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2013-10-12 19:45:09
Cardiovascular System

Cardiovascular system
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  1. _______ circulation transports blood from the heart to the lungs and back to the heart
  2. __________ circulation delivers blood from the heart to all of the parts of the body and back to the heart
  3. ____________ carry blood away from the heart toward either the lung or teh periphery
  4. the arteries brance extensively, forming small arteries called:
  5. the smallest of teh arterioles branch to form:
  6. the site of all oxygen and carbon dioxide exchange within the pulmonary and peripheral circulation AND nutrient exchange between tissue and blood within peripheral circulations takes places within the:
  7. vessels that carry blood toward the heart are called:
  8. small veins that carry blood toward heart:
  9. blood that is returning to the heart is called:
    venous blood
  10. blood that is leaving the heart and traveling toward other bodily tissues or lungs is called:
    arterial blood
  11. which side of the heart receives blood from the peripheral circulation and pumps blood to the pulmonary circulation?
    the right side of the heart
  12. which side of the heart receives blood from the pulmonary circulation and pumps blood to the peripheral circulation?
    the left side of the heart
  13. blood returning to the heart from the peripheral circulation enters the:
    right atrium (right upper chamber)
  14. blood from the pulmonary circulation enters the:
    left atrium (left upper chamber)
  15. blood from upper right atrium passes thru the _______ one way valve into the ventricles
  16. blood leaving teh ventricles passes through the __________ one way valve into the aorta, the large artery leaving the Left ventricle
    bicuspid artioventricular valve
  17. why are one-way valves important?
    prevent backflow of blood in the wrong direction
  18. a tough, membranous sac that encases the heart is called the:
  19. trace the flow of blood thru the heart:
    • -blood enters the R artrium from superior & inferior vena cava
    • -pass thru AV valve into R ventricle
    • -pumped through valve into pulmonary trunk
    • - passes through pulmonary arteries to lungs
    • -blood gets oxygenated & returned to L atrium via pulmonary veins
    • - passes thru AV valve into L venticle
    • -pumped thru valve into artora & out to body
  20. the artery which supplys the heart with its blood supply; which it branches off of the aorta is called:
    coronary artery

    • -blood has just returned from pulmonary circulation; fully oxygenated
    • -blood pressure is highest in aorta & very high in arteries supplying heart
    • -all major arteries & veins of the heart are on outer surface of heart, so that they are not compressed during cardiac contraction
  21. intercommunication between two arteries that ensures blood flow to an area, even if an artery supplying an area is fully or partially blocked is called:
  22. define systole:

    define diastole:
    • systole: refers to the contraction phase of the cardiac cycle
    • diastole: refers to the relaxation phase of the cardiac cycle
  23. describe the intrinsic control of cardiac muscle:
    • -ability to initiate its own impulses for contraction at relativeyly regular time intervals is called autorhythmaticity
    • -specialized nervous tissue; pacemaker of cardiac contraction is the SA Node
    • -specialized nervous tissue of the AV Node delays the impulse to contract approximately 1/10 of a second, allowing the atria to contract before the ventricles
    • - purkinje fibers rapidly spreak impulse to contract throughout the ventricles
  24. describe the extrinsic control of cardiac muscle:
    • -2 major factors that influence heart rate are the sympathetic and parasympathetic branches of autonomic nervous system
    • -at the SA and AV nodes, the parasympathetic nerve fibers release acetylcholine, which results in a decrease in heart rate
    • -at the SA and AV nodes, sympathetic fibers release norepinephrine, which increases the heart rate
    • -endocrine glands
    • -a training inducded resting bradycardia or slowing of the heart rate to less than 60 beats/min
  25. how is cardiac muscle (myocardium) different from skeletal muscle:
    • autorhythmaticity; capable of initiating impulse
    • presences of intercalated discs; allows impuls to contract from one muscle fiber to another
    • syncytial contraction: fibers contract simultaneously

    • similar to skeletal
    • capable of contraction and force generation
  26. what are the characteristics of the fibers in myocardium (heart muscle):
    • have high mitochondrial density
    • have extensive capillary network
    • use aerobic energy for contraction
  27. which wall of the cardiac chambers are the thickest? why
    • the thicker the wall; the greater the force
    • L ventricle must pump blood to the entire body against higher blood pressure, so the L ventricle has the greatest wall thickness
  28. what are the adaptions made to cardiac wall thickness in regards to phyiscal training:
    • thickening of L ventricle wall; allowing it to easily overcome a greater BP observed during activity
    • increased thickness of the L ventricle wall because of physcial training does NOT exceed the upper limit of what is considered normal
    • increased L ventricular mass (total amout of mycardium surrounding L ventricle
    • considered a normal physiological adaption
    • no increase in wall thickness of the atria & right ventricle
  29. what are the adpations of the cardiac wall thickness in regards to chronic hypertension:
    • L ventricluar wall thickness increases
    • increased wall thickness due to chronic hypertension DOES exceed the upper limit of what is considered normal
    • increased L ventricular mass
    • considered a pathological adaption of the myocardium
  30. describe the electrical activity of the heart on an ECG

