CV: blood vessels & circulation
Vascular structure that returns blood to atria of heart
Veins
A cross section of tissue shows several small, thin-walled vessels with very little smooth muscle tissue in the tunica media. Which type of vessels are these?
Veins; arteries & arterioles have large amount of smooth muscle tissue in a thick, well-developed tunica media
A blockage of which branch of the aortic arch would interfere with blood flow to the left arm?
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A blood sample taken from the umbilical cord contains high levels of oxygen and nutrients, and low levels of carbon dioxide and waste products. Is this sample from an umbilical artery or an umbilical vein? Explain.
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Define aneurysm.
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Define thrombus.
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Describe the general distribution of major arteries and veins in the neck and limbs. What functional advantage does this distribution provide?
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Describe what the cardiovascular system provides for all other body systems.
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Explain the role of aldosterone and ADH in long-term restoration of blood volume.
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Grace is in an automobile accident, and her celiac trunk is ruptured. Which organs will be affected most directly by this injury?
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Identify components of the cardiovascular system that are affected by age.
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Identify the three general functional patterns of the body's blood vessels.
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Identify the two circuits of the cardiovascular system.
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Name the blood vessels that enter and exit the lungs, and indicate the relative oxygen content of the blood in each.
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Name the immediate and long-term problems related to the cardiovascular response to hemorrhaging.
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Name the structures that are vital to fetal circulation but cease to function at birth. What becomes of each of these structures?
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Name the umbilical vessels that constitute the placental blood supply.
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Trace the path of a drop of blood through the lungs, beginning at the right ventricle and ending at the left atrium.
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What is the relationship between the skeletal system and cardiovascular system?
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Why does blood pressure increase during exercise?
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Why would compression of the common carotid arteries cause a person to lose consciousness?
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Bulge in weakened wall of blood vessel, generally an artery
Aneurysm
In a healthy individual, where is blood pressure greater: at the aorta or at the inferior vena cava? Explain.
Aorta; blood, like other fluids, moves along pressure gradient from areas of high pressure to low pressure
Vascular structure carrying blood away from heart
Arteries
Why are valves found in veins, but not arteries?
Because very low blood pressure in venous circulation makes movement of blood against pull of gravity difficult, blood flow within peripheral veins depends on contractions of skeletal muscles to propel blood, and on valves to prevent blood from backing up
Vascular structure where chemical and gaseous exchange occurs
Capillaries
Describe the actions of vasodilators & vasoconstrictors.
Vasodilators increase blood flow locally (that is, through their tissue of origin) by promoting dilation of precapillary sphincters; Vasoconstrictors decrease local blood flow by constricting precapillary sphincters
Abnormal accumulation of fluid in peripheral tissues
Edema
Check point #1
1-4
Check point #4
11-13
Check point #5
14-15
Check point #6
16-17
Check point #7
18-21
Check point #8
22-24
Check point #9
25-27
Check point #10
28-29
Check point #2
5-7
Check point #3
8-10
Vascular pathway of blood flow
Arteries → Arterioles → Capillaries → Venules → Veins
Five general classes of blood vessels
Arteries, arterioles, capillaries, venules, and veins
Vascular structure that branches from arteries to capillaries
Arterioles
Condition characterized by thickening & toughening of arterial walls
Arteriosclerosis
Type of arteriosclerosis characterized by changes in endothelial lining & formation of plaque
Atherosclerosis
How would slightly compressing the common carotid artery affect your heart rate?
Elevates heart rate; compression decreases blood pressure at carotid sinus (location of carotid baroreceptors), which stimulates cardioacceleratory centers in medulla oblongata to increase sympathetic stimulation, which raises heart rate
Abnormally high blood pressure; usually defined in adults as blood pressure higher than 140/90
Hypertension
Having an excessive blood volume
Hypervolemic
Blood pressure so low that circulation to vital organs may be impaired
Hypotension
Having a low blood pressure
Hypovolemic
What effect would relaxation of precapillary sphincters have on blood flow through a tissue?
Increase blood flow to tissue
What affect would vasoconstriction of the renal artery have on systemic blood pressure & blood volume?
Increases in systemic blood pressure & volume; such vasoconstriction would decrease both blood pressure & flow at kidney, which would respond by releasing more renin; increased renin would lead to an increase in antiotension II, which would elevate blood pressure and volume
Low blood pressure upon standing, often accompanied by dizziness or fainting; results from failure of regulatory mechanisms that increase blood pressure to maintain adequate blood flow to brain
Orthostatic hypotension
Inflammation of a vein
Phlebitis
Circulatory blockage caused by trapping of an embolus (often a detached thrombus) in a pulmonary artery
Pulmonary embolism
Acute circulatory crisis marked by hypotension & inadequate peripheral blood flow
Shock
Device that measures blood pressure using an inflatable cuff placed around a limb
Sphygmomanometer
Stationary blood clot within blood vessel
Thrombus
Identify factors that contribute to total peripheral resistance.
Total peripheral resistance reflects combination of vascular resistance, vessel length, vessel diameter, blood viscosity, and turbulence.
Outermost layer of vessel wall, forms sheath of connective tissue around vessel; its collagen fibers may intertwine with those of adjacent tissues, stabilizing and anchoring blood vessel
Tunica externa (or tunica adventitia)
Innermost layer of vessel wall, includes endothelial lining of vessel & an underlying layer of connective tissue dominated by elastic fibers
Tunica intima (or tunica interna)
Middle layer of vessel wall, contains smooth muscle tissue in framework of collagen & elastic fibers. When these smooth muscles contract, vessel diameter decreases; when they relax, vessel diameter increases.
Tunica media
Sagging, swollen veins distorted by gravity & by failure of venous valves
Varicose veins
Smallest vessels of venous system
Venules
While standing in the hot sun, Sally begins to feel light-headed and then faints. Explain what happened?
When standing for long period of time, blood pools in lower extremities, decreasing venous return to heart; resulting decline in cardiac output reduces blood flow to brain, causing lightheadedness and fainting; hot day add to this effect: loss of body water through sweating reduces blood volume (and venous return)