AP®︎ Environmental Science: Unit 1 Flashcards

The living organisms in an area, the abiotic environment, and the interactions among them

A living or once-living biological component of an ecosystem

A nonliving physical or chemical component of an ecosystem, such as water, sunlight, temperature, or soil minerals

Individuals of the same species living in the same area

All populations of different species living and interacting in an area

The physical environment in which an organism lives and obtains the resources and conditions it needs

How a species uses resources, tolerates environmental conditions, and functions in relationships with other organisms

A resource whose limited availability restricts the growth, abundance, or distribution of an organism or population

A +/− interaction in which a predator captures and eats prey, benefiting while the prey is harmed and generally killed

A close, long-term interaction between individuals of two different species

A +/+ symbiotic interaction in which both species receive a net benefit

A +/0 symbiotic interaction in which one species benefits and the other is not significantly affected

A +/− symbiotic interaction in which a parasite obtains resources from a host and harms it without normally killing it immediately

A −/− interaction in which organisms require the same limited resource and each reduces the other's access to it

Competition among individuals of the same species

Competition between individuals of different species

Prolonged competition between species with nearly identical niches can prevent stable coexistence, with one species locally excluding the other

Competing species use shared resources in different ways, places, or times, reducing niche overlap and interspecific competition

A large land region characterized by climate and by plant and animal communities adapted to that climate

The long-term average pattern of temperature, precipitation, and other atmospheric conditions in a region

A graph showing average monthly temperature as a line and average monthly precipitation as bars for a location

Temperature generally decreases as latitude or altitude increases, causing similar biome changes from warm tropical systems toward colder temperate, boreal, and tundra systems

A high-northern-latitude biome with long cold winters, short summers, and forests dominated by evergreen conifers

A cool to moderate coastal biome with mild temperatures, abundant precipitation, and tall, dense forests often dominated by conifers

A biome with four seasons, moderate year-round precipitation, and broadleaf trees that shed their leaves before winter

A warm, wet equatorial biome with layered evergreen vegetation, exceptionally high biodiversity, and often highly leached, nutrient-poor soil

A Mediterranean-climate biome with hot dry summers, mild rainy winters, fire, and drought-resistant woody shrubs

A midlatitude interior biome with hot summers, cold winters, moderate to low precipitation, dominant grasses, and deep fertile soil

A warm tropical grassland with scattered trees, a distinct wet season, a long dry season, and frequent grazing and fire

An arid biome where precipitation is extremely low relative to water loss, producing sparse, drought-adapted vegetation

A treeless, very cold biome with low precipitation, a short growing season, low vegetation, and often permafrost

Ground that remains frozen for at least two consecutive years, restricting drainage, deep roots, and tree growth

Changes in temperature and precipitation can move biome boundaries as species ranges shift toward the poles, higher elevations, or other newly suitable areas

A low-salinity aquatic system, including streams, rivers, ponds, lakes, and freshwater wetlands, that provides vital drinking water

Bodies of flowing freshwater; streams generally carry less water than rivers, but no universal size boundary separates them

Bodies of standing freshwater; ponds are generally shallower, while lakes are generally larger and deeper

An inland area whose soil is covered or saturated by water for part of the year and supports water-tolerant vegetation

A saline aquatic system—including oceans, coral reefs, salt marshes, and estuaries—where algae take up atmospheric CO₂ and generate roughly half the oxygen produced by global photosynthesis

A partially enclosed coastal body of water where river freshwater mixes with seawater, creating productive brackish habitat

A tidal coastal wetland dominated by salt-tolerant grasses and other nonwoody emergent plants

A tropical or subtropical coastal wetland dominated by salt-tolerant trees and shrubs with dense root systems

A diverse marine ecosystem built by coral polyps in warm, shallow, clear, sunlit, saline water

The vast marine region beyond the continental shelf, whose sunlit surface often has low productivity because nutrients are scarce

The concentration of dissolved salts in water, commonly measured in parts per thousand (ppt)

The cloudiness of water caused by suspended particles, which reduces light penetration and may harm aquatic organisms

The portion of a body of water receiving enough sunlight for photosynthesis

Water below the photic zone that does not receive enough light to support photosynthesis

The shallow nearshore lake zone where sunlight reaches the bottom and rooted plants are abundant

The sunlit open-water lake zone away from shore, where phytoplankton are major producers

Deep lake water below the depth at which enough light is available for photosynthesis

The bottom surface and sediments of a body of water, inhabited by bottom-dwelling organisms

Marine algae remove atmospheric carbon dioxide through photosynthesis and release oxygen, producing roughly half of the oxygen generated by global photosynthesis

The repeated movement of matter between organisms and abiotic reservoirs such as air, water, soil, rocks, and sediments

A reservoir or process that releases more of a substance than it receives during a given period

A reservoir or process that receives and stores more of a substance than it releases during a given period

A location in which matter is stored for some length of time within a biogeochemical cycle

Movement of conserved carbon atoms and carbon-containing molecules among organisms, air, water, soils, sediments, rocks, and fossil fuels

Solar-powered transfer of inorganic carbon into producer biomass: 6CO₂ + 6H₂O + light → C₆H₁₂O₆ + 6O₂.

