final answer:
Internists or internal medicine specialists include cardiologists and endocrinologists, who concentrate on diseases of the heart and endocrine systems, respectively, after extensive medical schooling and training.
Step-by-step explanation:
Physicians who specialize in the diagnosis and treatment of diseases related to the internal organs are known as internists or specialists in internal medicine. Among these, are cardiologists and endocrinologists, who undergo extensive training to hone their skills in their respective areas. Cardiologists focus on heart-related conditions following 4 years of medical school and several additional years of specialized training, ultimately becoming board-certified after rigorous examinations. Endocrinologists deal with endocrine system disorders involving hormone systems such as diabetes and thyroid disease after similar lengths of training and certification. Both roles are essential for the treatment and management of internal organ diseases and require a strong background in internal medicine.