Download Genetic Variation

GENETIC VARIATION
2.5
GENETIC BIODIVERSIT Y
 Heredity – the passing on of characteristics from parent to
of fspring.
GENETIC BIODIVERSIT Y
 Heredity – the passing on of characteristics from parent to
of fspring.
 Gene – specific length of DNA on a chromosome that has
information that determines a particular protein, which
determines a characteristic/trait
GENETIC BIODIVERSIT Y
 Heredity – the passing on of characteristics from parent to
of fspring.
 Gene – specific length of DNA on a chromosome that has
information that determines a particular protein, which
determines a characteristic/trait
 Alleles – alternative forms of a gene.
GENETIC BIODIVERSIT Y
 Heredity – the passing on of characteristics from parent to
of fspring.
 Gene – specific length of DNA on a chromosome that has
information that determines a particular protein, which
determines a characteristic/trait.
 Alleles – alternative forms of a gene.
 EG – a gene could be for eye colour, and the alleles are for
blue eyes or brown eyes.
GENETIC BIODIVERSIT Y
 Heredity – the passing on of characteristics from parent to
of fspring.
 Gene – specific length of DNA on a chromosome that has
information that determines a particular protein, which
determines a characteristic/trait.
 Alleles – alternative forms of a gene.
 Population – members of a species living together.
GENETIC BIODIVERSIT Y
 Heredity – the passing on of characteristics from parent to
of fspring.
 Gene – specific length of DNA on a chromosome that has
information that determines a particular protein, which
determines a characteristic/trait.
 Alleles – alternative forms of a gene.
 Population – members of a species living together.
 Gene pool - complete set of unique alleles in a species or
population.
GENETIC BIODIVERSIT Y
 Heredity – the passing on of characteristics from parent to
of fspring.
 Gene – specific length of DNA on a chromosome that has
information that determines a particular protein, which
determines a characteristic/trait.
 Alleles – alternative forms of a gene.
 Population – members of a species living together.
 Gene pool - complete set of unique alleles in a species or
population. All the alleles that are present in the population.
GENETIC BIODIVERSIT Y
 Heredity – the passing on of characteristics from parent to
of fspring.
 Gene – specific length of DNA on a chromosome that has
information that determines a particular protein, which
determines a characteristic/trait.
 Alleles – alternative forms of a gene.
 Population – members of a species living together.
 Gene pool - complete set of unique alleles in a species or
population. All the alleles that are present in the population.
 Allele frequency – the number of times that an allele occurs
in a population.
GENETIC BIODIVERSIT Y
 Overall – is about the range of dif ferent alleles present in the
gene pool.
GENETIC BIODIVERSIT Y
 Overall – is about the range of dif ferent alleles present in the
gene pool. The greater the number of dif ferent alleles, the
greater the genetic biodiversity.
GENETIC BIODIVERSIT Y
 Overall – is about the range of dif ferent alleles present in the
gene pool. The greater the number of dif ferent alleles, the
greater the genetic biodiversity.
 Important for survival – greater range of alleles = more
variation = more material for evolution to act upon.
GENETIC BIODIVERSIT Y
 Overall – is about the range of dif ferent alleles present in the
gene pool. The greater the number of dif ferent alleles, the
greater the genetic biodiversity.
 Important for survival – greater range of alleles = more
variation = more material for evolution to act upon.
 With variation, when the environment changes, these
favourable alleles can be selected for by natural selection.
GENETIC BIODIVERSIT Y
 Overall – is about the range of dif ferent alleles present in the
gene pool. The greater the number of dif ferent alleles, the
greater the genetic biodiversity.
 Important for survival – greater range of alleles = more
variation = more material for evolution to act upon.
 With variation, when the environment changes, these
favourable alleles can be selected for by natural selection.
 Natural selection allows the individuals with favourable
alleles to cope with change (and therefore breed and pass on
their ‘good’ genes)

GENETIC BIODIVERSIT Y
 Overall – is about the range of dif ferent alleles present in the
gene pool. The greater the number of dif ferent alleles, the
greater the genetic biodiversity.
 Important for survival – greater range of alleles = more
variation = more material for evolution to act upon.
 With variation, when the environment changes, these
favourable alleles can be selected for by natural selection.
 Natural selection allows the individuals with favourable
alleles to cope with change (and therefore breed and pass on
their ‘good’ genes)
 Favourable alleles often mean adaptations – changes
(structure/behaviour/physiology) that enhance survival.
GENETIC BIODIVERSIT Y
 Overall – is about the range of dif ferent alleles present in the
gene pool. The greater the number of dif ferent alleles, the
greater the genetic biodiversity.
 Important for survival – greater range of alleles = more
variation = more material for evolution to act upon.
 With variation, when the environment changes, these
favourable alleles can be selected for by natural selection.
 Natural selection allows the individuals with favourable
alleles to cope with change (and therefore breed and pass on
their ‘good’ genes)
 Favourable alleles often mean adaptations – changes
(structure/behaviour/physiology) that enhance survival.
 Individuals without fav. Alleles tend to be wiped out =
frequency of ‘bad’ alleles is reduced.
UNFORTUNATELY…
 Biodiversity is not selected for in plant and animals used for
humans – we want them all to be the same (strong, healthy,
good breeders, tall growers, fast growers etc)
UNFORTUNATELY…
 Biodiversity is not selected for in plant and animals used for
humans – we want them all to be the same (strong, healthy,
good breeders, tall growers, fast growers etc)
 This can muck things up because the range of alleles in their
gene pools can be severely limited.
UNFORTUNATELY…
 Biodiversity is not selected for in plant and animals used for
humans – we want them all to be the same (strong, healthy,
good breeders, tall growers, fast growers etc)
 This can muck things up because the range of alleles in their
gene pools can be severely limited.
 This means that if something goes wrong (a disease usually)
the whole population can be wiped out!
UNFORTUNATELY…
 Biodiversity is not selected for in plant and animals used for
humans – we want them all to be the same (strong, healthy,
good breeders, tall growers, fast growers etc)
 This can muck things up because the range of alleles in their
gene pools can be severely limited.
 This means that if something goes wrong (a disease usually)
the whole population can be wiped out!
 Thankfully, there are things being done to reduce this –
captive breeding endangered animals in zoos, seeds stored in
storage banks etc. This will ensure the gene pool has enough
to continue the species.