Term
| What are the three major types of blood vessels? |
|
Definition
| arteries, capillaries, and veins |
|
|
Term
| Arteries carry blood ______ _____ the heart? |
|
Definition
|
|
Term
| Veins carry blood _____ _____ heart? |
|
Definition
|
|
Term
| What are the three tunics of arteries and veins? |
|
Definition
|
|
Term
| What are capillaries composed of? |
|
Definition
| endothelium with sparse basal lamina |
|
|
Term
| Where is the tunica interna located? |
|
Definition
| lines the lumen of all vessels |
|
|
Term
| If the vessel is larger than 1mm, what else is present in the tunica interna? |
|
Definition
| a subendothelial connective tissue basement membrane |
|
|
Term
| Which vessel has a thicker tunica media? |
|
Definition
|
|
Term
| What is the tunica media's composition? |
|
Definition
| smooth muscle and elastic fiber layer |
|
|
Term
| How is the tunica media regulated by? |
|
Definition
| sympathetic nervous system |
|
|
Term
| What is the role of the tunica media? |
|
Definition
| controls vasoconstriction, vasodilaiton of vessels |
|
|
Term
| When is vasoconstriction/vasodilation of vessels needed? |
|
Definition
| heat regulation, food, oxygen need |
|
|
Term
| What is the tunica externa composed of? |
|
Definition
| collage fibers that protect and reinforce vessels |
|
|
Term
| What do larger vessels contain by the tunica externa? |
|
Definition
|
|
Term
| How are the tunica interna and the tunica media fed? |
|
Definition
|
|
Term
| How is the tunica externa fed? |
|
Definition
|
|
Term
|
Definition
| network of arterioles, capillares and vessels provide vessel wall with metabolites |
|
|
Term
| What is common between the elastic (conducting arteries)? |
|
Definition
| thick-walled, near the heart |
|
|
Term
| What are the elastic (conducting) arteries? |
|
Definition
| aorta and its major branches |
|
|
Term
| What are characteristics of conducting arteries? |
|
Definition
| large lumen, elastin in all 3 tunics |
|
|
Term
| What are functions of the conducting arteries? |
|
Definition
| low-resistance conduction of blood, with and smooth out large bp fluctuations, pressure reservoirs |
|
|
Term
| What is common between the muscular (distributing arteries)? |
|
Definition
| distal to elastic arteries; deliver blood to body organs |
|
|
Term
| What are the characteristics of muscular arteries? |
|
Definition
| thick tunica media with more smooth muscle |
|
|
Term
| Function of muscular arteries |
|
Definition
| active in vasoconstriction |
|
|
Term
| Characteristics of arterioles? |
|
Definition
| smallest arteries, lead to capillary beds, control flow into capillary beds via vasodilation and constriction |
|
|
Term
| How thick are capillaries? |
|
Definition
| walls consist of a thin tunica interna, one cell thick |
|
|
Term
| What stabilies the outerwalls of capillaries? |
|
Definition
|
|
Term
| What are the three types of capillaries? |
|
Definition
| continuous, fenestrated, and sinusoids |
|
|
Term
| Where are continuous capillaries abundant? |
|
Definition
|
|
Term
| Characteristics of a continuous capillary? |
|
Definition
| uninterrupted lining, adjacent cells are connected with tight junctions, intercellular clefts allow passage of fluids |
|
|
Term
| Where are fenestrated capillaries found? |
|
Definition
| wherever active capillary absorption or filtrate formation occurs (small intestines, endocrine glands, kidneys) |
|
|
Term
| Where are sinusoid capillaries found? |
|
Definition
| liver, bone marrow, lymphoid tissue, some endocrine organs |
|
|
Term
| What are the characteristics of a sinusoid capillary? |
|
Definition
| leaky, fenestrated, with large lumens |
|
|
Term
|
Definition
| allow large molecuels (proteins and blood cells) to pass between the blood and surrounding tissue |
|
|
Term
|
Definition
| microcirculation of interwoven metwrosk of capillaries |
|
|
Term
| What do capillary beds consist of? |
|
Definition
