Elisa feels tired because she has a condition that affects whether the right molecules are getting to her cells. If her body were functioning correctly, this is what would happen with oxygen

The oxygen is available in a right amount.

Explanation:

The oxygen is available in a right amount because her body were functioning correctly and we know that our body functioning correctly if it gets oxygen in a right amount otherwise body will not perform correctly its functions. The tiredness Elisa feels is due to her routine work which can be eliminated by doing rest for sometime so after resting sometime she feel better and active.

Elsie has the right amount of oxygen needed by the cells if her body were

functioning correctly.

Oxygen is an important in the body's metabolic processes and help in the

metabolism of glucose to energy which is needed by all the cells of the

body. When the oxygen is deficient , the blood won't be able to pump

oxygen through the blood to body cells.

This then results in decreased cell functions and metabolism thereby causing tiredness , cell damage and death if severe.

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ecotourism pay for conservation efforts.

a scenario where a cell may be needed to perform a form of endocytosis is when transporting large molecules. a scenario where a cell may be needed to perform a form of exocytosis is when releasing the large molecule from the cell.