20.1-

Question 1

formula for population density

Answer 1

D= NA (n= #organisms a= area)

Question 2

3 patterns for distribution

Answer 2

1) Uniform
2)Random
3)Clumped

Question 3

Uniform=

Answer 3

even distribution
eg- agriculture

Question 4

Random distribution occurs where…

Answer 4

resources are abundant and there’s little competition

Question 5

Clumped=

Answer 5

organisms grouped together in certain areas

Question 6

4 factors affecting population growth

Answer 6

Birth, death, immigration, emigration

Question 7

birth rate is AKA

Answer 7

Natality

Question 8

Death rate is aka

Answer 8

mortality

Question 9

formula for calculating population growth

Answer 9

^N= (b+i) - (d+e)

Question 10

growth rate formula is

Answer 10

gr= ^N/^t

Question 11

Growth rate=

Answer 11

change in population over time

Question 12

population explosion=

Answer 12

rapid increase in population that happens too fast to be contained

Question 13

population crash=

Answer 13

rapid decrease in population

Question 14

per Capita GR (cgr) takes into account…

Answer 14

initial population size

Question 15

per Capita cgr=

Answer 15

^N/N= Nf-Ni/N

Question 16

Biotic potential (r)=

Answer 16

The highest possible per Capita GR

Question 17

Biotic potential is AKA ___

Answer 17

exponential growth

Question 18

Different species have ____ exponential growth

Answer 18

different

Question 19

Factors affecteing biotic potential (5)

Answer 19

1) # of offspring per reproductive cycle
2)# of offspring to reach reproductive age
3) Age of reproductive maturity
4) # of times and individual reproduces
5) Life span of individuals

Question 20

lag phase=

Answer 20

low population growth due to few organisms able to reproduce

Question 21

exponential growth phase=

Answer 21

rapid increase in population due to an increase in birth rates compared to death rates

Question 22

why cant exponential growth continue forever

Answer 22

competition and limiting factors slow growth

Question 23

stationary phase=

Answer 23

birth and death rates are equal

Question 24

Logistical GR results in ____

Answer 24

an S shaped graph

Question 25

Carrying capacity (k)=

Answer 25

theoretical maximum for a stable population

Question 26

Density dependent factors=

Answer 26

biotic factors that limit carrying capacity
eg- predators, parasites, disease

Question 27

Density independent factors=

Answer 27

abiotic factors that limit carrying capacity as well as growth regardless of population size
eg. floods, drought, fires

Question 28

environmental resistance=

Answer 28

total effect of all limiting factors preventing a population from growing at its biotic potential

Question 29

characteristics of r- selected (5)

Answer 29

short life span
small in size
early reproduction age
many offsrpring
affected by density- dependant factors

Question 30

characteristics of k- selected

Answer 30

Larger animals, slow reproduction rates, longer life span, fewer offspring, affected by density- dependant factor

Question 31

open populations _____ but closed populations have _____

Answer 31

allow immigration
no immigration