Which is the final event that occurs when a star is forming? O The outer layer of the star expands.
O Gravity pulls gas and dust together.
A black hole forms as the core collapses.
Nuclear fusion begins under high pressure.

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.

where in your body is there an enzyme that does function at a high or low ph? what is the name of that enzyme and its function?