Breakdown of organic compounds that transfers carbon back to air or water as CO₂: C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + energy

Breakdown of dead organisms and waste that releases carbon through decomposer respiration or leaves some carbon stored in soil

Oxidation of carbon-containing material that releases CO₂; burning fossil fuels rapidly transfers geological carbon to the atmosphere

The capture and storage of carbon in biomass, soils, oceans, sediments, rocks, or other reservoirs

Relatively rapid carbon exchanges among the atmosphere, surface ocean, organisms, dead organic matter, and soil

Long-term carbon movement and storage through burial, deep-ocean processes, sediments, rocks, fossil fuels, and geological activity

Buried organic matter forms coal, petroleum, and natural gas over millions of years, and combustion rapidly transfers their stored geological carbon to the atmosphere as carbon dioxide

Movement and chemical transformation of nitrogen among the atmosphere, soil, water, and organisms; the atmosphere is its largest reservoir

Conversion of atmospheric N₂ into reactive nitrogen compounds; biologically, certain bacteria and archaea produce NH₃, which becomes NH₄⁺.

Uptake of ammonium or nitrate by producers and incorporation of its nitrogen into organic molecules and biomass

Decomposer conversion of organic nitrogen in wastes and dead matter into ammonia or ammonium

Microbial oxidation of ammonia or ammonium to nitrite and then nitrate, usually under oxygenated conditions

Microbial conversion of nitrate to gaseous N₂, often through N₂O, generally under low-oxygen conditions

Bacteria that convert atmospheric nitrogen gas into ammonia, which becomes ammonium usable within ecosystems

A nutrient whose low availability restricts biological growth; usable nitrogen often limits primary production

Movement of phosphorus among rocks, soil, water, organisms, and sediments through weathering, uptake, feeding, decomposition, runoff, sedimentation, rock formation, and uplift, with no significant atmospheric phase

A location where phosphorus is stored; the major long-term reservoirs are phosphorus-bearing rocks and ocean sediments

Weathering breaks down or alters rock in place and releases phosphate; erosion transports weathered, phosphorus-bearing material

Phosphorus has no significant gaseous phase and therefore cycles mainly through rocks, soil, water, organisms, and sediments

The continuous, sun-powered movement of water in solid, liquid, and gaseous phases among the atmosphere, oceans, surface water, soil, groundwater, ice, and organisms

The solar-powered conversion of liquid water to water vapor

The release of water vapor from plants, primarily through stomata in their leaves

The combined transfer of water vapor to the atmosphere through evaporation and plant transpiration

The conversion of water vapor to liquid water, producing cloud droplets as moist air cools

Water falling from the atmosphere to Earth’s surface as rain, snow, sleet, or hail

The entry of water from the ground surface into soil

The downward movement of water through soil and permeable rock after infiltration

Water that flows across the land surface toward streams, rivers, lakes, wetlands, and oceans

The slow movement of groundwater through pores and fractures in soil, sediment, and rock toward springs, streams, lakes, or oceans

A permeable underground layer of rock, sand, or gravel that stores and transmits usable groundwater

Rate at which producers convert solar energy into chemical energy stored in organic compounds, measured as energy per unit area per unit time

Total rate at which photosynthesis captures and stores energy in a given area before producer respiration is subtracted

Rate of energy storage as new producer biomass after respiration; NPP = GPP − producer respiration

Energy producers use in cellular respiration and therefore do not store as new biomass available to consumers

Light decreases with water depth because it is absorbed and scattered, limiting photosynthesis to the photic zone above the compensation depth

Most red light is absorbed within the upper 1 m, while blue light penetrates deepest but reaches beyond 100 m only in the clearest water

An organism’s feeding position in a pathway of energy and matter transfer, numbered upward from producers

An organism that makes organic compounds from inorganic materials and occupies the first trophic level

An organism that eats producers and occupies the second trophic level

An organism that eats primary consumers and occupies the third trophic level

An organism that eats secondary consumers and occupies the fourth trophic level in that feeding pathway

An organism that consumes animals and may occupy different consumer levels depending on its prey

An organism that consumes both producers and animals and can occupy more than one trophic level

An organism that ingests and fragments dead organic material and waste

An organism, especially a fungus or bacterium, that chemically breaks down organic matter and releases simpler substances

Energy requires continuous input, flows one way through trophic levels, and is ultimately dispersed as heat; matter is conserved and cycles between organisms and the environment

Atoms are neither created nor destroyed in ordinary ecosystem processes but are rearranged and transferred

A diagram with producers at the broad base and consumers in higher tiers, representing decreasing available energy at higher trophic levels

A diagram showing energy available at successive trophic levels, with an upright shape because each higher level contains less energy

About 10% of one trophic level’s energy passes to the next; after n transfers, Eₙ = E₀(0.10)ⁿ, where n counts transfers

The percentage of lower-level energy transferred upward: E_higher ÷ E_lower × 100

Energy cannot be created or destroyed, only transferred or transformed; energy lost from a trophic pathway is unavailable, not destroyed

Every energy transfer increases entropy and reduces energy available for useful work, with some energy becoming dispersed as heat

A simplified linear model showing one pathway of energy and matter transfer from a producer through successive consumers

A model of two or more interlocking food chains showing multiple pathways of energy and matter transfer in a community

An arrow ordinarily points from the organism being consumed to its consumer, the direction in which energy and matter are transferred

A series of indirect effects transmitted across multiple trophic levels after a population changes, often beginning with a top predator

A species whose effect on community structure and ecosystem function is disproportionately large relative to its abundance

A loop in which a system’s response reinforces the initial change, pushing the system farther in the same direction

A loop in which a system’s response counteracts the initial change and tends to promote relative stability