BIOL 2402 Chapter 17 Learning Objectives PDF

**Chapter 17: READING IN SALADIN** - Read all of the chapter EXCEPT for Deeper Insight 17.3 which you may omit; be sure to read page 649 - As you review the lecture slides, be prepared to explain the content in your own words (you are responsible for the details in every figure unl...

**Chapter 17: READING IN SALADIN** - Read all of the chapter EXCEPT for Deeper Insight 17.3 which you may omit; be sure to read page 649 - As you review the lecture slides, be prepared to explain the content in your own words (you are responsible for the details in every figure unless instructed otherwise; this holds true for *every* chapter) **Chapter 17 Objectives** 1. Match the characteristics of the nervous vs. endocrine system (Table 17.1) - Nervous system: communicates by means of electrical impulses and neurotransmitters; endocrine: communicates by means of hormones - Nervous: releases neurotransmitters at synapses at specific target cells; endocrine: releases hormones into bloodstream for general distribution throughout body - Nervous: usually has relatively local, specific effects; endocrine: sometimes has very general, widespread effects - Nervous: reacts quickly to stimuli, usually within 1-10 ms; endocrine: reacts more slowly to stimuli, often taking seconds to days - Nervous: stops quickly when stimulus stops; endocrine: may continue responding long after stimulus stops - Nervous: adapts relatively quickly to continual stimulation; adapts relatively slowly; may respond for days to weeks 2. Differentiate between paracrine, autocrine, and "direct communication" (gap junctions) - Paracrine action: you have a cell that releases signal molecules and affects some cells; examples: histamine (leaky vasodilation) - Autocrine action: hepcidin inhibits intestinal iron absorption (endocrine); hepcidin also "reminds" liver not to release any stored iron - example: iron is too high so hepcidin decreases absorption of iron -\> hepcidin goes back to liver; reminds liver cell to not release iron - gap junctions: biochemical direct communication between cells 3. Identify the steps of the biochemical pathway in the production of eicosanoids and distinguish between the actions of SAIDS and NSAIDS - Phospholipid -\> phospholipase -\> AA -\> lipoxygenase (leukotrienes allergic) and cyclooxygenase (prostacyclin, thromboxanes -- clotting, prostaglandins) - SAIDS: non-steroidal - NSAIDS: steroidal anti-inflammatory 4. Distinguish between endocrine organs, neuroendocrine organs, and secondary endocrine organs - Endocrine organs: anterior pituitary gland; hypothalamus, pineal gland, posterior pituitary & gland (neuroendocrine organs), thyroid gland, parathyroid gland, thymus gland, adrenal cortex; adrenal medulla (neural origin), pancreas, ovaries, testes - Secondary endocrine organs: skin, liver, kidney, heart, adipose tissue, GI tract (stomach and small intestine), osseous tissue, placenta 5. Identify examples of each of the three classes of hormones and predict how they travel through blood and if they can pass through a phospholipid bilayer - Cholesterol derivatives (hydrophobic), amino acid derivatives, peptides and glycoproteins made from chains of amino acids 6. Distinguish between the processes used to synthesize hormones for each class of hormone - Synthesis of steroid hormones: derive from cholesterol---each hormone has the same 4-ring backbone, but different functional groups (hydrophobic); can easily pass through membranes, need a carrier traveling in blood - Synthesis of peptide hormones: same as any peptide/protein; resulting peptide can be modified in RER and Golgi; do not need a carrier in blood; cannot easily pass through membranes - Synthesis of monoamines: monoamines start with one amino acid, either tyrosine or tryptophan; do not need a carrier in blood, cannot easily pass through membranes 7. Distinguish between, and recognize examples of hormonal, neural, and humoral stimulation of hormone secretion - Hormonal stimulus: the hypothalamus secretes hormones that stimulate the anterior pituitary gland to secrete hormones that stimulate other endocrine glands to secrete hormones - Neural stimulus: preganglionic sympathetic fibers stimulate adrenal medulla cells to secrete catecholamines (epinephrine and norepinephrine) - Humoral stimulus: capillary blood contains low concentration of Ca2+, which stimulates secretion of parathyroid hormone (PTH) by parathyroid glands. PTH acts to increase blood Ca2+ 8. Identify hormones and hormone categories that require carrier proteins for transport in the blood vs. those that do not - Steroid hormones: hydrophobic - Thyroid hormones: hydrophobic - Monoamines and peptides: hydrophilic - Carrier proteins protect circulating hormones from: circulating enzymes that may digest hormones; being filtered out of blood by kidneys; breakdown by the liver 9. Identify the characteristics of specificity and saturation regarding receptors on target cells - Specificity: one type of receptor only binds one type of hormone - Saturation: a) the more receptors bound to hormone, the greater the response, b) once all receptors bound to hormone, no additional hormone can bind & maximal response achieved 10. Identify the possible locations of hormone receptors for each structural category of hormone (and what characteristic of biological membranes makes it necessary to have different