front 1 Blood vessels are ___ | back 1 Dynamic anatomical structures that maintain efficient blood flow via a variety of fascinating physiological processes |
front 2 Sort these vessel types in the order of blood flow, starting with those that first carry blood away from the heart and finishing with those that eventually return blood to the heart | back 2 - Arteries - Arterioles - Capillaries - Venules - Veins |
front 3 Arteries | back 3 Carry blood away from the heart and branch into progressively smaller structures |
front 4 Arterioles | back 4 The smallest of the structures and deliver blood to capillaries |
front 5 Capillaries | back 5 Gets blood from arterioles which serve the organs and tissues of the body (systemic circuit) or the lungs (pulmonary circuit) |
front 6 Venules | back 6 Collect blood from capillary networks and then converge to form progressively larger structures, the veins |
front 7 Veins | back 7 Eventually return blood to the heart |
front 8 Arteries carry oxygenated blood, veins carry deoxygenated blood | back 8 Systemic circuit |
front 9 Arteries carry deoxygenated blood, veins carry oxygenated blood | back 9 Pulmonary circuit |
front 10 Arteries and arterioles carry blood ___ from the heart | back 10 Away |
front 11 Veins and venules carry blood ___ the heart | back 11 Toward |
front 12 Which blood vessels carry oxygenated blood? | back 12 - Pulmonary veins - Systemic arteries |
front 13 Arrange the layers of a blood vessel wall, from superficial to deep | back 13 - Tunica externa - Tunica media - Tunica intima |
front 14 What is the likely problem the patient is suffering from (pain is excruciating and tearing)? | back 14 Aortic dissection (tearing) |
front 15 Tunica intima (tissue type) | back 15 Simple squamous endothelium |
front 16 Tunica media (tissue type) | back 16 Smooth muscle and elastic connective tissue |
front 17 Tunica externa (tissue type) | back 17 Collagenous connective tissue |
front 18 Aorta and its principle branches are considered to be | back 18 Elastic arteries and conducting arteries |
front 19 Why must the aorta and its branches be able to stretch and recoil so readily? | back 19 The arteries must be able to stretch when pressure rises during the ventricular systole and then recoil when the pressure stops during ventricular diastole. If vessels were to harden and lose the ability to stretch and recoil, resistance to blood flow would be much greater.` |
front 20 Elastic arteries- | back 20 - The largest - Contains the highest proportion of elastic connective tissue |
front 21 Muscular arteries- | back 21 - Medium sized arteries - Have a greater proportion of smooth muscle than the other arteries |
front 22 Arterioles- | back 22 - Smallest of the three - Have all three tunics |
front 23 Which arteries are most directly responsible for controlling the amount of blood entering individual capillary beds? | back 23 Arterioles |
front 24 Autoregulation | back 24 Occurs through mechanisms that are activated in response to changes in local tissue demands 2 categories: metabolic and myogenic responses |
front 25 Metabolic respones | back 25 - Adjust blood flow based on the specific demands of local tissue Ex: endothelial cells of tunica intima produce and release strong vasodilators and vasoconstrictors. NO and endothelins are constantly produced and released; metabolic demands occur by adjusting the balance between the two mediators. |
front 26 Myogenic responses | back 26 - Occur reflexively within the smooth muscle of the tunica media - Prevents over or under delivery of blood to the tissues Ex: stretch, associated with increased pressure, causes vascular smooth muscle to contract, while decreased pressure and stretch causes it to relax. Arterioles avoid large changes to their diameter as systemic blood pressure fluctuates |
front 27 Elastic arteries | back 27 These arteries are closest to the heart and have relatively larger lumens than other arteries |
front 28 Muscular arteries | back 28 These arteries have the thickest tunica media of any vessel type |
front 29 Arterioles | back 29 These arteries can be so small that their wall is only an endothelium and a thin layer of smooth muscle fibers |
front 30 What would be the effect of capillaries with diameters less than 5 micrometers? | back 30 The capillaries would quickly plug with red blood cells, making them ineffective in delivering nutrients to tissues. |
front 31 Only the tunica intima is present in ___ - Tunica media and tunica externa are absent | back 31 Capillaries |
front 32 Capillaries have ___ ___ that make them even more permeable, facilitating the movement of fluid and small solutes between the blood and interstitial fluid | back 32 Intercellular clefts |
front 33 Continuous capillaries | back 33 - The most common and widely distributed type of capillary - Completeness of their endothelial lining - Do not contain pores, have tight junctions - Have pinocytotic vesicles that increase the permeability of continuous capillaries by allowing the movement of fluid and solutes across the capillary wall through endothelial cells - Specialized to be less permeable |
front 34 Fenestrated capillaries | back 34 - Endothelial cells are dotted with pores, or fenestrations that more readily allow the passage of fluid and larger molecules - More permeable - Fenestrations - Small intestine, kidney glomeruli, certain endocrine organs |
front 35 Sinusoid capillaries | back 35 - Permeability exceeds that of the fenestrated type - Serve bone marrow, spleen, and liver - Large fenestrations and a discontinuous basement membrane - Tight junctions are more incomplete, creating larger intercellular clefts |
front 36 Arrange the capillary tubes in order from the most to least permeable | back 36 - Sinusoid capillaries - Fenestrated capillaries - Continuous capillaries |
front 37 Portal system | back 37 An arrangement of vessels through which blood collected from one set of capillaries passes through a large vessel (or vein) to a second set of capillaries before returning to the systemic circulation and passing through the heart |
front 38 GI tract to liver- portal system | back 38 Capillary blood from GI tract passes through the hepatic portal vessel vein to a second capillary bed in the liver - Portal blood flow allows the liver to immediately monitor, detoxify, and adjust the materials absorbed in the intestine prior to release into the general venous circulation |
