A&P II Unit 1

List the 7 primary endocrine organs, 3 neuroendocrine organs, and 5 secondary endocrine tissues.

*primary endocrine organs:* 1) anterior pituitary gland 2) thyroid gland 3) 3-5 parathyroid glands 4) the adrenal cortex (x2) 5) endocrine pancreas 6) thymus 7) ovaries & testes *neuroendocrine organs:* 1) hypothalamus 2) pineal gland 3) posterior pituitary gland *secondary endocrine tissues:* 1) heart 2) kidneys 3) small intestine 4) adipose tissue/skin 5) liver

Briefly explain the relationship of the following sets of hormones, and the function of each of these hormones:

1) TRH/TSH/T4 & T3 = TRH from hypothalamus stimulates the secretion of TSH; TSH triggers the thyroid to produce T3 & T4 2) CRH/ACTH/glucocorticoids = CRH from hypothalamus stimulates the secretion of ACTH; ACTH stimulates the secretion of glucocorticoids from the adrenal cortex 3) PRH/PIH/Prolactin = PRH stimulates the secretion of prolactin while PIH inhibits prolactin secretion 4) GnRH/FSH & LH = GnRH stimulates the release of FSH & LH in both sexes which increases the levels of testosterone (males), estrogen & progesterone (females) 5) GHRH/GH/insulin-like growth factor = GHRH stimulates the secretion of GH; GH stimulates the production of IGF in children

Describe the origin and function of the four main proteins in blood plasma.

1) albumin = produced by the liver, responsible for the colloid osmotic pressure 2) immune proteins = aka antibodies, produced by the immune system, bind to antigens to target its removal 3) transport proteins = hydrophilic proteins that transport hydrophobic substances through the blood 4) clotting proteins = a collection of platelets & clotting proteins that form a blood clot to stop bleeding from an injured blood vessel

Describe the functions of the major representative of each of the type of hormones secreted by the adrenal cortex.

1) aldosterone = a mineralocorticoid that increases reabsorption of Na+ ions & water from the distal tubule, and the secretion of K+ & H+ ions 2) cortisol = a glucocorticoid that stimulates gluconeogenesis, fat & protein metabolism, & inhibits the inflammatory response 3) sex hormones (androgens) = an androgenic steroid that plays roles in reproductive maturation

Describe three physiological characteristics of protein-hormone complexes (bound hormones) in the blood.

1) allows hydrophobic hormones to be transported safely through the blood 2) gives the body a reservoir of hormones that can be released when needed 3) extends the lifespan of a hormone in the blood

Identify three primary cell types of pancreatic islet cells, and state the hormones they produce.

1) alpha cells --> glucagon 2) beta cells --> insulin 3) delta cells --> somatostatin

Name and describe the functions of the two hormone synthesized by the hypothalamus and stored in the posterior pituitary gland.

1) antidiuretic hormone (ADH) = controls water retention by causing the insertion of aquaporins in the cells of the distal tubule & collecting system to allow water reabsorption 2) oxytocin = stimulates the contraction of mamillary cells in nursing mothers to release milk; stimulate uterine contractions during childbirth

Describe the two major clotting disorders.

1) bleeding disorders = when the blood is unable to clot, often due to clotting protein deficiencies 2) hypercoagulable conditions = when blood clots form at improper times & tissue locations

Name two hormones secreted by the adrenal medulla.

1) epinephrine 2) norepinephrine

Name the three formed elements in blood.

1) erythrocytes (RBCs) 2) leukocytes (WBCs) 3) platelets

Explain the seven major functions of blood.

1) exchange gases 2) distribute solutes 3) perform immune functions 4) maintain body temperature 5) seal damaged blood vessels by forming blood clots 6) preserve acid-base homeostasis 7) stabilize blood pressure

Name the six releasing and inhibiting hormones synthesized by the hypothalamus that have an effect on the anterior pituitary gland.

1) gonadotropin-releasing hormone (GnRH) 2) thyrotropin releasing hormone (TRH) 3) corticotropin-releasing hormone (CRH) 4) growth hormone releasing hormone (GHRH) 5) prolactin releasing hormone (PRH) & prolactin inhibiting hormone (PIH) 6) somatostatin (GHIH)

List three stimuli for hormone secretion.

1) hormonal stimuli 2) humoral stimuli 3) neural stimuli

List four steps of hormone secretion.

1) hormones are secreted into the interstitial fluid, after which they diffuse into capillaries 2) the blood transports the hormones to the heart through the veins 3) after leaving the heart, blood transports the hormones to the rest of the body through arteries 4) in capillary beds, the hormones diffuse out of the blood, into the interstitial fluid, and bind to receptors on their target cells

List six functions of the hormones secreted by the adrenal medulla.

