Ch 41: Ecology

Question 1

Community

Answer 1

is an assemblage of species living close enough for potential interaction.

Question 2

General things about interspecific

Answer 2

• Interspecific interactions can be positive of one species (+), negative (-), or neutral (0)
• Interspecific interactions include competition(only occurs when scarce resources), predation, and symbioses
• Interspecific (different species) Intraspecific ( same species)
• Interspecific competition can result in the elimination of one of the species. (a reproductive advantage in one species)

Question 3

Interspecific competition

Answer 3

occurs when resources are in short supply, It is a -/- interaction between species involved

Question 4

Competitive exclusion principle

Answer 4

When two species are vying for a resource, eventually the one with the slight reproductive advantage will eliminate the other. (resource partitioning)

Question 5

An Ecological Niche

Answer 5

sum total of biotic and abiotic resources in its environment.

Question 6

2 types of ecological niches

Answer 6

Fundamental niche and Realized niche

Question 7

Fundamental niche

Answer 7

what a species potentially occupies

Question 8

Realized niche

Answer 8

the portion of the fundamental niche the species actually occupies (because of comp)

Question 9

How does competition occur?

Answer 9

When niches overlap competition occur

Question 10

Predator prey interaction - or + or 0

Answer 10

prey interactions are +/- between two species

Question 11

Cryptic coloration

Answer 11

camouflaged by coloring

Question 12

Aposematic coloration

Answer 12

the poisonous animal is brightly colored as a warning

Question 13

Batesian mimicry

Answer 13

nonpoisonous look like poisonous

Question 14

Mullerian mimicry

Answer 14

Bad tastingresemble each other, predators avoid equally

Question 15

Herbivory, - + 0

Answer 15

is also a +/- interaction, Herbivores eat only part of a plant or alga

Question 16

Plant protective devices are

Answer 16

chemical toxins, spines, and thorns

Question 17

Symbiosis

Answer 17

occurs when two or more species live in direct contact with one another

Question 18

Parasitism

Answer 18

+/- interaction, the parasite derives its nourishment from the host. This decreases the survival, reproduction, and density of the host population

Question 19

Mutualism

Answer 19

+/+ interaction, both species benefit,

Question 20

Commensalism

Answer 20

+/0 interaction, one benefits the other is neither harmed nor benefits,

Question 21

Species diversity

Answer 21

a measure of the number of different species in a community (species richness) and the relative abundance of each species

Question 22

Trophic Structure

Answer 22

feeding relationships among organisms

Question 23

Trophic levels

Answer 23

links in the trophic structure of a community

Question 24

Flow of Energy is ?

Answer 24

Energy is transferred from the sun to plants to herbivores to carnivores and finally to decomposers.

Question 25

Dominant Species

Answer 25

in a community the species with the highest biomass (all members of pop) or most abundant

Question 26

Keystone Species

Answer 26

exert control on the community because of its important niche (a role it plays)

Question 27

Ecosystem engineers

Answer 27

cause physical changes in the environment that affect community structure

Question 28

The bottom-up model of community organization

Answer 28

proposes a unidirectional influence from lower to higher trophic levels

Question 29

top-down model

Answer 29

proposes that control comes from the trophic level above

Question 30

Biomanipulation

Answer 30

can help restore polluted communities

Question 31

Disturbance and Diversity

Answer 31

Storm, fire, flood, drought, or human activity can be a disturbance and change a community by removing organisms or changing resource availability.

Question 32

Intermediate disturbance hypothesis

Answer 32

moderate levels of disturbance create conditions that foster greater species diversity than low or high levels of disturbance

Question 33

Ecological Succession

Answer 33

the transition in species composition

Question 34

Primary Succession

Answer 34

Plants and Animals gradually invade region that was Lifeless  (pioneer species)

Question 35

Secondary Succession

Answer 35

The existing community has been cleared by a disturbance that leaves the soil intact (ex. Fire)

Question 36

Stages of succession

Answer 36

- **Early-arriving species and later-arriving species may be linked in one of three processes** - **Early arrivals may facilitate the appearance of later species by making the environment favorable** - **They may inhibit the establishment of later species** - **They may tolerate later species but have no impact on their establishment**

Question 37

Two most important biogeographic factors

Answer 37

Latitude of the community and Area of the community

Question 38

Latitude of the community

Answer 38

plants and animals are generally more abundant and diverse in the tropics and become less diverse as you  move toward the poles

Question 39

Area of the community

Answer 39

the larger the  geographic area of a community the more species it has (if all other factors are held equal

Question 40

Island biogeography

Answer 40

the study of “islands” is primarily by two factors

Question 41

Rates of immigration and extinctions are influenced primarily by the ___and ___ of the island from the mainland (source)

Answer 41

size and distance

Question 42

Greater sizes of the island

Answer 42

higher the immigration rates and lower the extinction rates.

Question 43

As the distance from the mainland increase,

Answer 43

the rate of immigration falls, extinction rate increases.