Answer:
Because the mass contributed by electrons is dwarfed by the nuclear contribution. There exists three orders of magnitude difference. Electronic mass can be ignored to a first approximation.
Explanation:
Skeletal muscle: multinucleated, striated; attached to bones producing locomotion, general support and posture; producing heat. Contraction is voluntary, and not long-sustained. b. Cardiac muscle: found only in the heart and responsible for contraction of cardiac tissue and distribution of blood.
