At the begining of the ocean food chain, are the smallest, but one of the most important plants in the food chain. They are called Phytoplankton (FI-to-plank-TON). They are the base of the ocean food chain. Without them, most of the sea animals would not get food. Things like seatars, shrimp, and snails all eat phtoplankton. these animals just listed are ussually prey. If there was no phytoplankton, those animals would not have food, and eventually die out. Without the animals that eat the plankton, their preditors wouldn't get food, and they would die out, without them, their preditors will die out, and so on.