Diabetes is a disease caused by an insulin shortage or defective insulin receptors. Many people with this illness must give themselves insulin injections to keep their blood sugar levels from getting too high. When it is uncontrolled, diabetes may lead to other dangerous health problems, such as increased risk of heart attacks, strokes, and blindness. They produce eggs and sperm, the cells that join to form an embryo. Gonads also make reproductive hormones.
Testes produce testosterone , and ovaries produce estrogen and progesterone .
These hormones are necessary for the growth of eggs and sperm. In addition, they cause the development of some of the characteristics that make men and women look different from each other. One of the well known effects of testosterone is that it stimulates muscle growth. However, these drugs have other dangerous side effects, and their use is illegal. The thymus makes a hormone, called thymosin, that stimulates the growth of certain immune cells.