Heart valve called the "semilunar valves". These two arteries receive blood from the ventricles and their semilunar valves permit blood to be forced into the arteries, and prevent backflow from the arteries into the ventricles. These valves do not have chordae tendineae, and are more similar to the valves in veins than they are to the atrioventricular valves. The closure of the semilunar valves causes the second heart sound. The aortic valve, which has three cusps, lies between the left ventricle and the aorta. During ventricular systole, pressure rises in the left ventricle and when it is greater than the pressure in
How Many Birds How Many Birds "How Many Birds" is a song written by Barry Gibb, recorded by the Bee Gees in 1966 for the "Spicks and Specks" album. Recording took place at St. Clair Studios, Hurstville outside Sydney. The song was recorded on one-track tape machines and required the use of sound-on-sound for all overdubs. "How Many Birds" was recorded around April and May 1966 as part of the sessions for what became the Spicks and Specks album. The song starts with a guitar riff and the chord became E as Barry sings the introduction. After Barry sings the lines, the song