The Cardiovascular System: Blood Vessels
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| blood vessels | form a closed delivery system that begins & ends @ the heart
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| 3 major types of blood vessels are | arteries, capillaries & veins
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| arterioles | smallest branches in the arteries that feed into the capillary beds of body organs & tissues. regulate blood flow into capillary beds by vasoconstriction or vasodilation.
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| venules | where blood draining from the capillaries flows
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| artieries & veins act as ____ for blood | conduits
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| arteries carry blood ______ the heart | away from
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| arteries carry blood that is _________in oxygen | high
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| veins cary blood _______ the heart | toward
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| veins carry blood that is _________in oxygen | low
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| exchanges between blood & tissue cells occur through | gossamer-thin capillary walls
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| wall of all blood vessels are composed of | 3 distinct layers (tunics)
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| vessel lumen | a central blood-containing space that is surrounded by tunics
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| innermost tunic is the | tunica interna/ tunica intima; in intimate contact with the blood in the lumen; contains the endothelium
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| endothelium | simple squamous epithelium lines the lumen of all vessels, continuation of the endocardial lining of the heart, forms a slick surface that minimizes friction as blood moves through the vessel lumen
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| subendothelial layer | present in vessels larger than 1mm in diameter; loose connective tissue (basement membrane) supports the endothelium
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| tunica media | middle tunic, circularly arranged smoth muscle cells & sheets of elastin; critical in regulating circulatory dynamics (bulkiest layer in arteries, cheif resp. for maintaining bp & continuous blood circ)
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| vasomotor nerve fibers | regulates the activity of the smooth muscle; present in the sympathetic division of the autonomic nervous sytem & a whole battery of chemicals
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| vasoconstriction | reduction in lumen diameter due to smooth muscle contraction
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| vasodilation | widening of the lumen due to smooth muscle relaxation
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| tunica externa | tunica adventitia (outermost layer of blood vessel wall) composed of loosely woven collagen fibers, filled w/ nerve fibers & lymphatic vesels; in lg veins (its a network of elastin fibers)
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| why do tunica externa have collagen fibers? | portects & reinforces the blood vessel & it anchors it to surrounding structures
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| vasa vasorum | "vessels of the vessels" (present in larger vessels; its a system of tiny blood vessels); nurishes the more external tissues of the blood vessel wall
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| arteries | vessels that transport blood away from the heart
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| systemic arteries | carry oxygenated blood
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| systemic veins | carry oxygen-poor blood
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| 3 groups of arteries | elastic, muscular & arterioles
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| elastic artieries | (conducting arteries) thick-walled arteires near the heart--the aorta & it's maajor branches, have a large lumen contain substantial amounts of smooth muscle
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| why are elastic arteries known as conducting arteries? | b.c their large lumen allows them to serve as low-resistance pathways that conduct blood for the heart to medim0sized arteries
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| where are elastic arteries seen most in? | tunica media
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| how is their reaction in vasoconstriction | they are relativly inactive, even though the contain substantial amounts of smooth muscle
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| arteriosclerosis | (narrowing of arteries) when blood vessels become hard & unyielding, causes blod to flow more intermittently
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| muscular arteries | (distributing arteries); deliver blood to specific body organs & account for most of the named arteries studied (have thickest media of all vessels); more active in vasoconstriction & less distensible
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| what is present on the face of the tunica media in muscular arteries | elastic lamina
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| arterioles | smallest of the arteries; have chiefly smooth muscle with few scattered elastic fibers
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| the smaller arterioles lead into the | capillary beds
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| fibrous or atherosclerotic plaques | production of fibrous lesions w/ a core of dead & dying foam cells
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| capillaries | smallest blood vessels
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| what are in their walls? | thin tunica interna
