Pea In Your Genes. Gregor Mendel Liked to play with pea Noticed that certain Characteristics...
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Transcript of Pea In Your Genes. Gregor Mendel Liked to play with pea Noticed that certain Characteristics...
Pea In Your Genes
Gregor Mendel
• Liked to play with pea• Noticed that
certain Characteristics (inheritable physical features) showed up or disappeared in peas.
plants.
Characteristics
• Inheritable physical features – such as yellow peas or wrinkled peas.• Come from Genes – Which come from your
parents.• Also called Traits – could be pea color or
pea shape.
• A single trait can be expressed (shown) in different ways.• Allele is the different
representation of the same trait. Ex. Seed color: Yellow or Green• Yellow is one Allele for
Seed Color• Green is another Allele
Genotype & Phenotype
• Genotype – “code” for a trait• Phenotype – what you actually see. • Yellow peas – Use Y to represent Yellow• Green peas – Use y to represent Green
Yellow and Green Peas
Genotype Phenotype• YY – Yellow• Yy – Yellow• yy - Green
Three different Genotypes but Two Colors. Why?
• YY – Yellow• Yy – Yellow• yy - Green
• Dominant Allele – rep. by a capital letter – Y• Recessive Allele –
rep. by a lowercase letter - yDominant Alleles OVER POWER
Recessive Alleles
• YY – Homozygous Yellow• Yy – Heterozygous
Yellow• yy – Homozygous
Green
How do alleles pass from parent to child?
• Punnett Squares• What if you cross a
Homozygous Yellow Pea (YY) with a Homozygous Green Pea (yy)?
YYYYY
Y
y yyy
yy
100% Heterozygous Yellow Peas
YY
YYYY
y
y yyyy
25% Homozygous Yellow50% Heterozygous Yellow25% Homozygous Green