↳ and
the
study of the interactions of organisms with their
physical biological environment
and how these determine the distribution and make up of populations within an
ecosystem
↳
concerned with fluctuations in size of a population and the factors (physical and social )
that these fluctuations
regulate
Definitions
individual
single organism capable of independent existence
•
-
species group of organisms with similar characteristics that are capable of breeding with
•
-
one another and
producing fertile offspring
groups of different species of organisms that interact with each other and the
ecosystem
•
-
environment
group of different species that inhabit and interact in a particular area
-
community
•
population individuals of the same species that
group of the same area and can
° -
occupy
breed with one another
freely
Populationparameters
↳
factors that affect the size of the population (total number of individual in a population)
birth / natality increases population size
•
-
death / decreases population
mortality size
°
-
•
immigration
-
increases population size as individuals move into an area
decreases population individuals of
emigration size as move out an area
-
•
↳
population remain stable when birth and immigration approximately equal death and
emigration
↳ in a closed population ,
with no
immigration /emigration ,
the only parameters affecting any
change in population numbers will be births 1deaths leg .
fish in a small pond )
,Howisgrowthofapopulationregulated.tl
Environmental resistance : factors that stop a
←
population from reproducing at a maximum rate
←
carrying capacity : the population
density that the
environment can support
←
Exponential growth : increasing more
rapidly
Stablepopulation
↳
if individuals enter unoccupied area where there is no of food / resources and
an shortage no
predators they will reproduce and the number of individuals will increase
,
exponentially
↳
as the numbers increase more demands are made
,
on the available resources and this builds
up environmental resistance which cause the birth /immigration rate to decrease and the death /
emigration rate to increase
↳
eventually a balance is reached and the population stabilizes at particular number / size (carrying
capacity )
↳
population fluctuates around carrying capacity until the environment changes
↳
and available resources
population size fluctuates seasonally annually depending on the
feedback )
↳
population size is
self-regulating leg negative
.
Unstablepopulation
Carrying capacity of an environment can
change :
if a population exceeds carrying capacity seen in the
•
.
graph on the left
•
if a drought occurs ,
this can reduce
carrying capacity
This results in the habitat :
deteriorating rapidly which reduces
•
,
carrying capacity
eventually not being able to support the population
'
,
which will decrease
rapidly and become exinct
.
the
study of the interactions of organisms with their
physical biological environment
and how these determine the distribution and make up of populations within an
ecosystem
↳
concerned with fluctuations in size of a population and the factors (physical and social )
that these fluctuations
regulate
Definitions
individual
single organism capable of independent existence
•
-
species group of organisms with similar characteristics that are capable of breeding with
•
-
one another and
producing fertile offspring
groups of different species of organisms that interact with each other and the
ecosystem
•
-
environment
group of different species that inhabit and interact in a particular area
-
community
•
population individuals of the same species that
group of the same area and can
° -
occupy
breed with one another
freely
Populationparameters
↳
factors that affect the size of the population (total number of individual in a population)
birth / natality increases population size
•
-
death / decreases population
mortality size
°
-
•
immigration
-
increases population size as individuals move into an area
decreases population individuals of
emigration size as move out an area
-
•
↳
population remain stable when birth and immigration approximately equal death and
emigration
↳ in a closed population ,
with no
immigration /emigration ,
the only parameters affecting any
change in population numbers will be births 1deaths leg .
fish in a small pond )
,Howisgrowthofapopulationregulated.tl
Environmental resistance : factors that stop a
←
population from reproducing at a maximum rate
←
carrying capacity : the population
density that the
environment can support
←
Exponential growth : increasing more
rapidly
Stablepopulation
↳
if individuals enter unoccupied area where there is no of food / resources and
an shortage no
predators they will reproduce and the number of individuals will increase
,
exponentially
↳
as the numbers increase more demands are made
,
on the available resources and this builds
up environmental resistance which cause the birth /immigration rate to decrease and the death /
emigration rate to increase
↳
eventually a balance is reached and the population stabilizes at particular number / size (carrying
capacity )
↳
population fluctuates around carrying capacity until the environment changes
↳
and available resources
population size fluctuates seasonally annually depending on the
feedback )
↳
population size is
self-regulating leg negative
.
Unstablepopulation
Carrying capacity of an environment can
change :
if a population exceeds carrying capacity seen in the
•
.
graph on the left
•
if a drought occurs ,
this can reduce
carrying capacity
This results in the habitat :
deteriorating rapidly which reduces
•
,
carrying capacity
eventually not being able to support the population
'
,
which will decrease
rapidly and become exinct
.