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| pericytes | smooth muscle-like cells that stabilize the capillary wall
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| what are poorly vascularized by capillaries? | tendons & ligaments
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| what lack capillaries andy how do they receive nutrients | cartilage & epithelia lack apillaries, receive nutrients from blood vessels in nearby connective tissues & the avascular cornea & lens of the eye receive nutrients from the aqueous humor
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| capillaries role is to | exchange materials (gases, nutrients, hormones between blood & interstitial fluid
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| name they types of capillaries | continuous, fenestrated, & sinusoidal
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| continuous capillaries | abundant in skin & muscles;
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| intercellular clefts | incomplete, gaps of unjoined membrane caused by adjacent cells of continuous capillaries; thay are large enough to allow limited passage of fluids & small solutes
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| fenestrated capillaries | similar to continuous except their endothelial cells are riddled with oval pores, or fenestrations (fenestra=window)
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| what covers fenestrations | delicate membrane, or diaphram
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| where are fenestrated capillaries found | where active capillary absorption or filtrate formation occurs (ex. in sm. intes. receive digested food nutrients & those in eno organs allow hormones rapid entry into the blood (FC- w/ perpetually open ores occur in the kidneys where rapid filtration of
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| sinusoids | sinusoidal capillaries;leaky capillaries found only in certain organs (liver, bone marrow, lymphoid tissues & some endocrine organs); large irreularly shaped lumens are usually fenestrated
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| in the liver endothelium of the sinusoids is ____ | discontinuous
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| Kupffer cells | large macrophages that form part of the lining in the endothelium part of the liver of the sinusoids
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| capillary bed | interweaving network formed by capillaries
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| microcirculation | flow of blood from an arteriole to a venule (capillary bed)
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| a capillary bed consists of 2 types of vessels | (1) vascular shunt (metarteriole-thoroughfare channel) (2) true capillaries, he actual excchange vessels
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| what is a vascular shunt? | a short vessel that directly connects the arteriole & venule @ opposite ends of the bed
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| the ___ feeding the bed leads into a _____ which is directly continuous w/ the _____ | terminal arteriole; metarterile; thoroughfare channel
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| what is a metarteriole | a vessel structurally intermediate between an arteriole & a capillary
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| what is a thoroughfare channel | intermediate between a capillary & a venule
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| the thoroughfare channel, in turn, joins the ___ that drains the bed | postcapillary venule
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| true capillaries | branch off the metarteriole (proximal end of the shunt) & return to the thoroughfare channel (distal end), but can sometimes spring from terminal arteriole & empty directly into the venule
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| precapillary sphincter | cuff of smooth muscle fibers; surrounds the root of each true capillary @ the metarteriole & acts as a valve to regulate the flow of blood into the capillary
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| blood flowing through a terminal arteriole may take what routes | either through the true capillaries or through the shunt
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| venules | formed when capillaries unite
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| postcapillary venules | smallest venules, consist entirely of endothelium around which a few pericytes congregate
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| veins | form when venules join
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| capacitance | (blood reservoirs) refers to veins b.c. up to 65% of the body's total blood supply is found there
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| venous valves | formed from folds of the tunica interna, the resemble the semilunar valves of the heart in both structure & function
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| varicose veins | veins that have become tortuous & dilated b.c of incompetent vlaves
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| hemorrhoids | resulting variocosites in the anal veins
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| venous sinuses | (coronary sinus of the heart & dural sinuses of the brain are highly specialized, flattened veins w extremely thin walls composed only of endothelim)
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| vascular anastomes | where vascular channels unite
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| arterial anastomses | when arteries supplying the same territory often merge bc most organs receive blodd from more than one arterial branch
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| collateral channels | the alternate pathways provided by arterial anastomoses
