text: The<unk>  of the<unk><unk>  serve to seal the<unk><unk>  when closed. There are normally three<unk>  for each<unk> except the mitral<unk> (hence its alternate name, "bicuspid<unk> .)
  "Nodules" are located at the tip of the<unk>  to form a tighter seal.
option_0: Cusps of heart valves
option_1: Heart valve
option_2: Electrical conduction system of the heart
option_3: Pulmonary valve
option_4: Apex of the heart
option_5: Pulmonary circulation
option_6: Base of the heart
option_7: Coronary circulation