Final answer:
The process happening in the leading edge of migrating cells involves adhesion between moving surfaces.
Step-by-step explanation:
The process happening in the leading edge of migrating cells involves adhesion between moving surfaces. Adhesion occurs through the binding of molecules between surfaces that move relative to each other. This adhesion is particularly important for matrix adhesion underneath the cellular lamellipodium, where actin retrograde flow transports individual binding molecules from the cell edge towards the cell body to form and mature adhesions.