| vascular shunts and true capillaries |
|
|
Term
| What is a vascular shunt? |
|
Definition
| metarteriole-thoroughfare channel. connects an ateriole directly with a postcapillary venule |
|
|
Term
| What is a true capillary? |
|
Definition
| 10-100 per capillary bed, branch of the metarteriole and return to the thoroughfare channel at the distal end |
|
|
Term
| What is the precapillary sphincter? |
|
Definition
| cuff of smooth muslce that surrounds each true capillary |
|
|
Term
| What is the role of the precapillary sphincter? |
|
Definition
| regulate blood flow into the capillary |
|
|
Term
| How is blood flow through capillary beds regulated? |
|
Definition
| vasomotor nerves and local chemical conditions |
|
|
Term
| What are the parts of the venous system? |
|
Definition
|
|
Term
|
Definition
| when capillary beds unite |
|
|
Term
| What are postcapillary venules? |
|
Definition
| smallest venules, composed of endothelium and a few pericytes |
|
|
Term
| How are large venules different? |
|
Definition
| one ore two layers of smooth msucle (tunica media) |
|
|
Term
|
Definition
|
|
Term
| What is different about the tunica media of veins? |
|
Definition
|
|
Term
| What is different abut the tunica externa of veins? |
|
Definition
| thick, consisting of collagen fibers and elastic networks |
|
|
Term
| What is the role of veins? |
|
Definition
| capactiance vessels (blood reservoirs) contain 65% of blood supply |
|
|
Term
| Which has lower blood pressure arteries or veins? |
|
Definition
|
|
Term
| Which has thinner walls? Arteries or veins? |
|
Definition
|
|
Term
| What special adaptations do veins possess to return blood to the heart? |
|
Definition
| Large-diameter lumens, valves |
|
|
Term
| What do the large-diameter lumens of veins allow? |
|
Definition
| little resistance to blood flow |
|
|
Term
| What do the valves of the veins resemble? |
|
Definition
|
|
Term
| What is the role of valves in veins? |
|
Definition
| prevent backflow of blood |
|
|
Term
|
Definition
|
|
Term
|
Definition
| blood flow considering the entire vascular system |
|
|
Term
| What is blood flow/cardiac output? |
|
Definition
| Actual volume of blood flowing through a vessel, organ, or the entire circulation in a given period |
|
|
Term
| How is blood flow measured? |
|
Definition
|
|
Term
| How varied is the blood flow between individual organs? |
|
Definition
|
|
Term
|
Definition
| force per unit area exerted on the wall of a blood vessels by its ocntained blood |
|
|
Term
| How is blood pressure expressed? |
|
Definition
|
|
Term
|
Definition
| reference to system arterial BP in large arteries near the heart |
|
|
Term
| What do the differences in BP within the vascular system provide? |
|
Definition
| Driving force that keeps blood moving from high to low pressure areas |
|
|
Term
| What are the three important of sources of blood resistance? |
|
Definition
| blood viscosity, total blood vessel length, and blood vessel diameter |
|
|
Term
| What are the resistance factors that remain releatively constant? |
|
Definition
| viscosity, blood vessel length |
|
|
Term
| What causes an increase in blood vessel length? |
|
Definition
| increase in body volume such as pregnancy or obesity |
|
|
Term
| How often are there changes in blood vessel diameter? |
|
Definition
| frequent and significantly alter peripheral resistance |
|
|
Term
| What is the relationship between resistance and blood vessel radius? |
|
Definition
| resistance = 1/(change in) radius^4. so doubling the radius, makes 1/16 of original resistance |
|
|
Term
| What are the major determinants of peripheral resistance? |
|
Definition
| small-diameter arterioles, fatty plaques from atherosclerosis |
|
|
Term
| What changes occur to blood flow as a result of fatty plaques? |
|
Definition
| turbulent blood flow dramatically increases resistance |
|
|
Term
| As resistance _____ and blood flow ______ BP ________ |
|
