The endocrine system is a diffuse collection of endocrine glands. The individual endocrine glands that make up this system include the pineal gland, the hypothalamus and pituitary gland, thyroid gland, thymus, pancreas, adrenal glands, and the gonads. All of these endocrine glands produce and secrete hormones that have various effects on the body.

This system includes the pineal and pituitary glands in the head, the thyroid gland in the neck, the thymus in the chest, the adrenal gland and pancreas in the abdomen, and the gonads in the pelvis.

Figure 1: The endocrine system.