Anatomy and Physiology 2 Exam 2

  1. Diastolic pressure
    lowest arterial pressure during diastole (heart relaxation)
  2. What factors influence blood pressure?
    • Hemorrahaging
    • Dehydration
    • Edema
  3. What mechanisms regulate the movement of fluids between capillaries and interstitial spaces (CHP, BCOP)?
    • Net hydrostatic pressure tends to push water and solutes out of capillaries and into interstitial fluid: NHP=CHP-IHP
    • Net colloid osmotic pressure tends to pull water and solutes into a capillary from the interstitial fluid: NCOP=BCOP-ICOP
    • NHP and NCOP oppose eacher and the larger force wins
  4. Blood Flow
    Is the volume of blood that flows through any tissue in a given time period.

    Blood flow is equal to CO=HRxSV
  5. How does blood flow?
    From regions of high pressure to regions of lower pressure

    The greater the pressure difference, the greater the blood flow

    The higher the resistance, the smaller the blood flow
  6. Blood Pressure (BP)
    • The hydrostatic pressure exerted by blood on the walls of a blood vessel
    • Generated by the contraction of the ventricles
    • Highest in Aorta and large systemic arteries
  7. Systolic pressure
    highest arterial pressure attained during systole (heart contraction. Lup
  8. Tunica Externa
    • Fibrous connective tissue
    • Provide support and elasticity
  9. Tunica Media
    • Smooth muscle fibers
    • Elastic fibers that allow for extreme amounts of pressure
    • Stretch and go back
    • cause changes in blood vessel diameter
  10. Tnica interna (intima)
    • Endothelium lining inside of blood vessel
    • Connective tissue
    • Touches the blood
    • continuous with endocardium in heart
  11. Arteries
    • Thicker tunica media
    • more elastic fibers
    • built to resist pressure
    • always look circular
  12. Veins
    • contain valves
    • tinner tunica media
    • look flattened
    • larger than arteries
    • collect blood from all the tissues and organs and return it to the heart
  13. How are arteries classified?
    Elastic (conducting) large vessels wihich transport large volumes of blood away from the heart

    Muscular (distribution) transport blood to skeletal muscle and internal organs

    Arterioles resistance vessels
  14. Capillaries
    • Most numerous and smallest vessels
    • Exchange vessels
  15. Capillary Beds
    • function as an interconnected network
    • exchange of materials
  16. Precapillary sphincter
    • regulate blood flow into capillary bed
    • vasomotion-cyclic contraction and relaxation of sphincter
    • flow is based on tissue need
  17. Anastomosis
    interconnections between arteries and veins or ateries to arteries and veins to veins
  18. How do oxygen, carbon dioxide, and water move between tissues and capillary beds?
    Oxygen and nutrients diffuse from blood into interstitial fluid and into cells

    Carbon dioxide and wastes diffuse from cells into interstitial fluid and into blood

    Water is exchanged by osmosis
  19. How are veins classified?
    Venules-collect blood from capillary beds and are the smallest venous vessels

    Medium-sized veins-range from 2-9mm

    Large veins-include superior and inferior vena cava
  20. Why do veins have valves?
    BP in the venules and medium veins is so low that it cannot oppose gravity. Blood wants to pool in lower extremitites.
  21. Arterial blood pressure (BP)
    • pressure from aorta to arteroles (100-35mmHg)
    • maintains blood flow through the capillary beds
    • rises during ventricular systole and falls during ventricular diastole
  22. Capillary hydrostatic pressure (CHP)
    pressure within capillary beds (35-18mm Hg)
  23. Venous pressure
    the pressure within the venous system (18mmHg)
  24. MAP
    average blood pressure in arteries

    MAP = DP+1/3(systolic BP-diastolic BP)
  25. Resistance
    resistance of the cardiovascular system opposes the movent of blood

    the result of friction between blood and walls of the blood vessels
  26. What does resistance depend on?
    • Total vessel length
    • vessel diameter
    • blood viscosity
    • turbulence
  27. Total peripheral resistance (TPR)
    The sum of all vascular resistance

    Major function of arterioles is to control this by vasoconstriction and vasodilation
  28. Peripheral resistance
    the resistance of the arterial system

    for blood to flow the pressure gradient must be great enough to overcome this

    Flow = P/R

    • Increase in pressure = increase in flow
    • Increase in resistance = decrese in flow
  29. Capillary Exchange
    • Movement of substances from blood in the capillaries to interstitial space
    • Assists in the transport of lipids and tissue proteins
    • accelerates the distribution of nutrients
    • carries toxins and other chemical stimuli to lymphoid tissues
  30. Diffusion
    • Movement from an area of high concentration to an area of low concentration
    • rapid exchange of respiratory gases O2 and CO2
  31. Filtration
    • pressure-driven movement of fluid and solutes from the blood capillaries into interstitial fluid
    • circulatory system will push material out to the tissues
  32. Reabsorption
    • pressure-driven movent from interstitial fluid into blood capillaries
    • pushes material into bloodstream
  33. What promotes filtration?
    Blood hydrosatic pressure (CHP)
  34. What promotes reabsorption?
    Blood colloid osmotic pressure (BCOP)
  35. Net filtration pressure
    • the balance between CHP and BCOP
    • which one is bigger determines which one moves