    P wave:
    PQ segment:
    QRS interval:
    ST: segment
    T wave:
    • P wave: atrial contraction, atrial depolarization
    • PQ segment: (1/10 of a second) no electrical activity; caused by AV node holding ventricluar contraction
    • QRS interval: ventricular depolarization; contraction of the ventricles
    • ST segment: peroid of time after ventricular contraction until the start of ventricular relaxation
    • T wave: ventricular relaxation and reploarization
  31. what does a depression in the ST segment on an ECG indicate?
    ischemia (decreased blood flow, resulting in insufficient oxygen delivery to myocardium)
  32. define cardiac output:
    how is cardiac output determined:
    what are the typical cardica outputs for men/women:
    describe the variations of cardiac output of trained and untrained individuals:
    • cardiac output: the amount of blood pumped per minute by the heart; symbolized by 'Q'
    • determined: heart rate X stroke volume; HR x SV= Q
    • typical for men: 5 L min
    • typical for women: 4.5 L min
    • varitations: resting cardiac output is about the same in trained & untrained people; however trained people have a lower HR & a higher SV
  33. the amount of blood pumped per contraction of teh ventricles is called:
    stroke volume
  34. in regards to heart rate, describe the regulation of cardiac output:
    • heart rate tends to increase with age and decrease with cardiovascular fitness
    • HR is affected by envrionmental conditions such as altitude and temperature
    • Max HR remains constant day to day and changes slightly from year to year
    • HR Max= 220- age
  35. define end-diasotolic volume:
    define end systolic volume:
    state the equation to relate stroke volume to  EDV&ESV:
    • EDV: the amount of blood in the ventricles at the end of diastolic, relaxation, phase of the ventricles
    • ESV: the amount of blood left in the ventricles at the end of the systolic phase, or after contraction of the ventricles
    • SV= EDV-ESV
  36. If EDV increases and ESV remains constant, the SV will [increase/decrease]
    SV will increase
  37. list 3 factors of exercise that can increase stroke volume:
    • frank starling mechanism: more blood in the ventricles causes it to stretch more and contract with more force
    • increased ventricular contractility (without end-diastolic volume increases)
    • decreased total peripheral resistance due to increased vasodilation of blood vessels to active muscles
  38. in regulation of cardiac output, the ratio of available blood to be pumped is called:
    • ejection fraction (EF)
    • EF=EDV/SV
  39. what are the characteristics of the relationship between ventricular volume and training:
    endurance training increases end-diastolic volume, thus increasing the stroke volume & decreasing HR

    • moderately trained or untrained
    • stroke volume increases with exercise intensity  up to 40-50% of peak O2 consumption
    • stroke volume does not increase at greater intensities
    • HR increases with cardiac output up to max workloads
    • HR is a good indicator of training intensity
  40. what are the 2 laws governing blood flow:
    • blood flows from areas of high pressure to areas of lower perssure
    • (an area of high BP is in the aorta, low BP in the L ventricle)
    • the rate of flow is proportional to the pressure difference between 2 ends of vessels or between 2 chambers
  41. describe 3 ways to increase flow within the cardiovascular sytstem:
    • increase the pressure difference between 2 ends of vessels or between 2 chambers
    • decrease the resistance to flow
    • increase the readius of the vessel

    blood flow = change in pressure / resistance to flow
  42. the highest BP occurs during _____, and the lowest BP occurs during______.

    how is BP measurered:
    what is typically resting BP:
    higest BP occurs during systole, lowest BP occurs during diastole

    • measuered: sphygmomanometer + stethsocop
    • typically resting BP: 120/80
  43. how does increased cardiac output (as in exercise) affect BP:

    how does an increased capacitace affect BP:

    how does aerobic & weight training affect BP:
    • increased cardiac output = increased BP
    • increased capacitace = increased BP
    • aerobic & weight training: reduce resting BP
  44. describe the composition of plasma:
    • contributes to 55-60% of total blood volume
    • composed of 90% water, 7 % plasma proteins, and 3 % nutirents, electrolytes, hormones, enzymes, antibodies, and other substances

