The atomic number of an atom is the number of in the atom's nucleus.

Protons

Explanation: Every atom is defined by its protons every element. So if it has 1 proton its hydrogen no matter what. If it has 2 protons its helium no matter what and so on. So if you know the number of protons you know the element.

The atomic number tells you the number of protons that are in the core of a particular element.

answer; ///(statins)/aka as hmg coa

the oxygenated blood then leaves the lungs through pulmonary veins, which return it to the left heart, completing the pulmonary cycle. this blood then enters the left atrium, which pumps it through the mitral valve into the left ventricle. from the left ventricle, the blood passes through the aortic valve to the aorta.

deoxygenated blood leaves through the right ventricle through the pulmonary artery. from the right atrium, the blood is pumped through the tricuspid valve (or right atrioventricular valve), into the right ventricle.