IV. Roles of Living Things

A. Producers 1. Producers are organisms that make their own food. 2. Main source is photosynthesis a. CO2 + H2O ---CH2O + O2 3. Some bacteria are producers by do not use photosynthesis a. Use thermal vents and sulfur

B. Consumers 1. Any organism that must take in energy 2. Animals, fungi, protists, and bacteria 3. One of four types a. Herbivores- eat producers, called primary consumers

b. Carnivores- eat primary. consumers called secondary b. Carnivores- eat primary consumers called secondary consumers; eat secondary consumers called tertiary consumers c. Omnivores- eat whatever d. Scavengers- feed on dead, start process of returning nutrients

C. Decomposers 1. Organisms that consume dead bodies or organic waste 2. Bacteria, fungi, and some insects 3. Responsible for nutrient cycling 4. If they disappear, everything dies