Chapter 20

Question 1

Population

Answer 1

a group of individuals of the same species, in the same area, at the same time

Question 2

studying individuals in population can provide info on:

Answer 2

life span, food preferences, reproductive cycle

Question 3

Community

Answer 3

• Made up the populations of all organisms that occupy an area
• study how different populations interact with one another (competition, predation, parasitism, mutualism, etc.)

Question 4

Ecosystem

Answer 4

Includes community (biotic factors) and surrounding abiotic factors

Question 5

intraspecific competition

Answer 5

how individual members of one species interact with each other

Question 6

interspecific competition

Answer 6

can describe how population interacts with each other

Question 7

Geographic Range

Answer 7

region where a given organism is sighted

Question 8

Habitat

Answer 8

• the physical area where a species lives
• usually determine by the environmental conditions under which the population has the best chance of survival
• habitat is limited by factors such as climate, soil conditions, vegetation, etc.

Question 9

Ecological Niche

Answer 9

the overall role of a species in its environment

Question 10

A statement of the size of a population must include:

Answer 10

the number of organisms, the location, the time when numbers were determines

Question 11

Natality

Answer 11

number of offspring of a species born in one year

Question 12

Mortality

Answer 12

number of offspring of species that die in one year

Question 13

immigration

Answer 13

number of individuals of species moving into existing population

Question 14

emmigration

Answer 14

number of individuals of species leaving existing population

Question 15

Dynamic Equillibrium

Answer 15

in mature ecosystems, populations tend to remain stable and adjust to changes in their environment - balance is known as dynamic equillibrium

Question 16

Open population

Answer 16

one is which density changes as a result from the interaction of natality, mortality, immigration and emmigration

Question 17

Closed Population

Answer 17

one in which density changes as a result from just natality and mortality with neither food or wastes being allowed to enter of leave the given environment

Question 18

population explosion

Answer 18

population that grows so rapidly before it can be contained

Question 19

population crash

Answer 19

population that declines so rapidly

Question 20

Biotic Potential

Answer 20

the highest possible per capita growth rate for a population (given unlimited resources and ideal living conditions)

Question 21

Factors that determine a species’ biotic potentia; include

Answer 21

1. number of offspring per reproductive cycle
2. the number of offspring that survive long enough to reproduce
3. the age of reproductive maturity and the number of times the individuals reproduce in life span
4. the life span of the individuals

Question 22

organisms that have high biotic potention

Answer 22

small animals, microorganisms, certain plants

Question 23

organisms that grow their biotic potential demonstrate:

Answer 23

exponential growth (J shape)

Question 24

Lag Phase

Answer 24

In the beginning, growth of small population is slow (since only a few reproduce)

Question 25

Growth Phase

Answer 25

as numbers in population increase, population will experience exponential rate of growth,
(birth > death)

Question 26

Stationary Phase

Answer 26

birth rate = death rate

Question 27

S shaped curve

Answer 27

logistic growth pattern

Question 28

Carrying Capacity (K)

Answer 28

the theoretical maximum population size that the environment can sustain over an extended period of time. same as the number of individuals in population that can live in a given environment without depleting resources they need or harming their habitat or themselves

Question 29

factors that limit a habitat’s carrying capacity

Answer 29

1. Density dependent factors (biotic)
2. Density independent factors (abiotic)

Question 30

Environmental resistance

Answer 30

-combination of all limiting factors
-prevents population from growing at its biotic potential
-determines carrying capacity of a habitat

Question 31

In unstable environments…

Answer 31

it may be favourable to reproduce quickly when conditions are favourable

Question 32

In stable environments..

Answer 32

it may be favourable to reproduce slowly

Question 33

r- selected life strategies

Answer 33

organisms that reproduce close to their biotic potential

Question 34

K- selected life strategies

Answer 34

populations that live close to their carrying capacity of their habitats

Question 35

r selected life strategy characterisitcs

Answer 35

• small size
• short life span
• early reproductive age
• produce large broods of offspring that receive little to no parental care
• take advantage of favourable conditions such as availability of food, sunlight, and warm temps

Question 36

K selected life strategies characteristics

Answer 36

• typically large size
• long life span
• later reproductive age
• produce few offspring per reproductive cycle. offspring require parental care