Transcript Inheritance PowerPoint (Larkeys)

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Purpose: In this investigation, we will find out
how changes can occur in a population due
to variation in traits.
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Traits in a population change over the course of
several generations
Offspring grow up to look pretty much like their
parents.
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This is because the information for how to develop is
passed from the parents to the offspring
Passing genetic information from one
generation to the next generation is called
inheritance.
You inherit alleles from your parents, Larkeys
inherit alleles from their parents. This is true
for all living organisms.
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The pioneering work on inheritance was done
by an Augustinian monk named Gregor Mendel.
He spent years growing thousands of plants
and animals, observing closely to see how
similar they were to their parents.
His most important work was done with pea
plants.
Mendel reasoned that the offspring must be
inheriting something from each parent.
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Everything is made of cells.
This is where the information describing how
to make you resides (is found)
Cells have many smaller structures inside,
called organelles, which perform functions
essential to life.
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http://www.fossweb.com/modulesMS/kit_m
ultimedia/PopulationsandEcosystems/pdfs/
transparencies/Pop_Eco_transp_22.pdf
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DNA and chromosomes are found inside the
nucleus.
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Found inside the nucleus of a cell
Also known as the inheritance messenger
DNA contains millions of atoms
In order to fit inside the nucleus, DNA is
coiled and coiled again into structures called
chromosomes.
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Chromosomes are the structures that carry
the message of inheritance.
They come in almost identical pairs
They have specific active locations called
alleles
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http://www.fossweb.com/modulesMS/kit_m
ultimedia/PopulationsandEcosystems/pdfs/
transparencies/Pop_Eco_transp_23.pdf
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The drawing shows the nucleus of a cell from
our make-believe animal, the Larkey.
There are 8 chromosomes
Chromosomes always come in pairs.
The Larkey has 4 pairs of chromosomes.
Both chromosomes in a pair have dark areas in
exactly the same location. The dark areas are
called alleles.
Two pairs of alleles working together make a
gene
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The alleles are the code that determines the
traits
The combination of alleles in an organism’s
chromosomes is the organism’s genotype.
Two Alleles on paired chromosomes work
together.
Together they are known as a gene
Alleles don’t all have equal influence in
determining traits
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Dominant alleles are more influential in
determining traits
They are represented by an uppercase letter
Recessive alleles are less influential in
determining traits
They are represented by a lowercase letter
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AA or Aa = __________ legs
aa = __________ legs
EE or Ee = __________ eyes
ee = __________ eyes
FF = striped fur pattern
Ff = solid fur pattern
ff = spotted fur pattern
TT or Tt = __________ tail
tt = __________ tail
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http://www.fossweb.com/modulesMS/kit_m
ultimedia/PopulationsandEcosystems/pdfs/
transparencies/Pop_Eco_transp_26.pdf
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A gene is two alleles working together to
control a trait
They determine eye color, hair color, fur
patterns, etc.
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A Larkey has four features that we will focus
on:
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Legs (appendages)
Eye color
Fur pattern
Tail shape
Each feature is controlled by one gene.
Each of the four genes are located on a
different chromosome

http://www.fossweb.com/modulesMS/kit_m
ultimedia/PopulationsandEcosystems/pdfs/
transparencies/Pop_Eco_transp_25.pdf
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http://www.fossweb.com/modulesMS/kit_m
ultimedia/PopulationsandEcosystems/pdfs/
transparencies/Pop_Eco_transp_20.pdf
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http://www.fossweb.com/modulesMS/kit_m
ultimedia/PopulationsandEcosystems/pdfs/
transparencies/Pop_Eco_transp_21.pdf
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http://www.fossweb.com/modulesMS/kit_m
ultimedia/PopulationsandEcosystems/pdfs/
transparencies/Pop_Eco_transp_24.pdf