left and right atriums
left and right ventricles
they have two - four valves
3 this answer is incorrect there are 4 valves in the human heart.
Valves
As in all mammals, horses have four valves in their hearts.
An engine may have two, three, or four valves per cylinder.
An engine may have two, three, or four valves per cylinder.
A standard trumpet(not a piccolo)usually has three valves. However, the higher-pitched piccolo trumpet has four.
There are four valves in the heart--the aortic valve, pulmonary valve, mitral valve, and tricuspid valve--each at the exit of one of the heart's four chambers.
This engine (allowing it is an automotive engine) is a four valve per cylinder engine.
Trumpet has piston valves and occasionally rotary valves, Euphonium/Baritone has piston valves, Tuba has piston valves and french horn has rotary valves. Trombone has a slide, not valves but is also a brass instrament.
There are four valves of the heart: two are located between the atria and ventricles of the heart (called atrioventricular valves) and two are located in the major vessels leaving the valves (called semilunar valves). The left atrioventricular valve is also known as the bicuspid valve or the mitral valve. The right atrioventricular valve is also known as the tricuspid valve. The two semilunar valves are named after the vessel they lie within: the left semilunar valve is called the aortic valve because it lies within the aorta; the right semilunar valve is called the pulmonic valve because it lies within the pulmonary artery.Ruben JoubertThere are four valves in the human heart. There is the aortic vavle, the tricuspid valve, the pulmonary valve and the mitral valve.The are two types of four main valves. The first two are the atrioventricular valves. These valves separate the atria from the ventricles. The two atrioventricular valves are the mitril valve and the tricuspid valve. The other type of valve are the semilunar valves. The semilunar valves are between the ventricles (which pump blood) and the arteries that flow away from the heart. The two semilunar valves are the aortic and pulmonary valves.There are four one-way valves in a human heart. These are the only valves in the heart.There are four valves in the heart (not counting the valve of the coronary, the isotonic valve and the valve of the inferior vena cava): two atrioventricular valves (mitral valve and tricuspid valve); and two semilunar valves (aortic valve and pulmonic valve).
It depends on which valves you are referring to. On a four stoke engine there are at least two per cylinder.