Mark has diabetes and needs to undergo dialysis twice a week . dialysis purrifies the blood by removing waste and excess water from the blood . which body system does dialysis perform a function for?

The procedure of dialysis maintains the body in balance by withdrawing waste, extra water, and salt by preventing them from accumulating up in the body when the kidneys fail. It helps in maintaining a safe level of some kinds of chemicals in the blood, like sodium, potassium, and bicarbonate. It helps in monitoring blood pressure.  

Hence, dialysis helps in performing a function for the circulatory system of the body.  

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