locations) - 11. Place in order the steps involved in the transduction process that uses cAMP as a second messenger - 1\. Hormone-receptor binding activates G protein - 2\. G protein activates adenylate cyclase - 3\. Adenylate cyclase produces cAMP - 4\. cAMP activates protein kinases - 5\. Protein kinases phosphorylate enzymes - 6\. Activated enzymes promote metabolic reactions with a wide range of possible effects on the cell 12. Place in order the steps for IP3 and DAG as "alternate" second messenger systems - Begins with a phospholipid in the membrane - Activated G protein triggers the enzyme phospholipase to split a phospholipid into 2 fragments (IP3 and DAG) - Diacylglycerol: activates protein kinase - Inositol triphosphate system: intracellular Ca2+ 13. Identify potential metabolic effects of second messenger systems - Activation or deactivation of enzymes - Increase or decrease in amount of protein synthesis in cell - Influence on glycogen metabolism (glycogenesis or glycogenolysis) - Stimulation of mitosis - Stimulation of apoptosis - Promote differentiation - Activation or inhibition of membrane channels (via ligand or change in membrane potential) - Smooth muscle contraction - Secretion of product 14. Order the steps involved in the transduction process utilized by hydrophobic hormones - 15. Identify examples of upregulation and downregulation of target cell receptors - Up-regulation: stronger response (low receptor density; weak response increase receptor density; increase sensitivity) - Down-regulation: diminished response (high receptor density; strong response reduced receptor density reduced sensitivity) 16. Identify examples of hormone interactions (synergistic, permissive, antagonistic) - Synergistic effects: hormones work together to produce greater effect; FSH and testosterone on sperm production - Permissive effects: first hormone allows action of second hormone; estrogen permits effects of progesterone - Antagonistic effects: first hormone causes opposite effect of another hormone; calcitonin and parathyroid hormone on blood calcium levels 17. Identify the use of feedback loops in hormonal, neural and humoral control of hormones - Hypothalamus anterior pituitary gland peripheral endocrine gland target cells action - Nervous system endocrine gland target cells action - Changing level of substance in plasma endocrine gland target cells action - Each of these stimulating factors can be regulated by feedback loops, usually negative 18. Identify the anatomical relationships between the hypothalamus and pituitary gland - Hypothalamus: regulates primitive functions -- ex. H2O balance, thermoregulation, sex drive, childbirth - Pituitary gland: secretes hormones as dictated by the hypothalamus - Composed of 2 structures of independent origins and separate functions: - Adenohypophysis, AKA anterior pituitary - Neurohypophysis, AKA posterior pituitary - Hypothalamic neurons secrete releasing and inhibiting hormones into the hypothalamic capillary bed - Hormones travel through portal veins in the infundibulum - Hypothalamic hormones exit the anterior pituitary capillary bed to bind to receptors on anterior pituitary cells - Hypothalamic hormones stimulate or inhibit secretion of hormones from the anterior pituitary cells - Hypothalamic-hypophyseal portal system: hypothalamic capillary bed, portal veins, anterior pituitary capillary bed 19. List the 8 hormones produced by the hypothalamus - Corticotropin-releasing hormone (CRH): adrenocorticotropic hormone; target organ---adrenal cortex - Gonadotropin-releasing hormone (GnRH): luteinizing hormone (LH) & follicle-stimulating hormone (FSH); target organ---ovaries, testes - Growth hormone-releasing hormone (GHRH): growth hormone (GH) (trophic); target hormone---muscles, cartilage, bone, adipose, liver - Prolactin-inhibiting hormone (PIH): inhibits prolactin (PRL); target organs---mammary glands - Somatostatin: inhibits growth hormone (GH) and thyroid-stimulating hormone (TSH); target organs---same as above; thyroid glands - Thyrotropin-releasing hormone (TRH): thyroid-stimulating hormone (TSH) and increase in prolactin (PRL); target organs---thyroid glands 20. List the six hormones synthesized by the pituitary gland and the additional two that are released from the pituitary gland - Follicle-stimulating hormone (FSH), luteinizing hormone (LH), thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), prolactin (PRL), growth hormone (GH) - Additional two: antidiuretic hormone (ADH), oxytocin (OT) 21. Starting with cells in the hypothalamus and ending with the release of each of six hormones from the anterior pituitary gland, order the steps involved in the hypoththalamic-hypophysial portal system - 22. Starting with cells in the hypothalamus and ending with the release of each of two hormones from the posterior pituitary gland, order the steps involved - 23. For the two hormones released by the posterior pituitary, recognize the stimulus for release, the type of control, the target tissues, effects, and mechanism of feedback control - Antidiuretic Hormone (ADH): - Osmoreceptors detect low solvent concentration and/or high solute concentration - Vasopressin: vasoconstriction causes increase in blood pressure - Stimulus: high solute concentration, low water concentration in plasma - Type of control: receptors -- osmoreceptors in hypothalamus; response -- ADH release from