Populations

Question 1

What is a population?

Answer 1

A group of organisms from the same species in the same area, chose to breed and share a gene pool

Question 2

What is the best way to determine population size?

Answer 2

Collect an absolute number

Question 3

What is indirect sampling?

Answer 3

Looks at evidence left behind

Question 4

What are the patterns of disposal?

Answer 4

Clumped, spaced and random

Question 5

What are reasons for clumped dispersal?

Answer 5

Safety, social grouping or uneven resources

Question 6

What are reasons for spaced dispersal?

Answer 6

Territory and high intraspecific competition

Question 7

What is random dispersal?

Answer 7

Least common where dont interact much

Question 8

What do survivorship curves show?

Answer 8

Pattern of lifespan in a population

Question 9

What does a positive survivorship curve show?

Answer 9

Most individuals reach adulthood and there is a large die-off of individuals as the population nears the end of a normal lifespan

Question 10

What does a straight survivorship curve show?

Answer 10

A fairly constant mortality rate though the lifespan of the population

Question 11

What does a negative survivorship curve show?

Answer 11

High mortality rate of the young, but those individuals that do reach maturity live a long life with a low death rate

Question 12

What do population dynamics investigate?

Answer 12

Population size

Question 13

What is the growth rate?

Answer 13

Number of organisms born over time

Question 14

What affects growth rate?

Answer 14

Birth rate and death rate

Question 15

What is biotic potential?

Answer 15

If all organisms reproduce as much as possible and none of the offspring die

Question 16

What are issues with small populations?

Answer 16

Low genetic diversity, subject to inbreeding, less likely to adapt to environmental changes and low mates

Question 17

What are issues with large populations?

Answer 17

Increased food shortages and diseases, decrease in space and clean water and live at carrying capacity so can experience huge crash

Question 18

What are the stages on a population curve?

Answer 18

Log, exponential and stationary

Question 19

What does the lag phase look like?

Answer 19

An exponential curve

Question 20

What is happening at the lag phase?

Answer 20

The rate is accelerating and there is slow growth due to few reproducing individuals

Question 21

What does the exponential phase look like?

Answer 21

A straight line

Question 22

What is happening at the exponential phase?

Answer 22

The rate is the fastest, there is rapid growth and nothing is limiting

Question 23

What does the stationary phase look like?

Answer 23

A wavy line with small fluctuations

Question 24

What is happening in the stationary phase?

Answer 24

Small fluctuations are due to resources, environmental resistance as something is limiting and birth = death

Question 25

What is environmental resistance?

Answer 25

Something is a limiting factor

Question 26

What are limiting factors?

Answer 26

Any factor that causes a population to decease

Question 27

What are types of limiting factors?

Answer 27

Density dependant and density independent

Question 28

What are density dependant factors?

Answer 28

Depends on size of population

Question 29

What are density independant factors?

Answer 29

Effects populations regardless of density

Question 30

What are density dependant factors?

Answer 30

Shelter, disease, competition, food, waste build up and water

Question 31

What are density independant factors

Answer 31

Fire, tornadoes, volcanoes, climate, floods and weather