47. Name the valve:

31. Name the chamber:

42. Is this the wall of the left ventricle or the right ventricle?

43. Name the wall:

37. Name this valve:

39. Name this valve:

14. A condition in which atrial impulses are generated & spread throughout the atria, but no atrial impulses are conducted to the ventricles describes:  

35. Name this valve:

12. The conduction system of the heart does not include:  

17. Small, ridge-like muscles, forming a criss-crossing network of muscles seen mostly in the walls of the ventricles (especially the right side) are called: