Final answer:
The enzyme with various isoenzymes necessitating electrophoretic separation to identify the source of activity is Alkaline Phosphatase (ALP), which is found in the liver, bone, and placental tissue.
Step-by-step explanation:
The enzyme in question, which is ubiquitous with a number of isoenzymes and requires electrophoretic separation of isoenzymes to locate the source of increased activity, is Alkaline Phosphatase (ALP). ALP is an enzyme in the cells lining the biliary ducts of the liver, and its levels in plasma will rise with bile duct obstruction, cholestasis, or infiltrative diseases of the liver. ALP is also present in bone and placental tissue, meaning it is higher in growing children and elderly patients with Paget's disease. Electrophoresis is necessary to differentiate between isoenzymes of ALP that may originate from the liver, bone, or other tissues, which is why it is of limited value in general clinical practice without isoenzyme analysis.