1) increases rate & force of heart contraction 2) dilates the bronchioles 3) constrict blood vessels supplying skin, digestive organs & urinary organs 4) dilate blood vessels supplying skeletal muscles 5) dilate pupils 6) decrease digestive & urinary functions

Name three pathways involved in fibrin formation.

1) intrinsic pathway = the part of the coagulation cascade in which all its factors are located within the blood already (aka contact activation pathway) 2) extrinsic pathway = part of the coagulation cascade that is initiated by a factor outside the blood called a tissue factor (aka tissue factor pathway) 3) common pathway = the convergence of the intrinsic & extrinsic pathways to produce fibrin

State the function of each of the following agranulocytes:

1) lymphocytes = has diverse functions in the immune system; has 2 types: B lymphocytes that are responsible for the antibody-mediated arm of adaptive immunity; T lymphocytes that are responsible for the cell-mediated arm of adaptive immunity 2) monocytes = the largest leukocyte; matures into macrophages that ingest dead & dying cells, bacteria, antigens, & other cellular debris; activate other parts of the immune system by displaying phagocytized antigens to other leukocytes

Describe the general functions of the endocrine system.

1) maintain fluid, electrolyte, & acid-base homeostasis 2) promote growth 3) regulate metabolic reactions 4) respond to stressors

Name three types of hormones secreted by the adrenal cortex.

1) mineralocorticoids --> regulate fluid, electrolyte, & acid-base balance 2) glucocorticoids --> stress response hormones 3) androgenic steroids --> sex hormones

State the function of each of the following granulocytes:

1) neutrophils = a very active phagocyte that ingests damaged cells & bacteria; most common leukocyte 2) eosinophils = involved in the immune response to parasites & in allergic reactions 3) basophils = least common leukocyte, involved in mediating inflammation

Describe three visible components of blood in centrifuged blood.

1) plasma (55%) = the fluid ECM of blood, composed of water, proteins, & dissolved solutes 2) buffy coat (1%) = leukocytes & platelets 3) erythrocytes (hematocrit, 44%)

List the three major functions of thyroid hormones in the body.

1) regulation of metabolic rate & thermoregulation 2) promotion of growth & development 3) synergism with SNS

List five effects of hormone action.

1) stimulate secretion from an endocrine or exocrine cell 2) activate or inhibit enzymes 3) stimulate or inhibit mitosis/meiosis 4) open/close ion channels in the plasma membrane or alter membrane potential 5) activate or inhibit gene expression

Briefly describe the long-term effect of growth hormone (GH) and IGF on all cells.

1) stimulates glucose uptake by cells 2) stimulates cell division --> bone & tissue growth 3) stimulates protein synthesis --> increased mass of muscle & other tissues

Explain five steps in a negative feedback look for hormone regulation (homeostasis).

1) stimulus: a regulated physiological variable deviates from its normal range 2) receptor: receptors on endocrine cells detect the deviation of the variable 3) control center: the stimulated control center (often the same endocrine cell) increases or decreases its secretion of a particular hormone 4) effector/response: the hormone triggers a response in its target cells that moves conditions towards the normal range 5) homeostatic range: as the variable returns to its normal range, feedback to the control center decreases the effector's response

Describe the negative feedback loop in control of erythropoiesis.

1) stimulus: the blood O2 level decreases below normal range 2) receptor: kidney cells detect a low O2 level 3) control center: kidneys produce more erythropoietin & release it into the blood 4) effector/response: production of erythrocytes increases 5) homeostasis: the blood level of O2 rises to normal

Name the six hormones synthesized by the anterior pituitary gland.

1) thyroid stimulating hormone (TSH) 2) adrenocorticotropic hormone (ACTH) 3) prolactin 4) luteinizing hormone (LH) 5) follicle stimulating hormone (FSH) 6) growth hormone (GH)

Name and describe two forms of thyroid hormones.

1) triiodothyronine (T3) = greater physiologic activity in promoting growth & development, regulating metabolic rate & heat production, & promoting effects of the SNS on target cells 2) thyroxine (T4) = less active form of the hormone that can be converted to T3 when needed

Name five steps of hemostasis.

1) vascular spasm (vasoconstriction) 2) platelet plug formation 3) coagulation 4) clot retraction 5) thrombolysis

Name the two primary components of blood plasma.

1) water (~90%) 2) plasma proteins (~9%)

Differentiate blood types A, B, AB, and O with regards to the surface antigen & the antibodies in the plasma.

