Chapter 4

Question 1

Competition

Answer 1

when organisms seek the same resource; negative interaction

Question 2

Intraspecific competition

Answer 2

competition between members of the same species

Question 3

Interspecific competition

Answer 3

competition between members of different species

Question 4

Resource partitioning

Answer 4

individuals use shared resources in different ways

Question 5

Predation

Answer 5

process by which individuals of one species kill and eat individuals of another

Question 6

Parasitism

Answer 6

organism depends on another for nourishment, usually not resulting in death

Question 7

Pathogens

Answer 7

parasites that cause disease, including protists, bacteria, and viruses

Question 8

Coevolution

Answer 8

parasites and hosts adapt/counter-adapt to each other

Question 9

Evolutionary arms race

Answer 9

duel of escalating adaptations between parasites and hosts

Question 10

Herbivory

Answer 10

animals feed on plant tissue (e.g. insects)

Question 11

Mutualism

Answer 11

two or more species benefit each other

Question 12

Symbiosis

Answer 12

close physical association between species

Question 13

Pollination

Answer 13

relationships which require free-living organisms to encounter each other once

Question 14

Community

Answer 14

assemblage of populations of organisms living in the same area at the same time

Question 15

Trophic level

Answer 15

rank in the feeding hierarchy

Question 16

Producers/autotrophs

Answer 16

use photosynthesis/chemosynthesis to make their own sugars

Question 17

Primary consumers

Answer 17

consume producers

Question 18

Secondary consumers

Answer 18

consume primary consumers

Question 19

Tertiary consumers

Answer 19

consume secondary consumers

Question 20

Detritivores

Answer 20

scavenge waste/dead bodies

Question 21

Decomposers

Answer 21

break down nonliving matter into smaller molecules, cycling nutrients back into the soil

Question 22

Biomass

Answer 22

collective mass of living matter in a place and time

Question 23

Food webs

Answer 23

all interlinking food chains in a community, showing the map of energy flow

Question 24

Keystone species

Answer 24

species with an impact far out of proportion to its abundance (e.g. decomposers recycle nutrients/replenish soil)

Question 25

Top predator

Answer 25

control populations of lower trophic level consumers (often keystone species)

Question 26

Ecosystem engineer

Answer 26

species that physically alters its ecosystem (e.g. beavers and prairie dogs, who are often keystone species)

Question 27

Trophic cascade

Answer 27

top predators are lost and primary consumers overconsume producers, causing an ecological disturbance

Question 28

Disturbance

Answer 28

event with rapid/drastic effects on the community and ecosystem (e.g. tree falls, hurricane, prairie fire, insect outbreaks)

Question 29

Resistance

Answer 29

community that resists change and remains stable

Question 30

Resilience

Answer 30

community that is changed by disturbances but returns to its original state

Question 31

Succession

Answer 31

when severe disturbances eliminate all or most species in a community

Question 32

Pioneer species

Answer 32

one that colonizes during succession, usually with spores/seeds that travel long distances

Question 33

Climax community

Answer 33

species that takes over pioneers

Question 34

Primary succession

Answer 34

disturbance removes all plant soil life

Question 35

Secondary succession

Answer 35

disturbance alters the community, leaving soil life intact (e.g. farming, fires, storms, landslides)

Question 36

Regime shift

Answer 36

entire character of a community changes due to a disturbance

Question 37

Novel communities/no-analog communities

Answer 37

human disturbance mixes species that have not previously occurred on Earth

Question 38

Introduced species

Answer 38

people bring non-native arrivals to a community

Question 39

Invasive species

Answer 39

introduced species that thrive

Question 40

Restoration ecology

Answer 40

study of ways to restore altered areas to their pre-industrialization condition

Question 41

Ecological restoration

Answer 41

restore ecosystem functionality, return community to its pre-settlement condition

Question 42

Biome

Answer 42

regional complex of similar communities, classified primarily by dominant plant life, which is the result of climate

Question 43

Climate diagram/climatograph

Answer 43

depict seasonal changes to temperature/precipitation, helping tell the story of the biome

Question 44

Deciduous forests

Answer 44

mid-latitude forests with relatively even precipitation throughout the year (frozen in winter)

Question 45

Temperate grasslands

Answer 45

prairies/steppes; temperature differences are extreme between winter and summer, rainfall diminishes

Question 46

Temperate rainforests

Answer 46

mid-latitude forests rich in rainfall, mostly containing coniferous trees (contain fertile soil, which is vulnerable to erosion if forests are cleared)

Question 47

Tropical rainforests

Answer 47

diverse tree species at low densities with acidic soils low in organic matter that have lush vegetation, dark, damp interiors, and diverse communities

Question 48

Tropical dry forests

Answer 48

wet and dry seasons that each occupy about half the year, with consistently warm temperature and leaves that are shed during the dry season

Question 49

Savannas

Answer 49

tropical grassland interspersed with acacias, found in dry tropical areas with distinct wet and dry seasons

Question 50

Deserts

Answer 50

driest biome, with less than 25 cm of rain per year - soils have high mineral/low organic matter content; animals must adapt to dry environment

Question 51

Tundras

Answer 51

cold, dry biomes where underground soil is frozen; most directly impacted by climate change and pollution, though humans do not live there

Question 52

Permafrost

Answer 52

underground soil is permanently frozen

Question 53

Boreal forests/taiga

Answer 53

cold with precipitation, dominated by few species of evergreen trees, with acidic, nutrient-poor soil

Question 54

Chaparral

Answer 54

covered by dense thicket of evergreen shrubs, with mild/wet winters and warm/dry summers and frequent fires; climate is introduced by nearby oceans