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| arteriovenous anastomoses | the metarteriloe--thoroughfare channel shunts of capillary beds that connect arterioles & venules
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| blood flow | actual volum of blood flowing through a vessel, an organ, or the entire circulation in a given period (ml/min)
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| BP | force per unit area exerted on teh wall of a blood vessel by its contained blood
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| resistance | opposition to flow & is a measure of the amount of friction blood encounters as it passes through the vessels (peripheral resistance(PR))
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| blood viscosity | internal resistance to flow & is related to the thickness or "stickiness" of a fluid
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| Total blood vessel length | relationship between total blood cessel length & resistance; longer total vessel length, greater resistance encountered
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| blood vessel diameter | fluid close to the walls of a tube or channel is slowed by friction as it passes along the wll, whereas fluid in the center of the channel flows more freely & faster
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| systolic pressure | when the L ventricle contracts & expels blood into the aorta, it imparts kinetic energy to the blood, which in turn stretches the elastic aorta as aortic pressure reaches its peak (*pressure peak)
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| diastolic pressure | aortic pressure drops to its lowest level (approx. 70 80 mm Hg)
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| pulse pressure | differenece between systolic & diastolic pressures (throbbing pulsation in an artery during systole)
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| MAP | mean arterial pressure; propels the blood to the tissues throughout the cardiac cycle
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| respiratory pump | sucks blood upward toward the heart, as we inhale, abdominal pressure increases; caused by pressure changes occurring in ventral body cavity during breathing
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| muscular pump | skeletal muscle activity; it milks bolood toward the heart, & once blood passes each successive valve, it cannot flow back; this is bc the skeletal muscles surounding the deep veins contract & relax
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| vasomotor center | neural center that oversees changes in the diameter of blood vessels; a cluster of sympathetic neurons in the medulla
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| cardiovascular center | integrates bp control by altering cardiac output & blood vessel diameter
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| vasomotor fibers | sympathetic efferents (motor fibers) where the vasomotor center transmits impulses at a fairly steady rate along; the exit fm the T1 through L2 levels of the spinal cord & run to innervated the smooth muscle of blood vessels, most import arterioles
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| vasomotor tone | a state of moderate constriction
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| carotid sinus reflex | protects the blood supply to the brain
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| aortic reflex | concerned with maintaining adequate bp in the systemic circuit as a whole
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| changing levels of oxygen & carbon dioxide help regulate bp via the ____ | chemoreceptor reflexes
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| adrenal medulla hormones are | norepinephrine (NE) & epinephrine; released during periods of stress
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| what does NE & E do? | enhances the sypathetic fight-or-flight response (increase BP)
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| more specifically what does NE do? | has a vasoconstrictive action
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| what does epinephrine do | increases cardiac output & promotes generalized vasoconstriction (except in skeletal & cardiac muscle, where it generally causes vasodilation)
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| what effects does nicotine have | mimics the effects of catecholamines, causes intense vasoconstriction not only by direct stimulating ganglionic sympathetic neurons but also by prompting release of lg amounts of E & NE
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| ANP | atrial natriuretic peptide; a peptide hormone produced by the atria of the heart that causes blood volume & BP to decline; antagonizes aldosterone & prods the kidneys to excrete more sodium & h2o fm the body, causing blood volume to drop; also causes gen
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| ADH | (antidiuretic hormone) produced by hypothalamus & stimulates the kidneys to conserve water, when BP falls to dangerously low levels (sever hemorhage) muchmore ADH is released & helps to restore arterial pressure by causing intense vasoconstriction
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| angiotensin II | generated in response to renin released by the kidneys when renal perfusion is inadequate; causes intense vascoconstriction, promoting rapid rise in systemic bp; also stimulates rlease of aldosterone & ADH which act in long-term regulation of bp by enhanc
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| endothelium | source of several chemicals that affect vascular smooth muscle (as well as blood clotting) ex. peptide endothelin is one of most potent vasocon., released in response to low blood flow, it appears to bring about long-lasting effects by enhancing calcium e
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| PDGF | also relased by endothelia cells (prostaglandin-derived growth factor), another vasocons chem.
