PART 1 INTERACTIONS - WE WILL LEARN THAT:

• Living things interact in a variety of ways to obtain materials needed for energy, growth, and repair.

• Plants are producers that manufacture their own food.

• In models or diagrams that depict the transfer of matter among organisms, arrows point downward in a direction that illustrates what eats what.

• In models or diagrams that depict energy transfer among organisms, arrows point upward toward the organisms to whom energy is being transferred.

• All animals are consumers that obtain food by eating other organisms or their products.

• Some consumers eat other animals; other animals consume both plants and animals.

• Some animals eat only plants, some eat only animals, and other animals consume both plant and animals.

• Decomposers, such as bacteria and fungi, obtain food from the breakdown of dead plants or animals.

• Scavengers depend on dead or decaying material from plants and animals for food.

• Organisms interact with one another in additional ways besides providing food.

• Interactions among organisms can have positive or negative outcomes on one and/or the other.

• Predators have a negative effect on their prey since they capture and feed upon them.

• Parasites have a negative effect on the hosts upon or within which they live, feed, and sometimes reproduce.

• Some relationships among species are mutually beneficial.

• Some species have become so adapted to each other that neither can survive without the other.

FOCUS QUESTIONS:

• Why must organisms interact with other organisms?

• How are organisms categorized in terms of their basic food source?

• What are the different types of positive and negative interactions among species?