Answer:

1. The main source of food for deep-sea organisms comes from the epipelagic and mesopelagic zones in the form of waste and decaying organisms, which are collectively referred to as marine snow.
2. Organisms that only eat plants are called herbivores. Herbivores gets its energy from plants and will not eat any animals.
3. Secondary consumers are the animals that eat the primary consumers. They are heterotrophs, specifically carnivores and omnivores. Carnivores only eat other animals. Omnivores eat a combination of plants and animals.
4. The organisms that eat the secondary consumers are called tertiary consumers. These are carnivore-eating carnivores, like eagles or big fish. Some food chains have additional levels, such as quaternary consumers—carnivores that eat tertiary consumers. Organisms at the very top of a food chain are called apex consumers.
5. There are two types of food chains: the grazing food chain, beginning with autotrophs, and the detrital food chain, beginning with dead organic matter