what are hormones?

• They are organic chemical substance(usually proteins or steroids).hormones are secreted by ductless and endocrine glands directly into the blood stream
• Hormones performs several biological functions such as;
• Insulin for lowering blood glucose concentration
• Anti-diuretics hormone, ADH for promoting reabsorption of water in the kidney
• Gastric stimulate the secretion of gastric juice etc. The name is derive from a Greek word meaning it arouses to activity
• Each hormones has its own target cell on which it acts; therefore each has its own specific effect on the body
• Hormones are often effective in very small concentrations
• Most hormones are either excreted in the urine or broken down by enzymes quite quickly.