Final Exam Review

Unit 3- Ecology

Environment

Every living and nonliving thing that surrounds an organism

Biotic Factors

• Living Factors• ex: plants, prey, predators,

bacteria, fungus

Abiotic Factors

• Nonliving Factors• ex: water, temperature,

sunlight, soil,

Population

A group of one species living in an area

CommunityAll of the different populations living in an area

EcosystemAll of the living and nonliving things and how

they interact in an area

BiomeGroup of ecosystems that have the same climate

and community

Habitat

Where an organism lives

Trophic Levels

AutotrophsOrganisms that produce

their own food for energy, photosynthesis

Ex: Producers: make their own food, through the process of photosynthesis, ex: plants, algae

HeterotrophsOrganisms that cannot produce their own food

for energy

Consumers: Organisms that eat/consume other organisms• Herbivore• Carnivore• Omnivore• Scavenger• Decomposer

Herbivoreeats plants, primary consumers, ex: deer, cow

Carnivoreeats meat/other consumers, ex: lion, tiger

Omnivore

eats both plants and animals, ex: humans, raccoons, bears

Scavengereats dead animals, ex: vultures

Decomposer

breaks down dead matter and recycles the nutrients back to the soil, ex: fungus, bacteria

Food Chainshows the flow of energy in an ecosystem,

simple

Food Web• many food

chains interconnected

• complex

Ecological Pyramids• Energy• Biomass• Numbers• decreases as you

move up the pyramid,

• producers are always the largest and on the bottom.

Biological Magnification

• The concentration of a toxin increases as is moves through the food chain, highest concentrations at the top of the food chain, ex:

• DDT in bald eagles

BiodiversityThe number of different species in an area, more

biodiversity=more stable

Niche

an organisms role/job in its environment, two species cannot occupy the same niche

Competitive Exclusion

When two organisms try to occupy the

same niche, they will compete. One will

stay in that niche and the other will either

die or have to occupy a different niche

The niche a species can ideally have, can be larger than the realized niche

Realized NicheThe niche a species actually occupies, can be smaller than the fundamental niche

Fundamental Niche

Niche Diversitythe number of different niches in an ecosystem due to abiotic factors• fluctuating abiotic factors many niches (desert)• constant abiotic factors=few niches (marsh)

Evolution

a slow gradual change in a species over time

Adaptation

A trait that an organism has that allows it to survive in a changing environment

Specialized species

• A species with a small niche, only one food source.

• Ex: koala bear and panda bear

Generalized species

• A species with a large niche, many food sources.

• Ex: mice, roaches

Convergent evolution

two species evolve separately to have similar traits because they have similar niches.

Coevolution

• When two species evolve to rely on each other for survival, mutualism

• ex: acacia tree and stinging ants

Predator-Prey

predator- the hunterprey-the hunted

Parasitismone organisms feeds off of another organism for survival, one species benefits, the other is harmed. Ex: tapeworm, malaria, ringworm– Host: The organism the parasite is feeding off of

Mutualism• two species rely on each other for survival,

both benefit• ex: Egyptian Plover and Nile Croccodile

CommensalismOne species benefits, the other isn’t harmed or

helped, ex: barnacles on a whale

Invasive SpeciesA non-native species that

causes harm to the environment

• Why are they dangerous? – They outcompete with

native species for essential resources

• How do they get here? – Accidental (in wood), boats

(mass transportation), intentional release (pets that get too big), tropical plants for garden

Endangered SpeciesA species that is close to extinction

Main reason for species endangerment? • Habitat destruction