What is the purpose of photosynthesis

It's not oxygen production. The primary function of photosynthesis is to convert solar energy into chemical energy and then store that chemical energy for future use. For the most part, the planet's living systems are powered by this process.

Explanation:

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.

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