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| NO | nitric oxide; called endotheliumdervied relaxing factor; is released in direct response to a high blood flow & signaling molecules such as acetylcholine & bradykinin (& the vasodilator nitroglycerine) & its released is a 2ndary or consequent response to t
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| NO acts via a | cyclic GMP 2nd messenger system, promotes both reflex (systemic) & highly localized vasodilaion
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| NO is quickly | destroyed
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| histamne, prostacyclin, kinins, & certain chemicals are released during | inflammatory response & certain allergic responses are potent vasodilatores; promote fluid loss fm bloodstream by increasing cappillary permeability
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| alcohol causes | bp to drop by inhibiting ADH release, by depressing the vasomotor center, & by promoting vasodilation, esp. in skin (accounts for flushed app. of someone who has drunk a gen am of alc
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| renin-angiotensin mechanism | involves indirect renal mech.
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| when arterial bp declines, special cells inthe kidneys release the enzyme____ | renin into the blood
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| renin triggers a series of enzymatic reactions that produce ____ | angiotensin II (potent vasoconstrictor, promoting an increase in bp, increases rate of blood delivery to the kidneys & renal perfusion
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| aldosterone | hormone that enhances renal reabsorption of sodum, & prods the post pit release DH (promotes more water reabsorption (stimulated by the adrenal cortex)
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| pressure points | points that are compressed to stop blood flow into distal tissues during hemorrhage (ex seriously lacerate your hand, you can slow or stop the bleeding by compressing the radial or brachial artery)
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| hypotension | low blood pressure (systolic bp below 100 mm Hg
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| orhostatic hypotension | temporary low bp & dizziness when they rise sudenly fm reclining or sitting position
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| chronic hypotension | hints poor nutrition, bc poorly nourished are often anemic & have inadequate levels of blood proteins
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| hyper tension | high bp (common in obese people bc the total length of their blod vessels is relatively greater than that in thinner individuals
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| about 90% of hypertensie people have___ or ___ ___ in which no underlying cause has been identified | primary, or essential, hypertension
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| secondary hypertension | accounts for 10% of cases, due to indentifiable disorders such as excessive renin secretion by the kidneys, arteriosclerosis, & endocrine disorders such as hyperthyroidism & Cusching's disease
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| tissue perfusion | blood flow through body tissues involved (1) delivery ofoxygen & nutrients to & removal of wastes f tissue cells (2) exchange in the lungs (3) absorption of nutrients fm diges trach & (4) urine formation by the kidneys
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| autoregulation | automatic adjustment of blood flow to each tissue in proportion to its requirements at any point in time
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| myogenic responses | (blank)
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| reactive hyperemia | dramatic increae in blood flow into a tissue thatoccurs after the blood supply to an area has been temp blocked
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| active/exercised hyperemia | phenomenon whenmuscles become active, blood flow increases (hyperemia) in direct proportion to their greater metabolic activity
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| vasomotion | reflects the on/off opening & closing of precapillary sphincters in response to local autoregulatory controls
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| diffusion | when O, CO & nutrients & metabolic wastes pass between the blood & interstitial fluid via ___
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| capillary hydrostatic pressure (HPc) | tends to force fluids through the capillary walls
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| interstitial fluid hydrostatic pressure (HPif) | opposes the bp which forces fluid out of the capillaries acting outside the capillaries (back pressure) pushing fluid in
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| capillary colloid osmotic pressure (OPc) | (oncotic pressure); developed by the abundant plasma proteins in capillary blood (primarily albuminmolecues) approx 26 m Hg
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| net filtrationpressure (NFP) | determine whether there is a net gain or net loss of fluid fm the blood; considers all of the forces acting at the capillary bed
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| circulatory shock | any condition in which blood vessels are inadequately filled & blood coannot circulate normally
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| hypovolemic shock | results from large-scale loss of blood, as might follow acute hemorrhage, sever vomiting or diarrhea or extensive burns
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| cardiogenic shock | pump failure, occurs when the heart is so inefficient that it canot sustain adequate circulation
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| vascular system | used when referring to the body's complex network of bloos vessels
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| blood islands | the endothelial lining of blood vessels is formed by mesodermal cells, which collect in little masses
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| Blood is carried | in a closed system of vessels that begins and ends at the heart
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| The three major types of vessels are | arteries, capillaries, and veins
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| Arteries carry blood | away from the heart
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| veins carry blood | toward the heart
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| Capillaries contact | tissue cells
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| Capillaries directly serve | cellular needs
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| The three tunics that arteries and veins are composed of | tunica interna (intima), tunica media, and tunica externa
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| central blood-containing space surrounded by tunics | Lumen
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| the tunica intima | reduces friction between the blood and the blood vessels
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| the tunica media | controls vasoconstriction and vasodilation
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| the tunica externa ________, _______ & ______the blood vessel to surrounding structures | protects, reinforces and anchors
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| Elastic or conducting arteries contain what? & what does this allow? | large amounts of elastin, which allows these vessels to withstand and smooth out the pressure fluctuation due to the pumping action of the heart.
