Electrical stimulation of cells is and electrical relaxation of cells is .

Electrical stimulation of the cell is depolarization, and electrical relaxation of cells is repolarization.

Explanation:

The electrical activity of the cell depends on the charges distributed on each side of its membrane, which depends on the presence of ions on each side, extracellular sodium and intracellular potassium.

A cell, like the neuron, at rest has a tendency to be negatively charged in its cytoplasm, while the extracellular space has a positive charge.

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enzyme active site and substrate specificity

enzymes bind with chemical reactants called substrates. there may be one or more substrates for each type of enzyme, depending on the particular chemical reaction. in some reactions, a single-reactant substrate is broken down into multiple products