Biology 1 Honors Ecology

Flashcards on Ecology

Ecology

The study of interactions of organisms with each other and their physical surroundings.

Biosphere

Part of the Earth where life exists.

Ecosystem

Given physical areas (abiotic) and the living organisms that inhabit that area (biotic).

Communities

Collective terms for all species living in one ecosystem.

Weather

The day to day conditions of the Earth’s atmosphere in a given year.

Climate

Refers to the average year-to-year conditions of temperature and precipitation.

Greenhouse Effect

Gases in the atmosphere such as carbon dioxide (CO2), methane (CH4), and water vapor (H2O) that trap heat.

Nutrients

Elements needed to grow and build molecules such as nitrogen.

Producers

Capture energy from the sun (such as photosynthetic algae or phytoplankton) or another inorganic source like chemosynthetic bacteria.

Primary consumers

Feed on the producers.

Secondary consumers

Feed on the primary consumers.

Tertiary consumers

Feed on secondary consumers, etc.

Decomposers

Break down dead organisms (bacteria and fungi).

Herbivores

Eat plants.

Carnivores

Eat animals.

Omnivores

Eat both plants and animals.

Detritivores

Eat dead organic matter; detritus such as crabs, mites, earthworms.

Keystone species

An organism that helps define an entire ecosystem; without it, an ecosystem would be dramatically different or ceases to exist

Biomass

The total mass of organisms at one trophic level.

10% Rule

When energy is passed from one trophic level to the next, only 10% (on average) of the energy will be passed on.

Biomagnification

Refers to the increase in concentration of a substance (such as a pesticide) in the tissues of organisms at successively higher levels in a food chain.

Ecological Succession

Start of a new community.

Primary Succession

No life before.

Secondary Succession

One community replaces another.

Pioneer species

Those organisms that begin to colonize areas that did not have living things before (they start 1° succession).

Climax community

A stable collection of organisms in an area.

Primary productivity

The rate at which organic matter is created by producers

Limiting nutrients

Substances that limit the primary productivity; often nitrogen or phosphorus.

Biomes

Environments that have a characteristic set of climate conditions.

Tundra

Northernmost (Arctic) biome; almost treeless; lichens, moss, grass; permafrost layer from year to year stunts plant growth

Chaparral

Vegetation adapted to periodic fires, most often caused by lightning.

Taiga or Boreal Forest

Forests like conifers, pines, furs, spruce South of tundra

Temperate Deciduous Forest

Forests of oak, maple Eastern coast of US and most of Europe

Temperate Grasslands

Grasses and small leafy plants Interior of most continents

Savanna- Tropical Grasslands

More variation of wet/dry seasons than grasslands; periodic fires and lots of grazing, preventing succession

Tropical Rain Forests

Warm temperatures (25 °C) and consistent rainfall year round; large diversity in organisms; but nutrient poor soils

Desert

Less than 25 cm of rain per year; can be hot or cold; Sahara is the largest desert in the world

Freshwater Aquatic Biomes

3% of all surface water; Rivers, streams, and lakes; provides much of our drinking water and food

Marine Aquatic Biomes

Cover most of the Earth’s surface; can be divided into vertical and horizontal zones

Photic zone

Zone where light can penetrate; allows phytoplankton and algae to grow; depth varies from 30-200 meters

Aphotic zone

Zone where no light penetrates

Intertidal Zones

Radical daily changes in environment as tide moves in and out

Neritic Zone (Coastal Ocean)

Extends from low tide line to open sea; falls in photic zone so lots of algae, seaweed, and fish; lots of nutrients

Open Sea

Phytoplankton responsible for most photosynthesis; many fish and mammals; nutrients scarce and limits number of organisms that can grow

Deep Sea Zone, or Benthic Zone

Attached or near the bottom; high pressure, cold temperatures and no sunlight; many detritivores

Coral Reefs

Warm, shallow, tropical waters; corals are tiny animals that secrete hard calcium rich exterior; their small tentacles capture food; need warm, salty water

Estuaries

Boundaries of fresh and saltwater; shallow - much photosynthesis; allows much plant life and variety of animals; lots of available nutrients

Salt marshes

Temperate zone and dominated by salt tolerant grasses above water level and sea grass underwater – Ex: Chesapeake Bay area