A --> only A antigen, anti-B antibody B --> only B antigen, anti-A antibody AB --> both A & B antigens, no antibodies O --> no antigens, both anti-A & anti-B antibodies

Briefly explain the following disorders of adrenocortical hormone secretion - Cushing syndrome and Addison disease.

Cushing syndrome = the oversecretion of cortisol from the adrenal cortex, usually caused by a tumor; leads to rapid weight gain, increased BP, immune suppression, bone density loss Addison disease = hyposecretion of both cortisol & aldosterone; may be due to abnormal development of the adrenal gland, enzyme deficiency, or an autoimmune attack on the gland; increases risk of adrenal crisis & disrupts homeostasis

Differentiate between Rh negative and Rh positive.

Rh+ = has the Rh antigen present on erythrocytes Rh- = lacks the Rh antigen on erythrocytes

Briefly describe the structure and function of erythrocytes.

a biconcave disc-shaped cell that transports oxygen & CO2 on its hemoglobin

Describe the gross anatomy and cellular structure of the pancreas.

a club-shaped organ located in the abdominal cavity, posterior to the stomach; consists of 3 parts: head, body, tail; made up of 2 types of cells: pancreatic islets & acinar cells; pancreatic islets consist of alpha, beta, & delta cells

Define anemia and differentiate among three types of anemia.

a condition in which the O2 carrying capacity of the blood is reduced due to decreased hemoglobin, decreased RBCs, &/or abnormal hemoglobin 1) iron-deficiency anemia = due to low concentrations of iron in the body so hemoglobin cannot be made 2) pernicious anemia = due to vitamin B12 deficiency which interferes w/ DNA synthesis of hematopoietic cells 3) hemolytic anemia = due to the destruction of RBCs 4) aplastic anemia = due to the lack of RBCs produced by the red bone marrow

Using figure 19.19, Briefly explain the consequences of a mismatched blood transfusion.

a mismatched blood transfusion results in agglutination and thus hemolysis of the erythrocytes, because the body recognizes the mismatched blood as foreign due to the presence of the incorrect antigens or Rh factor present on the RBCs

Describe the location and anatomy of the adrenal gland.

a pyramidal shaped gland located on the superior end of both kidneys; consists of an outer cortex & an inner medulla the adrenal cortex has 3 distinct zones: zona glomerulosa --> zona fasciculata --> zona reticularis

Briefly explain the interaction between hydrophilic hormones and their target cell receptors with respect to the:

a. Location of receptors --> w/in cell membrane that opens a channel, or activates an enzyme or peripheral protein b. Cellular change that occurs --> activates a second-messenger system that begins a series of enzyme-catalyzed reactions resulting in the formation of a 2nd messenger c. Formation of products --> activate or inhibit chemicals that change events w/in the cell, open a channel, etc. d. Example: adenylate-cyclase-cAMP system

Briefly explain the interaction between hydrophobic hormones and their target cell receptors with respect to the:

a. Location of receptors --> w/in plasma membrane, cytosol, or nucleus b. Cellular change that occurs --> crosses plasma membrane & enters the cytosol of cells c. Formation of products --> forms hormone-receptor complex that bind to DNA & changes the rate of synthesis of products d. Example: thyroid hormones

Compare and contrast properties of amino-acid based hormones and steroid hormones.

amino-acid based hormones = chemical messengers consisting of 1+ amino acids; hydrophilic & bind plasma membrane receptors steroid hormones = chemical messengers derived from cholesterol, w/ a core of hydrocarbon rings; hydrophobic & interact with the plasma membrane or intracellular receptors

Define Rhesus (Rh) factor (surface antigen D).

an antigen present on the surface of erythrocytes, originally found in rhesus monkeys

Define the terms autocrine and paracrine secretion with respect to local signals.

autocrine = a chemical messenger that influences the function of the same cell or cell type that produced & secreted it paracrine = a chemical messenger secreted into the ECF to influence nearby target cells

Briefly explain why an individual with blood type O is called universal donor.

because erythrocytes with type O do not have any antigen of the ABO groups

Briefly explain why cortisol is sometimes called the "stress hormone".

because it plays a role in the stress response, since it increases the glucose level in the blood, creates another energy source for muscles in lipids, & has anti-inflammatory actions

Briefly explain why an individual with blood type AB is called universal recipient.

because the body does not produce antibodies to either the A or B antigens in type AB blood

Briefly explain the actions of thyroid hormones with regards to the following:

calorigenic effect & thermoregulation --> set the basal metabolic rate by increasing the synthesis of Na+/K+ pumps which raises ATP consumption gluconeogenesis -- > increases the production of glucose by the liver lipid metabolism --> increases the breakdown of fats in adipose tissue protein metabolism --> increases the breakdown of proteins in skeletal muscle

