Hormones are the chemical messengers in the body that travel the bloodstream to the organs and tissues. They slowly work and affect many of the body's processes over time. Endocrine glands, which are special groups of cells, make hormones.There are many endocrine glands in the body with the main ones being the pituitary gland, thyroid, thymus, adrenal glands, and the pancreas. Hormones are dominant and it only requires a small amount of them to cause significant changes throughout the body. Both men and women produce hormones in the same areas with one exception, the sexual organs. Additional male hormones are produced in the testes while women's are produced in the ovaries.