The Predators really have the complete upper hand. The predators eat the pray: fathers, mothers, babies. This stops the family tree and lowers the population. IF the Prays population lowers then the predators populations would go down too because they depend on the pray as there food source.
Since predators need to eat prey, they keep the prey from over populating the area and of there are less prey to eat, there will be less predators ( at least in that area, some might move somewhere else where there's more food)
There are two types of bone marrow: red and yellow. Red marrow contains blood stem cells that can become red blood cells, white blood cells, or platelets. Yellow marrow is made mostly of fat.
Any molecule that is small enough to fit through can pass through the cell membrane. Other larger cells must pass through specialized protein channels that allow only specific molecules through.