Chapter 15: Ecology

Question 1

ecology

Answer 1

-study of interactions of organisms with their physical environment and with each other

Question 2

population

Answer 2

-group of a species that are can interbreed and interact with each other

Question 3

community

Answer 3

-all organisms in one area

Question 4

ecosystem

Answer 4

-organisms and abiotic factors that they interact with

Question 5

biosphere

Answer 5

-global ecosystem

Question 6

size

Answer 6

-number of individuals in a population

Question 7

density

Answer 7

-number of individuals per unit area

Question 8

dispersion

Answer 8

-pattern of spacing of individuals within the are

Question 9

biotic potential

Answer 9

-maximum rate at which a population could increase under ideal conditions

Question 10

limiting factors

Answer 10

• factors that limit population growth
• density-dependent: factors that increase as population density increases (predation)
• density-independent: factors whose occurrence is unrelated to the population density (earthquakes)

Question 11

species richness

Answer 11

-number of different species in a community

Question 12

relative abundance

Answer 12

-contributes to species diversity

Question 13

competitive exclusion principle

Answer 13

-two species can’t coexist in a community if they share the same niche (same role)

Question 14

resource partitioning

Answer 14

-one species that is competing for a resource will evolve through natural selection to exploit different resources

Question 15

character displacement

Answer 15

-divergence in body structure

Question 16

aposematic coloration

Answer 16

-bright coloration that warns predators of possible poison

Question 17

batesian mimicry

Answer 17

• copycat coloration in which one harmless animal mimics the coloration of one that is poisonous
• viceroy and monarch butterfly

Question 18

mullerian mimicry

Answer 18

-two or more poisonous species resemble each other and gain advantage from their combined numbers

Question 19

mutalism

Answer 19

-symbiotic relationship in which both organisms benefit

Question 20

commensalism

Answer 20

-symbiotic relationship in which one organism benefits and the other is unaffected

Question 21

gross primary productivity (GPP)

Answer 21

-amount of light energy converted to chemical energy by photosynthesis per unit time

Question 22

net primary productivity (NPP)

Answer 22

-GPP minus energy used by primary producers during cellular respiration

Question 23

food pyramid

Answer 23

-represent the interactions of organisms in a food chain from one trophic level to the next

Question 24

food web

Answer 24

-interwoven food chains

Question 25

dominant species

Answer 25

-most abundant (have the largest biomass)

Question 26

keystone species

Answer 26

-exert major control over other species in a community

Question 27

ecological succession

Answer 27

-sequential rebuilding of an ecosystem after a disaster

Question 28

primary ecoloical succession

Answer 28

-soil building through introduction of pioneer organisms

Question 29

secondary ecological succession

Answer 29

-occurs when the soil is still intact after a disaster

Question 30

nitrogen-fixing bacteria

Answer 30

-convert free nitrogen to ammonium ion

Question 31

acid rain

Answer 31

-caused by combustion of fossil fuels

Question 32

greenhouse effet

Answer 32

• CO2 and water vapor in the atmosphere absorb and retain heat of Earth
• increased levels of atmospheric CO2 i because of global warming