Basic Life Science Unit 1 Lecture Pages Chapter 12

Producers All energy that is used by living things comes from the sun Plants and algae use the sun’s energy to make their own food They are called producers

Consumers Most organisms cannot make their own food Instead, they get energy by eating other organisms These animals are called consumers They can be Herbivores Carnivores Omnivores

Herbivores Herbivores eat only plants Ex: rabbits, deer

Carnivores Carnivores are animals that eat only other animals They are meat eaters Ex: lions, hawks

Omnivores These animals eat plants and other animals Ex: humans, bears

Levels of Consumers At the bottom of the pyramid are the producers that use the sun to make their own food Then one level up are the animals that eat the producers They are the herbivores and are also called primary consumers Ex: caterpillars

The next level up are the animals that eat the herbivores and they are also called secondary consumers Ex: tree frogs

The next level up are the animals that eat the secondary consumers These animals are called tertiary consumers Ex: Toucans

Humans are primary, secondary, and tertiary consumers

Scavengers and Decomposers Animals that feed on dead animals are called scavengers Ex: vultures, hyenas Organisms that break down waste and remains of dead animals are called decomposers Ex: bacteria and fungi

Food Chains A food chain shows how the energy moves from one animal to another The food chain begins with the producers that use the sun to get their food Most food chains have about 5 steps

Each time an animal eats another one, less energy is available for the next step The most energy is available at the beginning of the chain

Food Webs A food web shows all the food choices animals have to eat. A food web is more complicated than a food chain

Energy Levels At the beginning of a food chain, there is 100% available. Each step on has 10% of that energy before it left to use. This is because animals use energy to grow and live. Lots of energy is lost into the atmosphere as heat

Energy Pyramid

Energy Pyramids The bottom of the energy pyramid is grass or algae usually. As you move up the pyramid into consumers, there is less energy available for the animals to use So there are not as many of these top animals