Health Science 2211-Lecture 1

  1. How much blood does your heart pump in a day? in a year?
    • day: 14 000 liters/day
    • year: more than 10 million liters/year
  2. Where is the heart located? (2)
    • in the mediastinum 
    • behind  sternum, in front of vertebral column, between lungs
  3. which direction does the heart point and what does it sit on?
    • heart points to the left 
    • lying/sits on diaphragm
  4. what are the coverings/sac of the heart called?
  5. what is the function of the fibrous pericardium? (2)
    • protects and anchors the heart
    • prevents overstretching
  6. what are the two types of pericardium?
    • fibrous pericardium
    • serous pericardium 
  7. What are the two layers in the serous pericardium?
    • parietal layer of serous pericardium: fused with fibrous pericardium
    • visceral layer of serous pericardium: also called epicardium and it's in direct contact with the heart 
  8. what is the serous (pericardial) fluid?
    fluid found between parietal and visceral pericardia
  9. what are the 3 layers of the heart wall?
    • epicardium
    • myocardium 
    • endocardium
  10. Describe the epicardium.
    thin outer layer of heart wall
  11. describe the myocardium.
    95% of heart wall that is made of cardiac muscle 
  12. describe the endocardium. what is it's function?
    • lines the inner chambers of the heart 
    • minimizes surface friction as blood passes through the heart
  13. what are the 4 chambers in the heart called?
    • atria: upper two chambers
    • ventricles: lower two chambers
  14. what is the auricle and what's it's function?
    • pouch-like structure on the anterior surface of atrium 
    • helps atria hold a greater volume of blood
  15. what is the function of the atria?
    receives blood returning to the heart and push it into the ventricles 
  16. what is the function of the ventricles?
    receive blood from the atria and pump it into systematic and pulmonary circuit
  17. what are the two ventricles divided by?
    divided by the interventricular septum 
  18. The right side of the heart pumps blood into the _____________ circuit.
  19. The left side of the heart pumps blood into the _____________ circuit.
  20. What is the function of the right atrium? (2)
    • receives deoxygenated blood from the superior and inferior vena cava
    • sends blood to right ventricle
  21. what is the function of the right ventricle? (2)
    • receives blood from the right atrium
    • sends blood to pulmonary circulation (lungs) via the pulmonary trunk
  22. What is the function of the left atrium? (2)
    • receives oxygenated blood from the pulmonary circulation (lungs)
    • sends blood to left ventricle
  23. what is the function of the left ventricle? (2)
    • receives blood from the left atrium
    • sends blood to systematic circulation (rest of body) via the aorta
  24. what happens in the pulmonary circuit?
    deoxygenated blood is converted to oxygenated blood by the lungs
  25. what are the 3 structures in the pulmonary circuit?
    • pulmonary arteries
    • capillaries in lungs
    • pulmonary veins
  26. compare the myocardial thickness of the atria and ventricles, which is thicker?
  27. compare the myocardial thickness of the right and left ventricles, which is thicker? why?
    left ventricle because it pumps blood to the systematic circuit (rest of the body) and therefore need more muscle
  28. What is the function of the atrioventricular valve (AV)? (2)
    • separates atria from the ventricles
    • prevents backflow of blood from the ventricles into the atria
  29. what are the 2 types of atrioventricular valves  and where are they located?
    • Tricuspid valve: right AV
    • Bicuspid valve: left AV
  30. what are the functions of the semilunar valves? (2)
    • allow blood to be pumped into the arteries
    • prevent back flow of blood from the arteries into the ventricles
  31. what are the two types of semilunar valves (SL)?
    • aortic semilunar valves
    • pulmonary semilunar valves
  32. how does the heart valves open?
    due to the pressure exerted by the blood
  33. how does the heart valves close?
    when papillary muscles contract
  34. where is the papillary muscles located?
    in ventricle attached to valve cusps by chordae tendineae
  35. what is the function of the chordae tendineae?
    prevent valve cusps from opening into the atrium
  36. where does the sound of the heartbeat come from?
    comes primarily from the turbulence in blood flow caused by the closure of the valves
  37. how does the first heart sound (lubb;S1) occur?
    blood turbulence associated with the closing of the AV valves soon after ventricular systole begins
  38. how does the second heart sound (dupp; S2) occur?
    blood turbulence associated with the closing of the SL valves close to the beginning of the ventricular diastole
  39. Describe the sulci and its function?
    grooves on the outside of the heart that separate the chambers
  40. What does sulci contain and why?
    contain fat and blood vessels that supply blood to the heart muscle
  41. what is the coronary circulation?
    is the circulation of blood in the blood vessels of the cardiac muscle (myocardium)
  42. what is the function of the coronary arteries?
    • supply heart cells with fresh nutrients and oxygen
    • branch of aorta
  43. what is the function of the coronary veins?
    • collect waste and deoxygenated blood from cardiac muscle
    • drains into a large vein called the coronary sinus
  44. coronary sinus empties into ___________.
    right atrium
  45. what is myocardial ischemia? what are the signs?
    • results from reduced blood flow to myocardium which leads to decreased oxygen
    • signs= angina pectoris (severe chest pain, chin, neck, and left arm)
  46. what is a myocardial infraction? (2)
    • aka heart attack, results from complete blockage of a coronary artery
    • tissue dies and is replaced by scar tissue ; heart loses some of its strength
Card Set
Health Science 2211-Lecture 1
Circulatory system: the heart