AUTOTROPH An autotroph (or producer) is an organism that makes its own food from light energy or chemical energy without eating. Most green plants, many protists (one-celled organisms like slime molds) and most bacteria are autotrophs. Autotrophs are the base of the food chain.	CARNIVORE Carnivores are animals that eat meat. Carnivorous animals often have sharp teeth and powerful jaws.	CONSUMER A consumer is a living thing that eats other living things to survive. It cannot make its own food (unlike most plants, which are producers). Primary consumers eat producers, secondary consumers eat primary consumers, and so on. There are always many more primary consumers than secondary consumers, etc. (this is because energy is lost between each trophic level).	DECOMPSER A decomposer is an organism that breaks down organic matter. Some bacteria and fungi decomposers. What they leave behind is used by primary producers.
DETRIVORE A detrivore is an organism that feeds on detritus, dead and decomposing organisms. What they leave behind is used by decomposers. Vultures and crabs are detrivores.	ECOSYSTEM An ecosystem is an interacting group of living organisms in an area.	FOOD CHAIN A food chain is the sequence of who eats whom in a biological community (an ecosystem) to obtain nutrition. A food chain starts with plants or other autotrophs (organisms that make their own food from light and/or chemical energy) that are eaten by herbivores (plant-eaters). The herbivores are eaten by carnivores (meat-eaters). These are eaten by other carnivores. When any organism dies, it is eaten by dettrivores and then broken down by tiny microbes (detrivores) and the exchange of energy continues.	FOOD WEB A network of many food chains in an ecosystem is called a food web. Primary producers are he base of food web (they produce their own energy). Primary consumers eat primary producers. Secondary consumers eat primary consumers. Tertiary consumers eat secondary consumers. Quatenary consumers eat tertiary consumers.
HERBIVORE Herbivores are animals that eat plants. Herbivores are also called primary consumers. Most animals are herbivores.	HETEROTROPH A heterotroph (or consumer) is a living thing that eats other living things to survive. It cannot make its own food (unlike plants, which are autotrophs). Animals are heterotrophs.	OMNIVORE Omnivores are animals that eat both animals and plants. Some monivores include people, many monkeys and marmosets, lion tamarins, chimpanzees, and most bears.	PREDATOR A predator is an animal that hunts and kills other animals for food.
PRODUCER A producer (or autotroph) is an organism that makes its own food from light energy (using photosynthesis), or chemical energy (using chemosynthesis). Most green plants, many protists (one-celled organisms like slime molds) and most bacteria are producers. Producers are the base of the food chain.	TOP PREDATOR A top predator is an animal at the top of the food chain, like the jaguar or bald eagle. Top predators have little or no natural enemies.	TROPHIC LEVEL The trophic level of an organism is the position it holds in a food chain. Trophic level 1 is plants and other autotrophs (also called primary producers) - organisms at this level are also called primary producers. Trophic level 2 is herbivores (organisms that eat autotrophs) - organisms at this level are also called primary consumers. Trophic level 3 is predators that eat herbivores - organisms at this level are also called secondary consumers. Trophic level 4 is predators that eat secondary consumers - organisms at this level are also called tertiary consumers. Trophic level 5 is predators that eat tertiary consumers - organisms at this level are also called quaternary consumers. Decomposers (such as bacteria) start the cycle again.