Ecology & the Environment Life Science Ecology & the Environment

Ecology Study of the interactions that take place among organisms and their environment.

Biotic Living parts of the environment; plants animals & microorganisms

Abiotic Non-living parts of the environment; water, air, light, rocks

Consumer  Organism that cannot create energy-rich molecules (glucose) but obtains its food by eating other organisms

Producer An organism, such as a plant or alga, which produces glucose from carbon dioxide by photosynthesis and is a source of food for other organisms

Carnivore Animals who hunt and eat other animals; meat eater

Omnivore An organism that eats both plants and animals

Herbivore An animal that eats plants

Food Chain The relationship between plants and animals that shows who eats what. Energy is transferred from one organism to another through the food chain

Food Web A model of feeding relationships, describing the connections among all food chains within an ecosystem

Energy Pyramid A representation of the loss of useful energy at each step in a food chain

Pyramid of Numbers Based on the number of organisms needed to make a simple food chain. Shows how large populations of certain organisms are needed to support very small populations of other organisms.

Symbiosis An interactive association between two or more species living together; may be parasitic, commensal, or mutualistic. The relationship between two organisms

Commensalism A symbiotic relationship in which one species benefits and the other is not affected

Parasitism A form of symbiosis in which the population of one species benefits at the expense of the population of another species

Mutualism A symbiotic interaction between two species in which both derive some benefit

Competition One of the biological interactions that can limit population growth; occurs when two species vie with each other for the same resource

Population All the organisms that belong to the same species living in a community

Community All the populations of different species that live in an ecosystem

Habitat Place where an organism lives and that provides the types of food, shelter, moisture, and temperature needed for survival

Niche An organism’s place in the ecosystem: where it lives, what it consumes, what consumes it, and how it interacts with all biotic and abiotic factors. A unique ecological role of an organism in a community.

Organism Any living thing

Biosphere Part of Earth that supports life, including the top portion of Earth's crust, the atmosphere, and all the water on Earth's surface

Ecosystem All the living organisms that live in an area and the nonliving features of their environment

Limiting Factor Anything that can restrict the size of a population, including living and nonliving features of an ecosystem, such as predators or drought

Carrying Capacity Largest number of individuals of a particular species that an ecosystem can support over time

Biotic Potential The maximum reproductive rate of an organism, given unlimited resources and ideal environmental conditions

Exponential Growth Growth of a population without any constraints; therefore, the population will grow at an ever-increasing rate

Photosynthesis The chemical reaction in which green plants combine water and carbon dioxide in the presence of sunlight to form glucose and oxygen

Predator An animal that kills and eats other animals

Prey An animal that is killed and eaten by another animal