front 39 Hypothalamus to the anterior pituitary- portal system | back 39 Hypothalamaic neurons secrete releasing hormones into a capillary bed of the infundibulum that drains into a portal vessel that carries this blood to the anterior pituitary, which itself is drained by a second capillary bed into the general systemic circulation - Provides intimate and specific chemical signaling between these two important homeostatic regulatory structures |
front 40 Glomerulus capillary bed with the nephron of a kidney to the peritubular/vasa recta capillary beds also within the kidney- portal system | back 40 Blood is filtered by a capillary bed inside the glomerulus and then the same blood passes through the peritubular/vasa recta capillary bed surrounding nephrons |
front 41 Maternal placenta capillaries to the capillaries of the developing fetus-portal system | back 41 Maternal placental capillaries exchange nutrients with blood that then passes through fetal capillaries |
front 42 How does the presence of large fenestrations within sinusoids affect the movement of cancerous cells or bacteria? | back 42 It makes the movement of bacteria or cancer cells easier throughout the body. This is one of the drawbacks of this type of arrangement. |
front 43 Continuous capillary location | back 43 Skin |
front 44 Fenestrated capillary location | back 44 Small intestine |
front 45 Sinusoid capillary location | back 45 Bone marrow |
front 46 Capillaries are typically organized as branching networks of vessels called ___ ___ | back 46 Capillary beds |
front 47 Arterial capillaries | back 47 True capillaries arising from the metarterioles |
front 48 Venous capillaries | back 48 True capillaries emptying into the thoroughfare channel |
front 49 Microcirculation | back 49 Flow of blood from a terminal arteriole to a postcapillary venule through the capillary bed, is regulated by the precapillary sphincters in response to nervous input and local metabolic demands |
front 50 Which feature of the capillary wall results from incomplete tight junctions? | back 50 Intercellular clefts |
front 51 Venules | back 51 The smallest of the vessels carrying blood back toward the heart after it has passed through capillary networks - Have very thin walls; walls of postcapillary venules are thin enough to allow passage of fluids and to readily permit the movement of leukocytes by diapedesis |
front 52 Venules converge to form larger vessels called ___ | back 52 Veins - They have larger lumens and thinner walls than are arteries |
front 53 Thickest layer of a vein is ___ | back 53 Tunica externa |
front 54 Veins can be though of as ___ ___ and are often called ___ ___ | back 54 Blood reservoirs; capacitance vessels |
front 55 Which vessel types may be porous enough to allow diapedesis? | back 55 Capillaries and venules - Capillaries are the most permeable type of blood vessel. Postcapillary venules have walls that are thin enough to allow diapedesis. |
front 56 Venous valves | back 56 Ensure a undirectional flow of blood |
front 57 What would be the impact on venous physiology if the tunica media had many smooth muscle cell layers? | back 57 You would lose venous compliance and the ability of the veins to store extra blood. This would increase the amount of blood within the arterial side of the circulatory system, and hence blood pressure. |
front 58 Varicose veins | back 58 Result from failure of the venous valves, which allows blood to back-up and pool in the peripheral veins of the legs |
front 59 Explain the function of venous valves | back 59 In veins, valves ensure that blood flow is unidirectional despite being under low pressure |
front 60 Are the effects of gravity the same in the body when a person is swimming compared with standing or with lying down? | back 60 No, when swimming, people are at neutral buoyancy, minimizing the effects of gravity |
front 61 What is the likely problem the patient is suffering from (lips blue, no pulse in right leg, hairdresser)? | back 61 Deep vein thrombosis |
front 62 Anastosomes | back 62 Specialized connections between blood vessels that permit alternate routes of blood flow |
front 63 Arterial anastosomes create ___ ___ that provide multiple, additional pathways for blood delivery | back 63 Collateral channels |
front 64 Arteriovenous anastosomes | back 64 Direct connections between arterioles and venules, which are primarily controlled by the sympathetic nervous system |
front 65 Blood flow (F) | back 65 The volume of blood per unit of time moving through a vessel, tissue, organ, or the entire circulation, F is the same as cardiac output (CO), which is the amount of blood pumped by either ventricle each minute - Blood flow between two points in the circulation is directly proportional to the difference in pressure |
front 66 Blood pressure (BP) | back 66 - Form of hydrostatic pressure - Is the force exerted onto a given area of the vessel wall by the blood contained within the vessel, and is measured in mmHG |
front 67 Resistance (R) | back 67 Friction encountered by blood that impedes its flow |
front 68 Briefly describe the relationship between blood flow, blood pressure, and resistance using the formula discussed. What is the relationship between flow and pressure? What is the relationship between flow and resistance? | back 68 Flow (F) varies directly with the difference in pressure (delta P) and inversely with resistance (R). As delta P increases, F increases; as R increases, F decreases. |
front 69 If the viscosity (thickness) of a fluid moving through a tube were to decrease, what would happen to the value of delta P? | back 69 Delta P would decrease |
front 70 Peripheral resistance is ___ | back 70 - Directly proportional to blood vessel length - Directly proportional to blood viscosity |
front 71 Total peripheral resistance | back 71 Used to describe the forces impeding blood flow through the systemic circulation |
front 72 Laminar flow | back 72 Under normal conditions, with a constant blood vessel diameter, blood flows with laminar flow - Blood moving within different sections of a vessel's cross-sectional diameter moves witht he same relative velocity |
front 73 Turbulent flow | back 73 Abrupt change to the diameter of the vessel disrupts this continuity and causes turbulent flow - Blood will flow at varying relative velocities in different sections of the vessel, thereby increasing resistance |