    • may decrease in volume as much as 10% during intense physical activity
    • can increase as much as 10% at rest because of adaption to training
  45. what are the 2 major components of blood?
    plasma and formed elements
  46. describe the composition of formed elements:
    • contributes to 40-45% of total blood volume
    • comprised of 99% of red blood cells
    • 1% white blood cells and platelets
  47. what is the important fxn of platelets:
    important for blood clotting

    can contribute to heart attack, stroke, and plaque build up
  48. the percentage of the total blood volume composed of formed elements is referred to as:

    how does an increase in plasma affect this term:
    how does training affect this term and why is it important:

    an increase in plasma, results in a slight decrease in hematocrit

    training increases the blood volume,  it is important because it results in the  increase of total oxygen that can be delivered to the metabolicallly active tissue
  49. what is the main fxn of red blood cells?
    what particular substance makes this fxn possible?
    • fxn: transporting oxygen
    • made possible by: hemoglobin: composed of protein (globin) and an iron-containing pigment (heme) which is necessary for the binding of oxygen
  50. what are the characteristics of red blood cells:
    • produced in the bone marrow of long bones
    • prior to being released into the blood, the nucleus is removed, so they cannot reproduce or repair themselves
    • lifespan of 4 months
    • destruction and production are balanced
  51. in regards to plasma volume... at the onset of aerobic or weight training what is the:

    acute effect of aerobic training:
    the net effect of aerobic/weight training:
    effect of prolonged aerobic:
    acute effect weight training:
    chronic long term aerobic training effect:
    • actue aerobic: substantial reduction of plasma volume
    • net effect of aerboic: increased # of RBCs per unit volume of blood & increased oxygen-carrying capacity
    • prolonged aerobic: plasma vol. decrease 10-20 %
    • acute weight training: plasma volume decreases 0-22%  (not moving around much)
    • long-term aerobic: plasma volume increases 12-20% (fxn: more blood, more volume, stroke volume increase)
  52. what is the negative effect of increased plasma volume with no other changes?
    • anemia
    • blood is too saturated
    • not enough oxygen
  53. what are the diffences between endurance vs. strenth training adaptions at rest:
    • adaptations due to endurance training
    • increase cardiac output  ( stroke volume increases from #1. increased plasma #2. decreased HR)
    • increased oxygen delivery to skeletal muscles (increased RBC)
    • increased endurance performance

    • adaptions due to weight training
    • increased ability to maintain cardiac output against increased BP during weight training (thicker L ventricle wall)
  54. the difference between the amount of oxygen in 100 mL of the arterial blood entering a tissue and amount of oxygen in the 100 mL of venous blood leaving the tissue is called:
    arterial-venous oxygen differnece (a-v O2 diff)

    during exercise, more oxygen is taken out of the blood, which increases the a-v O2 diff

    repersents difference for all body's tissues
  55. what is the (a-v O2 diff) at rest:
    what is the (a-v O2 diff) during exercise:
    • at rest: 5 mL O2 per 100 mL of blood
    • during exercise: increases to 15 mL O2 per 100 mL of blood
  56. the calculation of oxygen delivery or oxygen consumption as a product of blood flow multiplied by (a-v O2 diff) is called:
    the fick equation

    oxygen delivery for whole body (cardiac output (Q) = blood flow)

    VO2 = Q x (a-vO2 diff)

    increaseing either Q or (a-vO2 diff) or combination can increase VO2 for whole body
  57. describe the redistribution of blood flow during exercise of the:

    skeletal muscles:
    • skeletal muscles
    • at rest: 15-20% of caridac output goes to skeletal muscles
    • during maximal exericse: 80-85% goes to skeletal muscles

    • heart
    • both at rest and during exercise: 4%
    • rest: 200 mL  exercise: 1,000 mL
    • increase 4-5x during execerise, due to cardiac output, not redistribution

    • brain
    • at rest: 700 mL
    • exercise: 900 mL
  58. what are the factos that affect the redistribution of blood:
    • parallel circuitry
    • vasodilation: increase in radius, increase blood flow to the tissue
    • vasoconstriction: decrease in radius, decrease in blood flow to other tissues not muscle
    • percapillary sphincters: musclar rings at entrance of capillary beds
  59. describe the extrinsic control of vasoconstriction and vasodilation:
    • release of norepinephrine by sympathetic nerves causes vasoconstriction
    • release of epinephrine by sympathetic nerves can cause both vasoconstriction and vasodilation
  60. describe the intrinstic control of vasodilation and vasoconstriction:
    autoregulation: changes in skeletal muscles during exercise that stimulate muscle chemoreceptors & increase vasodilation
  61. describe the 3 ways of increasing venous return:
    • venoconstriction
    • constriction of veins via sympathetic stimulation
    • only effective in tissues other than skeletal muscles

    • muscle pump
    • rhythmic muscle contractions propelling blood to heart through one-way valves

    • respiratory pump
    • changes in intrathoracic pressure during expiration & inspriation, forcing blood toward heart