Autotrophs are organisms that can use inorganic compounds to make organic nutrients. Most carry on photosynthesis and a few carry on chemosyntheses. Heterotrophs are divided into groups depending on what they eat and how they obtain food. Herbivores eat plants. Carnivores eat other animals.
Predators kill and eat their prey.
Scavengers feed an dead animals. Omnivore seat both plants and animals. Saprophytes break down dead plants and animals. There are three types of symbiotic relationships that you will study in more detail later. Mutualism where both organisms benefit, commensalism where one organism benefits, and parasitism where the host may be killed by the parasite.