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

NicheAn 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