Final Unit 3

Ecosystem

A biological community of interacting organisms and their physical environment.

Energy

The qualitative property that must be transferred to an object to perform work on, or heat the object.

Photosynthesis

The process of using light energy to convert carbon dioxide (inorganic carbon) to carbohydrates (organic carbon).

Cellular respiration

The process of breaking down the chemical bonds in food molecules (organic carbon) to harvest energy and release carbon dioxide (inorganic carbon).

Food chain

A hierarchical series of organisms, each dependent on the lower level as a source of food.

Primary producers

Organisms at the 1st trophic level that transform energy from the sun.

Primary consumers

Herbivores that make up the 2nd trophic level of a food chain.

Secondary consumers

Predators (carnivores) that make up the 3rd trophic level of a food chain.

Tertiary consumers

Predators (carnivores) that make up the 4th trophic level of a food chain.

Decomposers

Organisms that feed on nonliving organic matter, such as feces and dead organisms.

Food web

The natural interconnection of food chains, representing what eats what in an ecological community.

Keystone species

Species whose removal causes a collapse in the ecosystem.

Matter

Any substance that has mass and takes up space by having volume.

Carbon Cycle

The planet-wide flux of carbon driven by life processes.

Nitrogen fixation

The conversion of N2 gas into ammonia (NH3) by bacteria and lightning.

Nitrification

The process where NH3 is converted to nitrite (NO2-) and then to nitrate (NO3-) by bacteria.

Denitrification

The process where nitrates are converted back to nitrogen gas and returned to the atmosphere by bacteria.

Phosphorus Cycle

The cycle involving the dissolution of phosphorus in soil and water, and its absorption by plants.

Biome

A large naturally occurring biological community of flora and fauna occupying a major habitat.

Convergent evolution

The process where unrelated species independently evolve similar traits due to adapting to similar environments.

Tropical rainforest

A biome with annual rainfall greater than 2,000 mm and enormous plant and animal diversity.

Endemic species

Species that are found only in specific environments and geographic areas.

Biodiversity

The variety of life in all its forms and combinations at all levels of organization.

Species richness

The total number of species in an area.

Species evenness

The relative abundance of the species in a community.

Genetic diversity

The genetic variation among individuals, which allows for natural selection.

Outbreeding

Mating with nonrelated individuals to maximize diversity and adaptation.

Inbreeding

Mating between closely related individuals.

Fire suppression paradox

The practice of fire suppression can lead to increased wildfire risk and severity due to fuel buildup.

Climate change

Long-term shifts in temperatures and weather patterns.

Habitat fragmentation

The process of dividing large areas of habitat into smaller, isolated pieces.

Non-native invasive species

Introduced species that cause harm to the environment.