APES Unit 1.1 Ecosystems

Individual

One single organism (e.g., an elk) Population

individuals of the same species living in an area Community

All living

organisms in a given area Ecosystem

All living (biotic) and nonliving

(abiotic) things in an area Biome

The plants and animals found in a given

region, determined by climate (annual temperature and precipitation) Mutualism

A symbiotic relationship that benefits both organisms (+/+) Commensalism

A

symbiotic relationship that benefits one organism and doesn't impact the other

(+/0) Parasitism

A relationship where one organism uses a host for energy,

often without killing the host (+/-) Competition

Organisms fighting over a

shared, limited resource like food or shelter Resource Partitioning

Different

species using the same resource in different ways, places, or times to reduce

competition Temporal Partitioning

Using a shared resource at different times

(e.g., hunting at night vs. day) Spatial Partitioning

Using different areas of

a shared habitat to reduce competition (e.g., plant roots of different lengths)

Morphological Partitioning

Using different resources based on different

evolved body features Herbivores

Plant eaters that consume plants for energy

True Predators

Carnivores that kill and eat prey for energy Parasitoids

Organisms that lay eggs inside a host; eggs hatch and larvae eat the host for

energy Littoral Zone

Shallow water area of a lake with emergent plants

Limnetic Zone

Open water area of a lake where light can reach for

photosynthesis; contains no rooted plants, only phytoplankton Profundal Zone

Deep water area of a lake where sunlight cannot reach (no photosynthesis)

Benthic Zone

The murky bottom of a lake where invertebrates live in

nutrient-rich sediments Wetland

An area with soil submerged or saturated in

water for at least part of the year, shallow enough for emergent plants Estuary

An area where rivers empty into the ocean, creating a highly productive mix of

fresh and salt water Photic Zone

The upper layer of the open ocean where

sunlight can reach for photosynthesis Aphotic Zone

The deep layer of the ocean

(abyssal zone) that is too deep for sunlight Carbon Sink

A reservoir that

takes in more carbon than it releases (e.g., ocean, plants, soil) Carbon Source

A reservoir that releases more carbon than it takes in (e.g., fossil fuel

combustion, deforestation) Photosynthesis

Process by which plants and algae

remove CO2 from the atmosphere and convert it to glucose Cellular Respiration

Process done by living organisms that uses O2 to break down glucose and release

energy, emitting CO2 Ocean Acidification

Increased acidity of ocean water

caused by increasing atmospheric CO2 directly dissolving into the ocean Burial

(Carbon Cycle)

A slow, geological process that stores carbon in underground

sinks like sedimentary rock or fossil fuels Nitrogen Fixation

The process of

N2 gas being converted into biologically available forms (useable by plants)

like ammonia (NH3) or nitrate (NO3-) Assimilation

Plants and animals taking in

nutrients (like nitrogen or phosphorus) and incorporating them into their body

tissues Ammonification

Soil bacteria and decomposers converting waste and dead

biomass back into NH3 and returning it to soil Nitrification

The conversion of

ammonium (NH4) into nitrite (NO2-) and then nitrate (NO3-) by soil bacteria

Denitrification

The conversion of soil nitrate (NO3-) into nitrous oxide (N2O)

gas, which returns to the atmosphere Leaching

Nutrients (like nitrates from

synthetic fertilizers) being washed or carried out of the soil by water

Eutrophication

A process where excess nutrients (nitrogen and phosphorus) in

aquatic ecosystems fuel algae blooms that block sunlight and deplete oxygen

Weathering

The breakdown of rock by wind and rain; the major natural source of

phosphorus in the environment Geological Uplift

Tectonic plate collisions

forcing up rock layers to form mountains, restarting the phosphorus cycle

Transpiration

The process plants use to draw groundwater from roots up to

their leaves, where it evaporates into the atmosphere Evapotranspiration

The

total amount of water that enters the atmosphere from plant transpiration and

surface evaporation combined Infiltration

Precipitation trickling through

permeable soil down into groundwater aquifers Primary Productivity

The rate at

which solar energy is converted into organic compounds via photosynthesis over a

unit of time Gross Primary Productivity (GPP)

The total amount of sun energy

that plants capture and convert to glucose through photosynthesis Net Primary

Productivity (NPP)

The amount of energy (biomass) leftover for consumers after

plants have used some for their own respiration (NPP = GPP - Respiration Loss)

Respiration Loss (RL)

The energy plants use up from their own photosynthesis

by doing cellular respiration 1st Law of Thermodynamics

Energy is never

created or destroyed; it only changes forms 2nd Law of Thermodynamics

Each

time energy is transferred, some of it is lost as heat, decreasing the amount of

useable energy 10% Rule

In trophic pyramids, only about 10% of the energy or

biomass from one level makes it to the next level (the rest is used or lost as

heat) Producers

Organisms (plants) that convert the sun's light energy into

chemical energy Primary Consumers

Animals that eat plants (herbivores)

Secondary Consumers

Animals that eat primary consumers (carnivores and

omnivores) Tertiary Consumers

Animals that eat secondary consumers (top/apex

predators) Food Web

A model showing at least 2 different, interconnected food

chains that depicts how matter and energy flow through an ecosystem Trophic

Cascade

The ripple effect down through lower trophic levels that occurs when a

top predator is removed from or added to an ecosystem