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| Muscular or distributing arteries deliver blood to | specific body organs
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| What type of arteries have the most tunica media of all the vessels? | Muscular or distributing arteries.
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| These vessels are active in vasoconstriction | Muscular or distributing arteries
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| Arterioles | the smallest arteries
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| Arterioles regulate blood flow into capillary beds | vasoconstriction or vasodilation.
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| Capillaries | the smallest blood vessels
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| Capillaries allow for exchange of substances between | the blood and interstitial fluid
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| There are three structural types of capillaries | continuous, fenestrated, and sinusoids
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| Continuous capillaries | allow passage of fluids and small solutes
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| Most common type of capillaries | Continuous capilaries
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| Fenestrated capillaries | are more permeable to fluid and solutes than continuous capillaries
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| Fenestrated capillaries are found | wherever active capillary absorption or filtrate formation occurs (e.g., small intestines, endocrine glands, and kidneys)
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| Sinusoidal capillaries are | leaky capillaries with large lumens;
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| Sinusoidal capillaries allow | large molecules (proteins and blood cells) to pass between the blood and surrounding tissues
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| Where are Sinusoidal capillaries found? | in the liver, bone marrow, lymphoid tissue, and in some endocrine organs
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| How does Blood flow within Sinusoidal capillaries? | sluggishly, allowing for modification in various ways
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| Capillary Beds are | Microcirculatory networks
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| Capillary Beds consist of | 1.Vascular shunts 2.True capillaries
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| True capillaries | function as the exchange vessels
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| Vascular shunts | metarteriole-thoroughfare channel connecting an arteriole directly with a postcapillary venule
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| precapillary sphincter | A cuff of smooth muscle that surround each capillary at the matearteriole and acts as to regulate blood flow into the capillary
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| Venules and Veins are found in what system? | Venous System
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| Where are Venules formed? | where capillaries converge
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| Venules allow | fluid and white blood cells to move easily between the blood and tissues
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| When venules converge what are formed? | Veins are formed
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| Veins are formed | when venules converge
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| Veins | are relatively thin walled with large lumens
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| Veins contain about ¬¬¬¬¬____% of the blood supply | 65%
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| Veins have much _________blood pressure and _______walls than arteries | lower, thinner
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| To return blood to the heart, veins have special adaptations What are they and describe each | 1.Large-diameter lumens, which offer little resistance to flow 2.Valves (resembling semilunar heart valves), which prevent backflow of blood
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| Vascular Anastomoses | Merging blood vessels, more common in veins than arteries
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| Arterial anastomoses provide | alternate pathways (collateral channels) for blood to reach a given body region
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| If one branch is blocked (regarding Arterial anastomoses) | the collateral channel can supply the area with adequate blood supply
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| Blood Flow | Actual volume of blood flowing through a vessel, an organ, or the entire circulation in a given period:
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| Blood Flow is measured in | ml per min.
