I really need help with this one

The prey population, the rabbits, and the predator population, the foxes, directly rely on one another. As the rabbit population grows, more food becomes available for the fox population to grow, therefore the fox population grows. The rabbit population now has more predators, but an assumed constant amount of food, causing the rabbit population to fall. The rabbit population falls and less food becomes available for the fox population, so the fox population falls. Both the predator and prey species are majorly responsible for the carrying capacities of the other species.

this protocol provides a detailed procedure for co-immunoprecipitation (co-ip) to identify protein–protein interactions.