This video tutorial provides an overview of the endocrine system (function, definitions, hormone classification and mechanism of action, target cell specificity, negative feedback).

• 0:28. Nervous system vs. Endocrine system
• 2:26. Endocrine glands vs. Exocrine glands
• 3:29. Definitions
• 4:08. Chemistry of hormones (peptide/steroid)
• 6:25. Mechanism of peptide hormones
• 8:36. Mechanism of steroid hormones
• 9:57. Hormone target cell specificity
• 13:26. Target cell activation
• 15:23. Negative feedback mechanism