Endocrine system study guide Endocrine vs. exocrine glands. Paracrine and autocrine effects. Classification of hormones by chemical structure: water-soluble and lipid-soluble, know examples of each class. Hormone receptors – their location and functions. Target cells specificity. Receptor mechanisms. Second messengers and direct gene regulation. Receptor downregulation and its role. Regulation of endocrine system: hypothalamo-pituitary hormones, metabolites, ANS. Specific glands – know location, general structure, which hormones they make and the effects of these hormones: Hypothalamus Pituitary gland: anterior and posterior Pineal gland Thyroid Parathyroid Pancreas Adrenals: cortex and medulla Gonads Hormones made by other (non-endocrine) organs: heart, liver, kidney, digestive system, adipose tissue. Common endocrine disorders. Pathologies associated with pituitary hormones excess or insufficiency. The best way to practice is to write down complete answers for each question. Try to answer the questions from memory, like it is a real exam. If you don’t know the answer right away you can look it up in the notes or textbook. If you still cannot find an answer, make a note about it and we will discuss it during the review session before the exam. Practice questions 1. Explain the main principles the endocrine system operation. Endocrine glands Specialized organs that make hormones; secrete them into the blood. Purely endocrine glands do not have ducts o Pituitary gland o Thyroid gland o Adrenal gland Hormones Biologically active substance release by a specialized cell and affecting the function of other cells Receptors
Only cells with receptors will respond to a hormone. Receptors are always proteins, are very specific-respond to only one kind of hormone. A cell with receptors for a hormone is called a target cell for that hormone. 2. Explain the difference between an endocrine and an exocrine gland; give examples of exocrine glands. Endocrine Glands Do not have ducts, make hormones and secrete them into the blood Exocrine Glands Have ducts, secrete hormones onto the surfaces of the body. o Salivary glands- saliva o Sebaceous glands- skin oil o Lacrimal glands- tears o Digestive glands of the stomach- digestive enzymes 3. Give an example of a gland that has both exocrine and endocrine functions. 4. Give examples of some organs that are not specialized endocrine glands but produce hormones. Heart- ANP Kidney- EPO and renin Adipose tissue- leptin Skin- cholecalciferol 5. Explain the term “paracrine” – how is it different from “endocrine”? Paracrine- have only local effects- affects cells in the same tissue only. o prostaglandins Endocrine- secreted in the blood, have systemic effects- affects cells at other locations in the body. Some endocrine hormones can also have paracrine effects 6. Explain the terms “antagonistic effect”, “synergistic effect” and “permissive effect” as related to hormone action.