HA&P2 exam one class

Hormone

  • Definition: A chemical messenger secreted by glands to regulate physiological processes.

2. Target Cell

  • Definition: A cell that responds to a specific hormone because it has the appropriate receptors.

3. Receptor

  • Definition: A protein on a target cell that binds to a specific hormone to initiate a response.

4. Circulating vs. Local Hormones

  • Circulating Hormones: Travel through the bloodstream to distant target cells.

  • Local Hormones: Act near the site of secretion, without entering the bloodstream.

5. Paracrine vs. Autocrine Hormones

  • Paracrine Hormones: Affect neighboring cells.

  • Autocrine Hormones: Affect the same cell that secreted them.

6. Lipid-Soluble vs. Water-Soluble Hormones (Transport)

  • Lipid-Soluble Hormones: Travel bound to transport proteins in the bloodstream.

  • Water-Soluble Hormones: Travel freely in the bloodstream.

7. Lipid-Soluble vs. Water-Soluble Hormones (Mechanisms of Effect)

  • Lipid-Soluble Hormones: Bind to intracellular receptors, affecting gene expression.

  • Water-Soluble Hormones: Bind to cell surface receptors, triggering second messenger pathways.

8. Second Messenger

  • Definition: A molecule inside a cell that is activated by a hormone binding to a cell surface receptor, triggering a cascade of cellular events.

9. Signal Amplification

  • Definition: The process by which a small signal (e.g., hormone binding) leads to a large cellular response.

10. Effects of Hormones on Target Cells (Nucleus-related)

  • Alter gene expression

  • Stimulate protein synthesis

  • Influence cell growth

  • Regulate cellular metabolism

11. Effects of Hormones on Target Cells (Cytoplasm-related)

  • Alter cell metabolism

  • Stimulate secretion

12. Sub-Types of Hormones

  • Lipid-Soluble: Steroids, thyroid hormones

  • Water-Soluble: Peptides, amines

13. Up-Regulation

  • Definition: Increase in the number of receptors on a target cell, making it more sensitive to a hormone.

14. Down-Regulation

  • Definition: Decrease in the number of receptors on a target cell, reducing its sensitivity to a hormone.

15. Hormonal Interactions

  • Antagonistic: Hormones have opposite effects (e.g., insulin and glucagon).

  • Permissive: One hormone enhances the effect of another.

  • Synergistic: Hormones work together for a greater effect.

16. Endocrine Glands and Organs

  • Locations: Hypothalamus, pituitary gland, thyroid, parathyroid, adrenal glands, pancreas, gonads, pineal gland, thymus.

17. Regulatory Mechanisms of Hypothalamus on Pituitary

  • Hypothalamus releases hormones that stimulate or inhibit hormone release from the anterior pituitary and secretes oxytocin and ADH to the posterior pituitary.

18. Anterior Pituitary Cell Types & Hormones

  • Somatotrophs (GH), Lactotrophs (Prolactin), Corticotrophs (ACTH), Thyrotrophs (TSH), Gonadotrophs (LH and FSH).

19. Anterior Pituitary Hormones

  • Growth Hormone (GH), Prolactin (PRL), Adrenocorticotropic Hormone (ACTH), Thyroid-Stimulating Hormone (TSH), Luteinizing Hormone (LH), Follicle-Stimulating Hormone (FSH), Melanocyte-Stimulating Hormone (MSH).

20. Posterior Pituitary (ADH & Oxytocin)

  • ADH: Regulates water balance by promoting water reabsorption in the kidneys.

  • Oxytocin: Stimulates uterine contractions during childbirth and milk ejection during breastfeeding.

21. Thyroid & Parathyroid Glands

  • Thyroid: Produces T3 and T4 (thyroid hormones) that regulate metabolism; Calcitonin (lowers blood calcium).

  • Parathyroid: Produces parathyroid hormone (PTH), which increases blood calcium.

22. Adrenal Glands (Cortex & Medulla)

  • Cortex: Produces cortisol (stress response), aldosterone (sodium balance), and androgens (sex hormones).

  • Medulla: Produces adrenaline and noradrenaline (fight-or-flight response).

23. Pancreatic Islets

  • Alpha Cells: Produce glucagon (raises blood sugar).

  • Beta Cells: Produce insulin (lowers blood sugar).

  • Delta Cells: Produce somatostatin (regulates insulin and glucagon).

  • PP Cells: Produce pancreatic polypeptide.

  • Epsilon Cells: Produce ghrelin.

24. Ovaries, Testes, Pineal Gland, Thymus

  • Ovaries: Estrogen, progesterone.

  • Testes: Testosterone.

  • Pineal Gland: Melatonin.

  • Thymus: Thymosin.

25. Functions and Characteristics of Blood

  • Blood functions: Transport of gases, nutrients, waste products; regulation of temperature, pH; defense against infection.

26. Blood Components

  • Plasma, red blood cells (RBCs), white blood cells (WBCs), platelets.

27. Substances in Blood Plasma

  • Water, proteins (albumin, globulins, fibrinogen), electrolytes, nutrients, waste products, hormones, gases.

28. Hematocrit, Anemia, Polycythemia

  • Hematocrit: Percentage of blood volume occupied by RBCs.

  • Anemia: Low RBC count or hemoglobin.

  • Polycythemia: High RBC count.

29. Formed Elements

  • RBCs, WBCs, platelets; formed from hemocytoblasts.

30. Hemoglobin & RBC Life Cycle

  • Hemoglobin: Carries oxygen.

  • RBC life cycle: Produced in bone marrow, live 120 days, broken down in spleen.

31. Bilirubin, Transferrin, Ferritin

  • Bilirubin: Breakdown product of hemoglobin.

  • Transferrin: Iron transport protein.

  • Ferritin: Iron storage protein.

32. White Blood Cells (WBCs)

  • Types: Neutrophils, lymphocytes, monocytes, eosinophils, basophils.

33. Leukocytosis & Leukopenia

  • Leukocytosis: High WBC count.

  • Leukopenia: Low WBC count.

34. Platelets

  • Function: Blood clotting.

  • Structure: Small cell fragments.

35. Hemostasis & Hemorrhage

  • Hemostasis: Process of stopping bleeding.

  • Hemorrhage: Excessive bleeding.

36. Platelet Plug Formation

  • Step 1: Platelet adhesion.

  • Step 2: Platelet activation.

  • Step 3: Platelet aggregation.

37. Blood Clotting

  • Stages: Vascular spasm, platelet plug formation, coagulation.

38. Clotting Factors

  • Key factors: Fibrinogen, prothrombin, and others in the coagulation cascade.

39. Vitamin K in Clotting

  • Essential for the production of clotting factors.

40. Fibrinolytic System

  • Breaks down fibrin and dissolves clots.

41. Blood Group & Type

  • Blood group: Classification based on antigens on RBCs.

  • Blood type: Specific group (A, B, AB, O, Rh).

42. ABO & Rh Blood Groups

  • ABO: Based on A and B antigens.

  • Rh: Based on Rh factor (positive or negative).

43. Blood Type Differences

  • A, B, AB, O blood types; Rh+ and Rh- distinctions.

44. Sickle-Cell Anemia, Hemophilia, Leukemia

  • Sickle-Cell: Abnormal RBC shape.

  • Hemophilia: Lack of clotting factors.

  • Leukemia: Cancer of WBCs.

45. Blood Disorders

  • Thrombosis: Clot formation.

  • Embolus: Clot that travels.

  • Cyanosis: Bluish skin due to low oxygen.

  • Hemochromatosis: Iron overload.

  • Jaundice: Yellowing of the skin.

  • Septicemia: Blood infection.