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| Blood Flow is relatively | constant when at rest
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| Blood Pressure (BP) | Force per unit area exerted on the wall of a blood vessel by its contained blood
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| Blood Pressure (BP) is Expressed in | millimeters of mercury (mm Hg)
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| What is the "opposition to flow"? | Resistance
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| Resistance | Measure of the friction between blood and the vessel walls
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| Resistance comes from 3 sources | blood viscosity, total blood vessel length, blood vessel diameter
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| If Blood Pressure increases, blood flow _________ | increases
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| if BP decreases | blood flow_______
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| If resistance increases, blood flow¬¬¬¬¬________ | decreases
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| Peripheral resistance is | the most important factor influencing local blood flow
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| vasoconstriction (or vasodilation) can dramatically | alter local blood flow, while the BP remains unchanged
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| Systemic Blood Pressure | The pumping action of the heart generates blood flow (through the vessels along a pressure gradient, always moving from higher- to lower-pressure areas)
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| Systemic Blood Pressure results when | flow is opposed by resistance
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| Three things about Systemic pressure | Is highest in the aorta, Declines throughout the length of the pathway, Is 0 mm Hg in the right atrium
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| Arterial BP reflects two factors of the arteries close to the heart | 1.Their elasticity (compliance or distensibility) 2.The amount of blood forced into them at any given time
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| Arterial Blood Pressure occurs in | elastic arteries near the heart
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| Arterial BP is | pulsatile (BP rises and falls)
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| systolic pressure | When the left ventricle contracts, blood is forced into the aorta producing a peak in pressure (120 mm Hg)
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| Diastolic pressure | pressure that occurs when the blood can not flow back into the heart and the aorta recoils (the diameter is smaller) (70-80 mm Hg)
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| Pulse pressure | the difference between systolic and diastolic pressure
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| Mean arterial pressure (MAP) | pressure that propels the blood to the tissues
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| Is Capillary BP low or high? | low
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| Low capillary pressure is desirable because | high BP would rupture the fragile, thin-walled capillaries
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| low capillary BP is sufficient to | exchange between the blood and tissues
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| Venous BP | steady and changes little during the cardiac cycle
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| The pressure gradient in the venous system is | only about 20 mm Hg
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| A cut vein has ¬¬¬¬¬______blood flow; a lacerated artery flows | even; in spurts
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| Blood pressure varies directly with changes in (2 things) | blood volume and cardiac output
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| blood volume and cardiac output are determined mainly by (3 things) | venous return, neural and hormonal controls
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| What two ways are Short-Term Mechanisms controlled? | Neural Controls and chemical controls
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| Neural controls of peripheral resistance do two things | 1. Alter blood distribution to respond to specific demands 2. Maintain MAP by altering blood vessel diameter
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| The vasomotor center | a cluster of sympathetic nerons in the medulla that controls changes in the diameter of the blood vessels
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| Baroreceptors | detect stretch impulses to the vasomotor center, inhibits its activity and promotes vasodilation of arterioles and veins (Baroreceptor Reflexes)
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| Chemoreceptors | detect a rise in CO2 content of the blood and stimulate the cardioacceleratory and vasomotor centers increased cardiac output and vasoconstriction
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| The cortex and hypothalamus modify arterial pressure? | via the medullary centers
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| Blood pressure is regulated by | chemoreceptor reflexes sensitive to oxygen and carbon dioxide
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| Chemoreceptors sensitive to oxygen and carbon dioxide are found in the | carotid and aortic bodies
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| Reflexes that regulate blood pressure are integrated in the | medulla
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| Higher brain centers (cortex and hypothalamus) can modify BP via | relays to medullary centers
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| Chemicals that Increase Blood Pressure | Adrenal medulla hormones, Antidiuretic hormone (ADH), Angiotensin II, Endothelium-derived factors
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| Adrenal medulla hormones | norepinephrine and epinephrine increase blood pressure
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| Antidiuretic hormone (ADH) | causes intense vasoconstriction in cases of extremely low BP
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| Angiotensin II | kidney release of renin generates angiotensin II, which causes intense vasoconstriction
