Population Ecology

Question 1

Ecology

Answer 1

The study of interactions of organisms with other organisms and the physical environment

Question 2

Habitat

Answer 2

Place where an organism lives

Question 3

Species

Answer 3

Group of organisms that share similar characteristics that are able to interbreed to produce viable and fertile offspring

Question 4

Population

Answer 4

Group of organisms of the same species present in the same area at the same time where interbreeding can take place

Question 5

Community

Answer 5

All different populations found in the same habitat

Question 6

Population density

Answer 6

Number of individuals per unit area/volume

Question 7

Population distribution

Answer 7

Pattern of dispersal of individuals within the area of interest

Question 8

Population size

Answer 8

Number of individuals in a population

Question 9

What are the 4 factors that affect population size?

Answer 9

• natility (births)
• immigration (enter)
• mortality (deaths)
• emigration (exit)

Question 10

What makes a population size stable

Answer 10

Births + immigration = deaths + emigration

Question 11

Two types of ways to calculate population size

Answer 11

Direct and indirect

Question 12

Census

Answer 12

Example of direct method in determining human population size

Question 13

What are two types of indirect methods to count populations

Answer 13

Mark-and-recapture

Quadrate method

Question 14

What are the 6 factors that regulate population size

Answer 14

Carrying capacity 
Dencity-dependent factors 
Density-independent factors 
Competition 
Territoriality 
Predation

Question 15

Carrying capacity

Answer 15

Maximum number of individuals of a given species the environment can support

Question 16

What are the 6 density dependent factors

Answer 16

Disease 
Competition 
Predators 
Parasites 
Food 
Crowding

Question 17

What are the 7 types of density independent factors?

Answer 17

Volcanic eruptions 
Extreme temps
Storms
Floods
Droughts
Chemical pesticides 
Major habitat disruption

Question 18

When does competition arise between individuals

Answer 18

When resources are limited

Question 19

What is territoriality

Answer 19

An area chosen by male member in a population to secure and protect resources, breeding spaces etc

Question 20

How does territoriality play a part in regulation population size

Answer 20

Because individual who don’t manage to establish territory fail to breed successfully and move out of area

Question 21

When does a logistic growth curve occur

Answer 21

When environmental resistance comes into play and retards exponential growth

Living population must eventually come under control by environmental resistance

Question 22

The exponential/geometric growth phase is characterized by what two phases?

Answer 22

Lag phase

Exponential growth phase

Question 23

If a population starts growing in a exponential fashion and resources what happens

Answer 23

It “crashes”

Question 24

What is the “R species”

Answer 24

Multiply fast in an environment that does not last long

Question 25

What is the “k species”

Answer 25

Survive on habitats where there is intense competition for limited resources

Question 26

What does a community consist of

Answer 26

Producers Consumers Decomposers

Question 27

What is a producer

Answer 27

Organisms that create their own food during photosynthesis

Question 28

What are consumers

Answer 28

Organisms that obtain food from other organisms

Question 29

What are decomposers

Answer 29

Organisms that obtain nutrients from dead organic materials

Question 30

What are the 4 types of interactions in a community

Answer 30

Predation Competition Parasitism Mutualism

Question 31

What is specialization

Answer 31

Way in which individual species coexist in a community

Question 32

What is a predator

Answer 32

An organism that hunts prey

Question 33

What is predation

Answer 33

The symbiotic relationship between predator and prey

Question 34

Why does a predator and the environment benefit from predation

Answer 34

Predators obtain food Environment benefits because predations keeps number of herbivores in check to keep carrying capacity stable

Question 35

What does predator-prey interactions show

Answer 35

When prey increases, predators increases When prey decreases, predators decrease

Question 36

What is an opportunistic predator

Answer 36

Do not specialize in hunting one specific type of prey

Question 37

What is competition

Answer 37

The relationship in which organisms compete for the same resources

Question 38

What is interspecific competition

Answer 38

Competition between individuals of different species

Question 39

What is intraspecific competition

Answer 39

Competition between individuals of the same species

Question 40

What is competitive exclusion

Answer 40

Refers to the principle that when 2 species compete for the same resources within an environment, one of them will eventually outcompete and displace the other

Question 41

What is resource partitioning

Answer 41

With limited resources one of the species will start utilizing different resources Where resources in environment are limited, different species have evolved to share specific resources

Question 42

What is parasitism

Answer 42

Symbiotic relationship I’m whine one organism benefits, while the other is harmed

Question 43

What is a parasite

Answer 43

Organisms that live in or on host species and derives all their requirements and damage host in process

Question 44

What is mutualism

Answer 44

Symbiotic relationship in which both organisms benefit from association

Question 45

What is commensalism

Answer 45

Symbiotic relationship in which one organism benefits while the other is not harmed but does not benefit

Question 46

What is social organizations

Answer 46

Structured organization of individuals within a population

Question 47

What is succession

Answer 47

Process of community change over time

Question 48

What are the two types of ecological succession

Answer 48

Primary and secondary succession

Question 49

What is primary succession

Answer 49

The initial development of plant or animal communities in an area where no soil initially exists

Question 50

What are the stages of primary succession

Answer 50

Pioneer organisms seethe on barren rock Spores of moss plants settle+grow there Fern spores blown in and replace moss Seed settle + germinate in shade of ferns Shrubs replace ferns Trees replace shrubs Eventually for true forest = climax community

Question 51

What is a climax species

Answer 51

Species of organisms present when community has reached final stage of succession

Question 52

What is secondary succession

Answer 52

Development of new inhabitants to replace previous community of plants and animal disturbed by an event like fire

Question 53

What is pioneer succession

Answer 53

A plant species that dominates community in the first stage of succession

Question 54

What is an ecological footprint

Answer 54

A measure of human demand in Eats’s ecosystems

Question 55

What is fecundity

Answer 55

Number of offspring a female can produce during her lifetime