Name the major hormone secreted by the parathyroid gland gland and briefly explain the major function of this hormone.

chief cells secrete parathyroid hormone (PTH), which increases the concentration of calcium ions in the ECF

Compare and contrast the actions of the nervous system and endocrine system to control body functions.

endocrine system = synthesize & secrete hormones into the blood nervous system = operates through a series of neurons that directly affect their target cells through the release of NTs

Name the location of erythropoiesis in adults and the precursor cell.

erythropoiesis occurs in red bone marrow, and the precursor cells are hematopoietic stem cells

Name the hormone secreted by the kidneys that is involved in erythropoiesis.

erythropoietin (EPO)

Briefly explain why pancreas is considered as an exocrine and an endocrine gland.

exocrine function: produces enzymes that help with digestion endocrine function: secretes hormones that control the amount of sugar in the bloodstream

Briefly explain the benefits of erythrocytes being non-nucleated and without any organelles.

facilitates its transport of O2 through the blood by allowing more space for more hemoglobin molecules, & prevents the cell from using the O2 it carries

Name the final end-product from the common pathway.

fibrin

Briefly describe the role of platelets and fibrinogen in coagulation.

fibrinogen is converted into its active form fibrin by the coagulation cascade; fibrin is a sticky, threadlike protein that "glues" the formed elements & clotting factors together in a blood clot platelets trigger the coagulation cascade

Briefly describe the fate of the following substances during the process of erythrocyte destruction:

globin --> broken down into amino acids iron component of hemoglobin --> recycled to make more hemoglobin in red bone marrow heme group --> converted into the waste product biliverdin which is the converted into bilirubin

Name other solutes (dissolved and non-dissolved substances) found in blood plasma.

glucose, amino acids, nitrogenous wastes, ions, dissolved gases like O2 & CO2

Explain why the hematocrit is generally higher in males than in females.

hematocrit is usually 40-50% in males but 36-44% in females because males have a larger body size & greater muscle & bone mass

Briefly describe the formation of platelets.

hematopoietic stem cell --> myeloid cell line --> megakaryoblast --> megakaryocyte --> thrombopoietin causes "arms" of megakaryocytes to be looped off into the bloodstream creating cell fragments

Briefly compare the transport of hydrophobic and hydrophilic hormones in blood from their site of release to the target cells.

hydrophilic --> free hormones --> travel through blood hydrophobic --> bound hormones --> form complexes w/ binding proteins in the plasma

Define hyperglycemia and hypoglycemia.

hyperglycemia = elevated blood glucose level, usually due to insufficient insulin secretion or decreased insulin sensitivity hypoglycemia = a decrease in blood glucose levels, usually due to increased levels of insulin

Briefly explain the following disorders of thyroid hormone secretion - hyperthyroidism (Graves' disease), hypothyroidism, and goiter.

hyperthyroidism = overproduction of thyroid hormones; in Graves' disease, the immune system produces abnormal proteins that mimic TSH & stimulate the thyroid gland to overproduce T3 & T4; weight loss, heat intolerance, increased BP & HR hypothyroidism = underproduction of thyroid hormones; in Hashimoto's thyroiditis, the thyroid gland is destroyed by the immune system; weight gain, cold intolerance, decreased BP & HR goiter = enlargement of the thyroid gland; in hyper: by the abnormal proteins produced by the immune system that stimulate growth; in hypo: by the increased levels of TSH

Briefly explain the benefits of the concave shape and flexibility of erythrocytes.

it gives erythrocytes a large surface-to-volume ratio that is beneficial to their role in gas exchange, and allows them to fit through narrow blood vessels

Name the origin and precursor cell of leukocytes.

leukocytes also arise from hematopoietic stem cells in the bone marrow, which split into 2 cell lines: the myeloid cell line (monocytes & granulocytes) & the lymphoid cell line (lymphocytes)

Briefly explain the action of insulin on the cells in the following tissues:

liver tissue --> synthesis of glycogen all body cells & muscle cells --> uptake of amino acids, lipids & glucose from the blood brain tissue --> promotion of satiety & uptake of glucose

Describe the effect of cortisol on the following tissues:

liver/hepatocytes --> stimulates gluconeogenesis most cells including muscle cells --> release of amino acids adipose connective tissue --> release of fatty acids

Describe location and function of parafollicular cells in the thyroid gland.

located between thyroid follicles in the thyroid gland; produces calcitonin to decrease the blood calcium ion concentration

List the components of hemoglobin.

