Question

define cellular respiration?describe double circulation in human being?

Answer 1

The chemical process that generates most of the energy in the cell, supplying molecules needed to make the metabolic reactions of an organism run.

Double circulation system is usually found in complex organisms like us, humans. During a single cycle blood goes twice in the heart which is known as double circulation.

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Answer 2

cellular respiration is a set of metabolic reactions and processes that take place in the cells of organisms to convert biochemical energy from nutrients into adenosine triphosphate (ATP) , and than release waste products.

During a single cycle blood which is twice in the heart which is known as Double Circulation. It is necessary in human being to separate oxygenate and de-oxygenate blood because this makes their circulatory system is more efficient and helps in maintaining constant body temperature.