Concept:This is a monohybrid inheritance cross between two heterozygous parents, each with genotype
Ee.
Explanation:Each
Ee parent produces two types of gametes,
E and
e.
The gametes can combine in four ways inside the Punnett square.
When
E combines with
E, the offspring is
EE, which is homozygous dominant.
When
E combines with
e, the offspring is
Ee, which is heterozygous.
When
e combines with
E, another
Ee offspring is produced.
When
e combines with
e, the offspring is
ee, which is homozygous recessive.
Thus the four labelled offspring, in order, are
EE,
Ee,
Ee, and
ee.
This gives the expected genotypic ratio of
1:2:1.
Answer:I=EE,
II=Ee,
III=Ee, and
IV=ee.