made up of 4 polypeptide subunits: 2 alpha chains, 2 beta chains; each polypeptide is bound to an iron containing compound called a heme group that binds to O2 to form oxyhemoglobin; in areas where O2 levels are low, hemoglobin releases O2 to become deoxyhemoglobin

Name the primary hormone secreted by this gland.

melatonin

Briefly describe the short-term effect of growth hormone (GH) on the following:

muscle cells --> inhibits glucose uptake liver --> stimulates gluconeogenesis adipose tissue --> stimulates lipolysis

Briefly explain the action of glucagon on cells in the following tissues:

muscle tissue --> protein breakdown to release amino acids for gluconeogenesis adipose tissue --> release of fats for gluconeogenesis & for an additional source of fuel liver tissue --> gluconeogenesis

State the location of the parathyroid gland.

on the posterior side of the thyroid gland are 3-5 small parathyroid glands

List the organs which are both primary and secondary endocrine organs.

ovaries & testes

Differentiate between oxygenated and deoxygenated blood.

oxygenated blood appears red because the more O2 that's bound to hemoglobin, the brighter the red RBCs become; in deoxygenated blood, few or none of hemoglobin's 4 subunits have O2 bound to it & thus is deoxyhemoglobin that appears a dark red/purple

State the location of the pineal gland.

part of the epithalamus of the diencephalon that acts as a neuroendocrine organ

Briefly explain the disorders of growth hormone secretion in pituitary gigantism and acromegaly.

pituitary gigantism = caused by the hypersecretion of GH before the epiphyseal plates close --> increases the size of all tissues, including muscle, organs, bones acromegaly = caused by the hypersecretion of GH after the epiphyseal plates close --> causes tissue increases in girth so some extremities & organs become enlarged

Briefly describe what happens when platelets adhere to the collagen fibers in a damaged blood vessel.

platelets aggregate over the injured blood vessel & are made "sticky" by vWF so they can adhere to collagen fibers, which then triggers platelet activation, which causes platelets to release the contents of its granules, which aggregate to form the platelet plug

Differentiate between primary and secondary organs of the endocrine system.

primary organs = organs that are part of the endocrine system that produce & secrete hormones secondary organs = organs not considered part of the endocrine system but produce hormones

Explain the effects of insulin on blood sugar.

promotes the uptake of glucose by cells which decreases blood sugar concentrations

Briefly explain the major function of this hormone.

regulates the sleep/wake cycle

Name the primary endocrine function of the pancreas.

secrete insulin & glucagon which control blood glucose levels

Define the following types of hormone interactions and provide one example for each type.

synergistic = multiple hormones that act on the same target cell to exert the same effect that is usually more pronounced; ex: prolactin & oxytocin antagonistic = multiple hormones that act on the same target cell but have opposite effects; ex: glucagon & insulin

Define hemoglobin.

the O2-binding protein in erythrocytes

Define hormone half-life.

the amount of time it takes for the plasma concentration of the hormone to reduce by half

Describe the location and anatomy of the thyroid gland.

the butterfly shaped gland, found in the anterior neck, just superficial to the larynx; consists of left & right lobes connected by the isthmus, and composed of small thyroid follicles, w/ parafollicular cells between them; on the posterior side of the gland are 3-5 small parathyroid glands

Name the function of platelets.

the cellular fragments of megakaryocytes that participates in blood clotting

Briefly describe the anatomic relationship of the hypothalamus and the pituitary gland.

the hypothalamus is the small anteroinferior portion of the diencephalon, which connects to the pituitary gland by a stalk called the infundibulum

Define hematocrit.

the portion of blood that consists of erythrocytes

Define thrombolysis.

the process by which a blood clot, or thrombus, is degraded

Define hemostasis.

the process by which blood loss is stopped from a damaged blood vessel

Differentiate between a thrombus and a thromboembolus.

thrombus = a blood clot thromboembolus = a portion of a thrombus that breaks off the original clot & travels to smaller vessels downstream and cause a blood clot there

Differentiate between Diabetes type I and Diabetes type II based on changes in pancreatic islets.

type I diabetes = caused by the destruction of the beta cells of the pancreas by the immune system so insulin is not produced; leads to hyperglycemia type II diabetes = the beta cells are fully functional but do not respond to normal increases in insulin & target cells are less responsive to insulin

Describe the general function of the following substances involved in blood coagulation:

vitamin K = involved in the synthesis of clotting factors II, VII, IX, & X fibrinogen = converted into the active form, fibrin, which glues the formed elements & clotting factors together in a blood clot calcium = activates factor X & prothrombin clotting factors = inactive proteins in the blood involved in the coagulation cascade thrombin = converts fibrinogen to fibrin