Development of Heart

  1. What week does the heart start to function?
  2. The embryo initially divides into two cavities; These are?
    • Amniotic
    • Yolk
  3. What connects the two embryonic cavities to the embryo?
    Connecting Stock
  4. What does the connecting stock evolve into?
    Umbilical chord
  5. Blood islands encompass the embryo in the what?
  6. Blood islands eventually fuse to form what?
    Blood vessels
  7. Fusing blood islands fuse to form blood vessles in the trophoblast and the what?
    Tertiary Chorionic Villus
  8. What is the mesoderm?
    One layer of the primary germ cells and is responsible for connective tissue
  9. Which end does the heart begin to form from?
    Cranial (Head) end
  10. What is the cardiogenic area?
    Small group of mesodermal cells responsible for heart formation forming a pair of elongated strands called cardiogenic cords
  11. How do the cardiogenic cords form the heart?
    • Lateral Folding
    • Fuse

    This is called the Primitive Heart Tube
  12. Where can blood islands be found?
    Surface of yolk sack
  13. Cavities form between the blood islands. Why?
    Do give hollow tubes - creating vessels
  14. What is the pericardial coelom?
    Section of the cardiogenic area that folds to surround the heart to create the pericardial sack
  15. What are the endothelial strands known as in early development?
    Angioplastic cords
  16. Why does the Oropharyngeal membrane fold posterior to the brain?
    Different rates of growth
  17. What is cardiac jelly?
    Gelatinous connective tissue
  18. What is the endocardium developed from?
    Endothelial tube
  19. What is the myocardium developed from?
    Primordial myocardium
  20. How do we know the arterial end of the heart tube?
    Its where blood exits
  21. How do we know the venous end of the heart tube?
    Its where blood enters
  22. What does the sinus venosus develop into?
    • Right atrium
    • Coronary sinus
    • SA node
  23. What does the bulbis cordis develop into?
    R ventricle
  24. What are the 5 main regoins of the developing heart?
    • Sinus venosus
    • Atrium
    • Ventricle
    • Bulbus cordis
    • Truncus arteriosus
  25. Function of sinus venosus?
    Receive blood from all veins in embryo
  26. What does the atrium develop into?
    Right and Left atrium
  27. What does the ventricle develop into?
    Left ventricle
  28. What does the truncus arteriosus develop into?
    Ascending aorta and pulmonary trunk
  29. Elongation causes folding of the tubes into the heart: how?
    Atrial and venous ends are confined by the pericardium
  30. What is the job of the cardiac jelly?
    Seprates epicardium, myocardium and endocardium
  31. What are the 3 pairs of veins that drain into the heart?
    • Vitelline
    • Umbilical
    • Cardial Veins
  32. What do the vitelline veins do?
    Return poorly oxygenated blood from the yolk sac
  33. What do the umbillical veins do?
    Carry well oxygenated blood from the chorionic villi of the embryonic placenta
  34. What do the cardial veins do?
    Return poorly oxygenated blood from the body of the embryo
  35. How does the ductus venosus effect the liver?
    Develops in liver connecting the umbilical vein to the IVC, meaning no blood travels through the hepatic capillary network
  36. Which is the only vein to carry oxygenated blood?
  37. What muscle and muscle movement give rise to the first contraction?
    • Continuous muscle
    • Peristalsis motion
  38. What are endocardial cushions?
    Pinching of endocardium to form atrioventricular canals
  39. What is the foramen ovale?
    Opening in the interatrial septum (IAS)
  40. What is the septum primum?
    Upper most region of the IAS
  41. What is the foramen primum?
    The lowst hole in IAS
  42. What is the foramen secundum?
    The highest hole
  43. What is the process of Foramen Ovale?
    • Septum primum begins to form downwards
    • Foramen primum begins to form upwards
    • Foramum primum fuses with endocardial cushions (closed)
    • Septum sarcundum (upper limb) begins to form downwards
    • Septum sarcundum (lower limb) begins to form upwards
    • Creates a foramen ovale
    • Septum primum degenerates
    • Valve is created - foramen ovale
  44. How is the foramen ovale closed?
    Increase in LA pressure compared to right - fusion
  45. How to pulmonary veins associate with LA?
    Grow independently onto LA
  46. Name 3 shunts and their purpose during development:
    • Foramen Ovale - R - L atrium
    • Ductus arteriosis - Pulm Trunk - Aorta
    • Ductus Venosis - Umb Vein - IVC (bypasses liver)
  47. What are the 3 different types of ASD?
    • Ostium secumdum - Middle Septum
    • Ostium Primum defect (endocardial cushion defect) - Lower Septum
    • Sinus Venosus Defect - Roof of Septum
  48. What are the 4 structural complications with the heart in tetralogy of Fallot
    • VSD
    • Pulmonary Stenosis
    • Enlarged R Ventricle
    • Anterior deviation of the aorta
  49. What is a patent ductus arteriosis?
    Blood vessel between the aorta and pulmonary trunk remains open, causing a back flow of blood into the R ventricle
Card Set
Development of Heart