Definition
| increases, decreases, increases |
|
|
Term
| Which has a greater influence on changing blood pressure, resistance or flow? |
|
Definition
|
|
Term
| Where is systemic pressure highest? |
|
Definition
|
|
Term
| What happens to systemic pressure after leaving the aorta? |
|
Definition
| declines throughout the length of the pathway |
|
|
Term
| What is the BP measure in the right atrium? |
|
Definition
|
|
Term
| WHere does the steepest change in bp occur? |
|
Definition
|
|
Term
| Why is there such a steep change in bp in the arterioles? |
|
Definition
| so the capillaries are not blown out |
|
|
Term
| Where is capillary pressure higher in the body? |
|
Definition
|
|
Term
| What two factors does arterial bp reflect? |
|
Definition
| elasticity, amount of blood forced into them at any given time |
|
|
Term
| What is systolic pressure? |
|
Definition
| pressure exerted on arterial walls during ventricular contraction |
|
|
Term
| What is diastolic pressure? |
|
Definition
| lowest level of arterial pressure during a ventricular cycle |
|
|
Term
|
Definition
| difference between systolic and diastolic pressure |
|
|
Term
| What are the capillary BP ranges? |
|
Definition
|
|
Term
| How much does venous BP fluctuate? |
|
Definition
| it is steady and changes little during cardiac cycle |
|
|
Term
| What is the pressure gradient in the venous system? |
|
Definition
|
|
Term
| What does blood flow from a cut vein look like? |
|
Definition
|
|
Term
| What does blood flow from a lacerated artery look like? |
|
Definition
|
|
Term
| Is venous bp enough to promote adequate blood return to the heart? |
|
Definition
|
|
Term
| What aids venous BP in adequate blood return? |
|
Definition
| respiratory "pump", muscular "pump" |
|
|
Term
| What is the respiratory "pump"? |
|
Definition
| pressure changes created during breathing, drawing blood toward the heart by squeezing local veins |
|
|
Term
| What is the muscular "pump"? |
|
Definition
| contraction of skeletal muscles "milk" blood toward heart |
|
|
Term
| What else aids in venous bp blood return? |
|
Definition
| Valves to prevent backflow |
|
|
Term
| What does the maintenance of blood pressure require? |
|
Definition
| cooperation of heart, blood vessels, and kidneys, supervision of the brain |
|
|
Term
| What are teh main factors influencing blood pressure? |
|
Definition
| cardiac output, peripheral resistance, blood volume |
|
|
Term
| What effect does cardiac output have on blood pressure? |
|
Definition
|
|
Term
| What effect does peripheral resistance have on BP? |
|
Definition
| higher viscosity, increased blood vessel length, and blockages increase BP the most |
|
|
Term
| Which factors of peripheral resistance have the greatest effect on increasing blood pressure? |
|
Definition
| blood vessel length and blockages |
|
|
Term
| Cardiac Output x Peripheral Resistance = ? |
|
Definition
|
|
Term
| Difference between arteries and veins: Artery Delivery |
|
Definition
| blood pumped into single systemic artery - the aorta |
|
|
Term
| Difference between arteries and veins: Artery Location |
|
Definition
| deep, and protected by tissue |
|
|
Term
| Difference between arteries and veins: Artery Pathways |
|
Definition
|
|
Term
| Difference between arteries and veins: Artery Supply/Drainage |
|
Definition
|
|
Term
| Difference between arteries and veins: Artery Supply/Drainage |
|
Definition
|
|
Term
| Difference between arteries and veins: Veins Delivery |
|
Definition
| blood returns via superior and inferior venae cave and the coronary sinus |
|
|
Term
| Difference between arteries and veins: Veins Location |
|
Definition
| both deep and superficial |
|
|
Term
| Difference between arteries and veins: Veins Pathways |
|
Definition
| convergent interconnections |
|
|
Term
| Difference between arteries and veins: Veins supply/drainage |
|
Definition
| dural sinuses and hepatic portal circulation |
|
|