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| Endothelium-derived factors | promote vasoconstriction and are released in response to low blood flow
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| Chemicals that Decrease Blood Pressure | Atrial natriuretic peptide (ANP), Nitric oxide (NO), Inflammatory chemicals, Alcohol
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| Atrial natriuretic peptide (ANP) | causes blood volume and pressure to decline
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| Nitric oxide (NO) | has brief but potent vasodilator effects
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| Inflammatory chemicals | histamine, prostacyclin, and kinins are potent vasodilators
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| Alcohol | causes BP to drop by inhibiting ADH
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| 2 Long-Term Mechanisms (Renal Regulation) | Direct Mechanism and Indirect renal mechanism
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| Long-term mechanisms | control BP by altering blood volume
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| Increased BP (Direct Mechanism) | stimulates the kidneys to eliminate water, thus reducing blood volume dec in BP
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| Decreased BP (Direct Mechanism) | stimulates the kidneys to increase blood volume and BP
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| Indirect renal mechanism | involves the renin-angiotensin mechanism, a dec in BP systemic vasoconstriction
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| Efficiency of the circulation can be assessed by | taking pulse and blood pressure measurements
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| Vital signs | pulse and blood pressure, along with respiratory rate and body temperature
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| Pulse | pressure wave caused by the expansion and recoil of elastic arteries
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| Where is Radial pulse taken? | on the radial artery at the wrist
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| How often is radial impulse used? | routinely
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| Pulse varies with (3 things) | health, body position, and activity
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| Systemic arterial BP is measured by what method? | the auscultatory method
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| 3 steps of the auscultatory method | 1.A sphygmomanometer is placed on the arm superior to the elbow, 2. Pressure is increased in the cuff until it is greater than systolic pressure in the brachial artery, 3. Pressure is released slowly and the examiner listens with a stethoscope
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| Systolic pressure | The first sound heard and is recorded
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| Diastolic pressure | The pressure when sound disappears is recorded
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| The 2 Alterations in Blood Pressure | Hypotension and Hypertension
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| Hypotension | low BP in which systolic pressure is below 100 mm Hg
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| Hypertension | condition of sustained elevated arterial pressure of 140/90 or higher
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| 2 types of elevation in In Hypertension are | Transient elevations and Chronic (persistent) elevation
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| In Hypertension, Transient elevations are | normal
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| In Hypertension, Transient elevations can be caused by what 3 things | fever, physical exertion, and emotional upset
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| Chronic (persistent) elevation is a major cause of (4 things) | heart failure, vascular disease, renal failure, and stroke
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| 3 types of Hypotension | Orthostatic, Chronic, and Acute
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| Orthostatic hypotension | temporary low BP and dizziness when suddenly rising from a sitting or reclining position
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| Chronic hypotension | hint of poor nutrition and warning sign for Addison’s disease
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| Acute hypotension | important sign of circulatory shock
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| What type of hypotension causes a threat to patients undergoing surgery and those in intensive care units? | Acute hypotension
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| 2 types of Hypertension | Primary (essential) and Secondary
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| Hypertension may be ________ or _________ | transient, persistent
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| Risk factors in primary hypertension include | diet, obesity, age, race, heredity, stress, and smoking
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| Secondary hypertension is due to identifiable disorders, including | excessive renin secretion, arteriosclerosis, and endocrine disorders
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| Blood flow (has another name) | tissue perfusion
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| Blood flow, or tissue perfusion, is involved in (4 things) | Delivery of oxygen and nutrients to, and removal of wastes from, tissue cells, Gas exchange in the lungs, Absorption of nutrients from the digestive tract, Urine formation by the kidneys
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| Blood flow is precisely the right amount to provide | proper tissue function
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| 2 things about Blood velocity | 1.Changes as it travels through the systemic circulation, 2. Is inversely proportional to the cross-sectional area
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| Slow capillary flow (regarding blood velocity) allows adequate time for | exchange between blood and tissues
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|
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