Describe how
ions impact functions
in the heart

Explanation:

In a normal heart, there is a balance between calcium and potassium ion levels in both the outer and inner walls of the heart. That balance keeps electrical energy flowing correctly through the heart, and allows the heart muscle to expand and contract as the heart beats.10-Nov-2005

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a boiling water reactor does not boil the water. a pressurized water reactor boils the water faster. a pressurized water reactor is heated directly by the core. a pressurized water reactor does not use fission.

a corroding iron, if that's one of your choices