The study of ecosystems or how organisms interact with each other and their environment.

Ecology

Largest level or organization. The zone of life on earth that includes all living things.

Biosphere

A group of the same species of individuals living in the same area and interacting with each other in some way.

Population

Populations of different species that live in a specific location.

Community

A community or group of organisms living and interacting with other and their environment (non living factors)

Ecosystem

Unchecked reproduction of a population of organisms. Occurs when each individual in a population reproduces, the offspring reproduce, and then the offpring of the offspring reproduce.

Exponential Growth

The largest population that a given ecosystem can support at any time. It is determined by the availability of resources.

Carrying Capacity

Living things or things associated with or the result from the activities of living organisms in an ecosystem.

Biotic Factors

Nonliving thing in an ecosystem such as rocks, soil, climate, etc.

Abiotic Factors

A producing or feeding level in a food chain.

Trophic Level

1st trophic level in organization. Plants and other photosynthetic organisms that produce glucose (converts sun energy into chemical energy). Also known as autotroph.

Producer

The pathway along with food/energy is transferred from one organism to another.

Food Chain

Shows flow of energy in all of the interconnected food chains in an ecosystem.

Food Web

An organism that eats other organisms or are heterotrophs.

• Primary consumer - herbivores, eats producers
• Secondary consumer - eats primary consumers
• Tertiary consumer - eats secondary consumer

Consumer

Species that plays a key role in maintaining ecosystem stability.

Keystone Species

A large area dominated by characteristic plants and animals, such as a rain forest, desert, or tundra. Determined by participation and temperature. It is the broadest level of ecological classification within the biosphere.

Biome

The variety of species and total number of individuals of each of species living in a defined area. An important indicator in how healthy and well-functioning an ecosystem is.

Biodiversity

Limits the potential for a population to grow exponentially due to the availability of resources such as food, water and predators.

Limiting Factors

Organisms that eat other organisms for energy. Also known as consumers.

Heterotroph

Organisms that produces its own food either by photosynthesis or chemosynthesis. Also known as a producer.

Autotroph

An ecosystem in water - can be marine (saltwater) or freshwater ecosystems.

Aquatic Ecosystem

Ecosystem found on land. 6 main types:

• Tundra
• Taiga
• Temperate Deciduous forest
• Tropical Rain Forest
• Grassland
• Desert

Terrestrial Ecosystem

A graphical model that is shaped like a pyramid to show how the energy flows through a food chain.

Ecological Pyramid

A graphical representation of the total amount of chemical energy present at each trophic level of an ecosystem.

Energy Pyramid

Used to explain energy flow in energy pyramids. In each trophic level, 90% of the available energy is used by that level and 10% moves up to the next level when they are eaten.

10% rule

The change in species composition in a defined area over time, starting on ground that has no living things on it.

Primary Succession

First plants or animals to inhibit bare land.

Pioneer Species

When ecosystems change over time through the progressive replacement of species.

Succession

Changes in plant and animals life in an established ecosystem, can only occur after an ecosystem is in place.

Secondary Succession

A stable, long-lasting community that results from succession.

Climax Community

Organisms that have invaded established ecosystems and disturbs the balance of the ecosystems. Also known as invasive species.

Non native species

How water is stored and moved between land, air, and living things.

Water Cycle

Part of water cycle where water vapor condenses into liquid water by clinging to dust or other small particles suspended in the atmosphere, forming clouds

Condensation

Part of the water cycle where liquid water changes to water vapor due to heat from the sun.

Evaporation

Part of the water cycle where a plant loses water to the atmosphere through the surface of its leaves.

Transpiration

Processes in which organisms exchanges gases with its environment. Part of the water cycle because animals exhale water vapor into the air during respiration.

Respiration

Organisms, such as bacteria and fungi, that consume very small bits of organic matter from dead organisms and breaks them down into chemicals that are recycled back into the environment.

Decomposer

The relationship between two different kinds of living things that live together and depend on each other. Three kinds:

• Mutalistic
• Parasitic
• Commensalistic

Symbiosis

Type of symbiosis where both organisms in the relationship benefit.

Mutalism

Type of symbiosis where one organism benefits (parasite) at the expense of the other (host).

Parasitism

Type of symbiosis where one organism benefits and the other is not affected.

Commensalism

Cycle where nitrogen changes into different chemical forms. Atmosphere is largest reservoir of nitrogen, but is not useable so it needs to be converted into useable forms for organism.

Nitrogen Cycle

Conversion of nitrogen gas into ammonia and nitrates by bacteria. Bacteria form symbiotic relationship with plants to provide usable nitrogen for plants.

Nitrogen Fixing

The conversion of nitrate to gaseous nitrogen by bacteria, which then enters the atmosphere. These bacteria use nitrogen compounds instead of oxygen for their processes of respiration.

Denitrification

Processes that recycle carbon, one of the most important elements on earth, between earth's soil, atmosphere, and organisms.

Carbon Cycle

Processes that cycle of oxygen between air, land, and organisms.

Oxygen Cycle

Resources that regenerate or regrow fast enough for us to keep using them. Ex: radiant energy, livestock, wind and water.

Renewable Resources

Resources which either cannot be renewed at all or take such a long time to renew that people cannot depend on the renewal. Ex: oil and fossil fuels.

Nonrenewable Resources

The process in which the atmosphere reflects radiation bouncing off earth's surface.

Greenhouse Effect

Gasses in the atmosphere which trap radiant energy, such as carbon dioxide. Increased greenhouse gases are thought to be causing global warming.

Greenhouse gases

The presence of harmful materials in the environment.

Pollution

An interaction between organisms or species, in which fitness of one is lowered by the presence of another

Competition

Where a predator feeds on a prey. Population size of the predator affect the population size of the prey and vise versa.

Predation