What is an ecosystem and what does it consist of?

An ecosystem is a large community of living organisms (plants, animals and microbes) in a particular area. The living and physical components are linked together through nutrient cycles and energy flows. Ecosystems are of any size, but usually they are in particular place. An ecosystem consists of the biological community that occurs in some local, and the physical and chemical factors that make up its abiotic(non-living) environment. There are many examples of ecosystems -- a pond, a forest, an estuary, a grassland.

Explanation:

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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.

the answer is b. glad to .