tricuspid valve: valve with three cusps; situated between the right atrium and the right ventricle; allows blood to pass from atrium to ventricle and closes to prevent backflow when the ventricle contracts
atrioventricular valve: either of two heart valves through which blood flows from the atria to the ventricles; prevents return of blood to the atrium
sugar beet: form of the common beet having a sweet white root from which sugar is obtained