Unit 4 Vocabulary

Term

Definition

Ecology

Study of the interactions btwn organisms & their environments

Organism

Single member of a specific species

Species

Group of organisms able to successfully interbreed & create fertile offspring

Population

All members of a species within a specific location

Community

All populations interacting within a specific location

Ecosystem

A specific location in which both biotic & abiotic (nonliving) factors interact 

Biome

Large geographic area characterized by specific kinds of plants,animals, climate

Competition

Struggle for limited resources- interspecific or intraspecific

Interspecific

Between members of different species

Intraspecific

Between members of same species

Biotic

Living, biological factors

Abiotic

Physical, non living factors- ex. Soil, water, air, nutrients

Symbiosis

A close interaction btwn 2 organisms in which at least 1 benefits

Mutualism

Both organisms benefit in the relationship ex. Cape buffalo & Egret

Commensalism

1 organism benefits, the other is unharmed ex. Clownfish & Sea Anemone

Parasitism

1 organism benefits & the other loses energy/harmed ex. Tapeworm & gut of Human 

Interdependence

Idea that all [non]living things in an ecosystem depend on each other to survive/function

Tolerance Curve

A graph that represents the success of species vs. a specific abiotic factor

Optimal Range

The variation in a factor that allows for population growth

Zone of Intolerance

The extreme range of a factor that prevents population growth; the population is at risk of eradication

Zone of Stress

Range of a factor where population growth equals death; the population is at risk of eradication

Coping Mechanisms

Strategies used by organism to overcome abiotic factors (increase their optimal range)

Dormancy

State of reduced activity during periods of unfavorable environmental conditions

Migration

Move temporarily to a more favorable environment ex. Loon migration to ocean to avoid low temps & scarce food

Acclimation

Ability to adjust to abiotic factors over time ex. Increasing fat reserves & coat density by bears in winter

Metabolic Strategies

Organisms utilize 2 basic strategies when interacting w/ the nonliving environment, especially temperature

Conformers

Organisms that do not regulate their interior environment, they change as their external environment changes

Regulators

Use energy to control internal conditions, maintain homeostasis despite changes in the environment

Niche

Role of an organism within an ecosystem determined by its environment, biotic & abiotic factors. An organism's “job” in its ecosystem ex. Arboreal mammals- live, nest & find food in trees & don’t usually come to forest floor (squirrels, monkeys)

Habitat

Location where an organism lives, ex intertidal zone, tree canopy

Generalists

Species who can occupy a very broad niche; tolerates a wide range of conditions & uses a variety of resources ex. Opossum, leopard

Specialists

Species who occupy a very narrow niche ex. Pandas only live in a very tiny area of mountainous China w/ a very particular bamboo as food

Trophic Levels

Specific roles defined by nutrient/energy attainment

Producers

Autotrophs, manufacture their own food using photosynthesis ex. Plants, algae, lichens, photosynthetic bacteria

Consumers (primary, secondary, tertiary)

heterotrophs , cannot manufacture their own food, must ingest other organism

Primary- (herbivore) organisms that only eat producers

Secondary- organism that eat other consumers

Tertiary- must be a carnivore

Omnivore

Will eat both producers & consumers

Carnivore

Eats only other consumers

Scavenger

Will eat organisms that have recently died

Decomposer

Organisms that break down dead organic tissues & organic matter ex. fungi, worms, bacteria

Food Chain

Sequence of energy transfer w/in an ecosystem beginning w/ a producer-> single pathway of energy flow, arrows indicate direction of flow

Food Web

Interlinked food chains; complex energy pathway

10% Rule

only 10% of energy at a trophic level is passed onto the next level, remainder is lost as heat or in solid wastes

Ecological Pyramid

Diagram showing the changes in available energy, # of organism, or biomass in an ecosystem

Keystone Species

An organism in an ecosystem that has a critical role in the success & survival of the ecosystem & all other organisms present ex. Sea otters, starfish

Trophic Cascade

When an organism (usually keystone species) is removed from ecosystem/food chain-> causes next lowest trophic level to grow in pop. -> causes next lowest trophic level to decrease in pop & ecosystem to collapse

Terrestrial Succession (primary, secondary)

Changes in an ecosystem as it ages & matures

Primary- development of a community where one hadn’t existed previously; soil forms first then plant community resets

Secondary- recovery of an ecosystem after complete or partial destruction; soil remains but plant community resets ex. Forest fire, hurricane damage

Pioneer organism

First organism to become established in a once=barren area; small, fast growing fast reproducing ex. Lichen on rock

Climax community

Final stable stage of succession, “old growth forest”-> have many dif age/species of trees, as old trees die, new species/ages of plants occur

Seral community

Interim stages that an area goes through as it establishes a climax community, all westford foresta are examples- westford has been deforested mult. times 

Eutrophication

The aging of a freshwater pond/lake

Usually takes hundreds of years, however long it takes, all lakes will fill w/ sediment & become a forest in time->is sped up by synthetic fertilizers, dams & deforestation

Ex. stony brook river->dams slowed water flow & sediment collected/algae formed

Oligotrophic

Few plants, high clarity, firm bottom, high dissolved oxygen levels

Species- trout,salmon, insects

Mesotrophic

Moderate amount of plants, mod clarity, mod dissolved oxygen levels ex. Forge pond

Species- bass, sunfish, perch, ducks

Eutrophic

Abundant plants, poor clarity, mucky bottom, low dissolved oxygen levels ex. Grassy pond

Species- catfish, snapping turtles, herons

Cultural Eutrophication

Introduction of pollution/foreign materials & chemicals into bodies of water->causes rapid overgrowth of plants->eventually causes ecosystem to collapse

Cause- humans/human activity

Result- hypoxic (low oxygen) or dead zone