Endocrinology is the study of hormones, their signaling pathways, and the diseases associated with them. The endocrine system is one of two mechanisms in the human body that is responsible for regulating and integrating the function of cells, the other being the nervous system.
Hormones are classified into three types, according to their chemical composition:
Peptide hormones produced by secretory nervous tissue are known as neuropeptides.
A disease due to a disorder of the endocrine system is often called a "hormone imbalance" and is usually caused by hypo- or hyperfunction of an endocrine gland. Better known examples include Acromegaly, Cushing Syndrome, Diabetes, Dwarfism, Graves Disease, Hermaphroditism, Delayed and Precocious Puberty, and Thyroid Diseases.