Tiny structures inside of cells such as ribosomes or chloroplasts that have specialized roles are called

Organelles

Explanation:

These structures are found in the cytoplasm of eukaryotic cells and are enclosed with a membrane.

because of

the relative standard reduction potential of the half-cell in which reduction occurs; more positive than the other half-cell. reduction is a chemical process in which electrons are added to an atom or an ion; it always occurs accompanied by oxidation of the reducing agent.