Trace the flow of oxygen through an anesthetic machine and patient breathing circuit for rebreathing and non-rebreathing systems.
a) Oxygen flows from the machine to the patient and is then exhaled into the atmosphere in both systems.
b) Oxygen is recycled and rebreathed by the patient in a rebreathing system.
c) Oxygen flows from the patient to the machine and is replenished with fresh gas in a non-rebreathing system.
d) Oxygen flow is not necessary during anesthesia.