A negative feedback loop is a reaction that causes a decrease in function. It occurs in response to some kind of stimulus. Often, it causes the output of a system to be lessened; so, the feedback tends to stabilize the system. This can be referred to as homeostasis, as in biology, or equilibrium, as in mechanics.
Plankton is the organisms that form the base of most open ocean food webs because fish eat plankton and bigger fish like sharks eat the little fish that eats the plankton.
