Answer:
Explanation: Natural selection is the process through which populations of living organisms adapt and change. Individuals in a population are naturally variable, meaning that they are all different in some ways. This variation means that some individuals have traits better suited to the environment than others.
It's called appendages if that is what you need
There are two approaches used when inserting a pacemaker; the epicardial approach and the transvenous approach. Epicardial approach involves the opening the chest cavity and placing a lead on epicardial sac of heart while the transvenous approach involves accessing a vein and inserting an electrode into the vein. Epicardial approach for inserting pacemakers are divided based on approach to heart thoracotomy, upper abdominal or endoscopic.