How does the kube-proxy of a pod know what are the IPs of the other pods on real-time if they are changing all the time?

Basically that is my question:

How does the kube-proxy of a pod know what are the IPs of the other pods on real-time if they are changing all the time? That IPtable sounds kinda persistent, how does it get update if a pod cannot reach the Service IP and communicate with the IP?