Food Webs & Food Chains

Systems

Types of Organisms

Environmental Factors

Other Key Terms

Ecosystem (ecological system)- a part of an environment which contains organisms and their interactions to the physical environment.

Energy Pyramid- a diagram that illustrates the transfer of energy through a food web or chain. As you go up the energy pyramid, the amount of energy available decreases.

Food Chain- an illustration of the relationship between a prey and predator (who eats what).

Food Web- a complex illustration showing more relationships between more organisms compared to a food chain.

Carnivores- heterotrophs that eat other animals.

Producers- also autotrophs, photosynthetic organisms that store the sun's energy during the process and provides food energy for a majority of living things.

Consumers- also heterotrophs, organisms that get a source of energy from eating other organisms.

Decomposers- organisms that consume dead organisms and their wastes. By doing this, decomposers recycle material that can be used by producers and thus restarts the cycle.

Herbivores- heterotrophs that eat plants.

Autotrophs- photosynthetic organisms that make their own food (self-feeders), also known as producers.

Heterotrophs- organisms that acquire energy from eating other organisms, also consumers.

Abiotic- nonliving influences in an ecosystem.

Predators- organisms that kill and eat other organisms.

Preys- organisms that are killed for food.

Biotic- living things in an ecosystem that interact with each other and the environment.

Carrying Capacity- the number of organisms of any single species that an ecosystem can support.

Competition- the struggle of resources among organisms.

Scavengers- consumers that eat dead organisms, known as clean-up organisms (NOT decomposers, who break down dead bodies and waste).

Limiting Factors- factors in the environment that limit the size of populations.

Environment- every living and nonliving thing that surrounds an organism.

Habitat- the specific environment that a species lives in, their home.

Population- all the organisms of a species that live in the same area.

Biosphere- all of Earth's ecosystems collectively.

Finite- limited.

Ecological Niche- the role that each species plays in an ecosystem.

Parasites- organisms that attack other live organisms although they rarely kill them. Parasites usually live on or in the body of their host and use them to live.

Hosts- Organisms that are being attacked by parasites and their body is being used by unintentionally providing a home for its parasite.