  36. Hemorrhaging
    • blood volume and pressure drops
    • CHP lowers NFP fluid moves from tissues into blood
    • known as recall of fluids
  37. Dehydration
    plasma volume decreases, increases BCOP fluid is recalled from tissues
  38. Edema
    • abnormal accumulation of interstitial fluid and one happens
    • CHP rises-increases in arterial, venous, or total circulatory pressure
    • BCOP declines-capillary damage, starvation
  39. Venouse pressure and venous return
    Venous pressure determines venous return which has an impact on CO
  40. Muscular compression
    • the contractions of skeletal muscles near a vein compress it
    • Fainting or syncope
  41. Repiratory pump
    • as inhale your thoracic cavity expands and pressure within the pleural cavity decreases. This drop in pressure pulls blood into the IVC and atrium from smaller veins
    • Area of high pressure to an area of low pressure
  42. Autoregulation accelerates the blood flow how? And what performs this?
    Vasodilators and local vasoconstrictors(prostaglandins, thromboxanes)

    • Decreased tissue O2 levels or increased CO2 levels
    • Generation of lactic acid
    • Release of nitiric acid
    • Rising K+ or H+ concentrations in interstitial fluid
    • Local inflammation
    • Elevated temperature
  43. Neural mechanisms do what?
    Adjust CO and PR to maintain vital organ blood flow
  44. What are the medullary cneter of regulatory activity?
    • Cardiac centers
    • Vasomotor centers
  45. Cardiac centers
    • cardioacceleratory-sympathetic
    • cardioinhibitory-parasympathetic
    • Control HR, contractility-->blood flow, BP
  46. Vasomotor centers
    • Vasocontriction-via adrenergic release of NE-cause more resistance when there is a change
    • Vasodilation-via direct or indirect release of NO-can have cnetral or local dilation
  47. Baraoreceoptor
    • influence cardiac centers or vasomotor center
    • monitor pressure
    • in walls of expandable organs
    • also located: Corotid arteries-corotid sinus, Arch of aorta-aortic sinus, and walls of the rt. atrium
  48. Chemoreceptor reflexes
    • Monitor O2 levels and CO2 concentration
    • Located in: Carotid arteries-carotid bodies and Aorta-aortic bodies
  49. Hormones that play a part in cardiovascular regulation
    • Antidiuretic homone-released in response to decreased blood volume(against pee)
    • Angiotensin II-releasd in response to a fall in blood pressure(released by kidneys to red bone marrow)
    • Erythropoietin-released if BP fall or O2 levels are abnormally low
    • Natriuretic peptides-released in response to excessive right atril stretch(increase pee and gets rid of sodium)
  50. What are the arteries of the brain?
    • Common carotid arteries
    • External caratid artery
    • Internal carotid artery
    • Ophthalmic artery
    • Anterior cerebral artery
    • Middle cerebral artery
    • L/R vertebral arteries
    • Basilic artery
    • Circle of Willis
  51. Comon carotid arteries
    ascend the neck and divide into External and Internal carotids
  52. External carotid
    supplies the neck, esophagus, pharynx, larynx, lower jaw, and face(nothing with brain)
  53. Internal carotid
    • Enter into carotid foramen and delivers blood to the brain and divides into ophthalmic artery, anterior cerebral artery, middle cerebral artery
    • Vertebral
  54. Circle of Willis
    • Anastamosis
    • Guarantees blood supply to the brain(blood will have an alternate route to go through if there is a block)
  55. Hepatic Portal System
    • Blood leaving the capillaries supplied by the celia, superior, and inferior mesenteric arteries flows into this.
    • Centralizes blood from the GI tract
    • Nutrient procession
    • Detoxification
  56. What is the only digestive organ that drains directly into the IVC?
  57. Fetal Circulation
    • 1. Umbilical cord
    • 2. Unbilical arteries(deoxygenated blood and waste the the placenta)
    • 3. Unbilical vein(oxygenated blood is returned to the fetus)
    • 4. Drains into Hepatic portal vein and Ductus venosus in the fetal liver
    • 5. Drains into the IVC
    • 6.Foramen ovale-hole between R and L atrium
    • 7. Ductus arteriousus connects to Aorta
Card Set
Anatomy and Physiology 2 Exam 2
Anatomy and Physiology 2 Exam 2 chap 21