Download Inheritance Patterns Name Definition Visual Example Punnett

Inheritance Patterns
Name
Normal
Dominance
Incomplete
Dominance
Definition
One allele can mask
another recessive in
heterozygous individuals.
Form of intermediate
inheritance in which
one allele for a specific
trait is not completely
dominant over the other
allele. This results in a
third phenotype that is a
combination of the
dominant and recessive
phenotypes.
Codominance Form of inheritance where
the traits expressed by
the alleles are equal in
the phenotype.
Sex-Linked
Trait controlled by a gene
located on the sex
chromosome, usually the
X, making it more likely for
males to express the
recessive trait.
Visual Example
Homozygous red flower
(RR) X white flower (rr) will
result in 100% red
offspring.
Homozygous red flower
(RR) X homozygous white
flower (WW) will result in
100% pink flowers.
Homozygous red flower
(RR) X homozygous white
flower (WW) will result in
100% red and white polka
dot flowers.
A cross between a
heterozygous red female
and red male can produce
male white flowers.
Punnett Square
R
R
r
Rr
Rr
r
Rr
Rr
R
R
W
RW
RW
W
RW
RW
R
R
W
RW
RW
W
RW
RW
XR
Xr
XR
XR XR
XR Xr
Y
XR Y
Xr Y
Real Example
Normally pigmented skin
(presence of melanin pigment) is
dominant over albinism (lack of
melanin pigment).
A person with curly hair and
person with straight hair will have
offspring with wavy hair.
Blood Type. There are three alleles
for blood type. 2 alleles produce
surface antigens A or B. The third
allele O produces no antigens.
Both alleles inherited from your
parents are expressed. That is
why some people can have type
AB blood.
Hemophilia (a blood clotting
disorder) and color blindness are
recessive mutations located on
the X chromosome. Because
males have only on X, they are
more likely to have these
disorders. Most females would
have the dominant allele to mask
the recessive one.