posterior pituitary into blood - Target issues: kidney tubules, smooth muscle, sweat glands - Effects: increased absorption of water from kidney tubules, vasoconstriction of blood vessels (at high concentrations of ADH), decreased sweat produced - Mechanism of feedback control: negative feedback to decrease release of ADH - Oxytocin (OT): - Stimulus: activation of stretch receptors or myoepithelial cells - Type of control: receptors -- mechanoreceptors in cervix or breast tissue; response -- OT release from posterior pituitary into blood - Target issues: smooth muscle of uterus or myoepithelial cells in breast tissue - Effects on target issues: contraction of smooth muscle in uterine wall; "let down" of milk - Mechanism of feedback control: positive feedback to increase OT until stimulus stops (birth or infant stops sucking) 24. Identify the components of pituitary gland regulation by the hypothalamus and target organs (hypothalamo-pituitary-target signal axis) - Corticotropin-releasing hormone - Pituitary hormone: + adrenocorticotropic hormone - Target structure/organ: adrenal cortex - Gonadotropin-releasing hormone - Pituitary hormone: + follicle-stimulating hormone, + luteinizing hormone - Target structure/organ: ovaries and testes - Growth-hormone-releasing hormone - Pituitary hormone: + growth hormone - Target structure/organ: liver, bone, cartilage, muscle, fat - Prolactin-inhibiting hormone - Pituitary hormone: - Prolactin - Target structure/organ: mammary glands - Somatostatin - Pituitary hormone: - growth hormone and thyroid stimulating hormone - Target structure/organ: liver, bone, cartilage, muscle, fat - Thyrotropin-releasing hormone - Pituitary hormone: thyroid-stimulating hormone; Prolactin - Target structure/organ: thyroid gland 25. Starting with TRH, CRH, GnRH, GHRH, (PIH, somatostatin), differentiate among the stimuli for their release, pituitary hormones produced in response, anatomy of target organs, (production of thyroid hormone and its use of iodine), hormones released by target organs, actions of target organ hormones, feedback mechanisms that regulate further release of hormone, disorders that arise from either hyposecretion or hypersecretion at any "tier" - 26. The target organs (or glands embedded in the target organs -- parathyroid glands) considered above also have endocrine function that is not part of the hypothalamic-pituitary-target organ axis. For calcitonin, parathyroid hormone, epinephrine/norepinephrine, aldosterone, differentiate among the stimuli for their release, target organs, effects, results of hyposecretion or hypersecretion - 27. Distinguish between hormones released from pineal gland and thymus and their actions - Pineal gland: - melatonin -- promotes sleep, may have antioxidant and anticancer properties; may influence timing of puberty in humans; synchronizes physiological function with 24 hr circadian rhythms of daylight and darkness; at night -- pineal gland synthesizes melatonin from serotonin - Thymus: - thymopoietin, thymosin, and thymulin -- development of other lymphatic organs and activity of T lymphocytes 28. Identify the cell types found in the pancreatic islets of the pancreas; identify their function - Alpha cells: secrete glucagon - Beta cells: secrete insulin - Delta cells: secrete somatostatin 29. Identify the signs/symptoms of diabetes mellitus and the pathologies that result; distinguish between "type 1" and "type 2" diabetes - Diabetes mellitus: - 1\. Polyuria (excessive urination) - 2\. Polyphagia (increased appetite) - 3\. Polydipsia (excessive thirst) - Type 1: pancreas's failure to produce enough insulin due to loss of beta cells - Type 2: insulin resistance contributes to high glucose levels in the blood 30. Identify the components of the General Adaptation Syndrome (GAS) - Stress, situation that upsets homeostasis and threatens one's physical or emotional well-being - Injury, surgery, infection, intense exercise, pain, grief, depression, anger, etc - GAS: consistent way body reacts to stress; typically involves elevated levels of epinephrine and glucocorticoids, esp. cortisol - Occurs in 3 stages: alarm reaction, stage of resistance, stage of exhaustion 31. Identify the endocrine function of the following tissues/organs: skin, liver, kidneys, heart, stomach/small intestine, adipose tissue, osseous tissue, placenta - Skin: uses UV light to start synthesis of vitamin D by producing cholecalciferol - Liver: converts cholecalciferol to calcitriol, secretes angiotensinogen. (a "prohormone"), secretes 15% of erythropoietin, secretes hepcidin (regulates plasma iron levels), source of IGF-I that controls action of growth hormone - Kidney: converts calcidiol to calcitriol, secretes hormones that regulate blood cell production and rates of calcium/phosphate absorption by intestinal tract - Heart: secretes hormones involved in regulating blood volume - GI tract, enteroendocrine tissue secrete at least 10 enteric hormones (coordinate digestive motility, glandular secretion and appetite) - Adipose tissue: regulates appetite - Osseous tissue: secretes hormones that regulate insulin secretion/sensitivity - Placenta: secretes hormones that regulate pregnancy 32. Match the effects of endocrine system hormones to other organ systems (page 659) - In class lab activity answers: 11\) D 12\) B 13\) D 14\) E 15\) E 16\) A 17\) B 18\) D 19\) E 20\) C 21\) D 22\) A 23\) A 24\) A 25\) E