LECTURE 7:
Mendelian Polyhybrid Inheritance
(Independent assortment)
, Gregor Johann Mendel
(1822-1884)
"father of modern genetics"
, POLYHYBRID INHERITANCE
(a) Crosses With Two Traits (Dihybrid Cross)
• Two traits per cross, a cross that concerns two traits is
known as a dihybrid cross
• Dihybrid cross - a cross between two parents that
differ by two pairs of alleles (AABB x aabb)
• Dihybrid- an individual heterozygous for two pairs of
alleles (AaBb)
• Started with true-breeding plants that had smooth,
yellow seeds and crossed them with true-breeding
plants having green, wrinkled seeds.
• Round (smooth) seeds (R) are dominant over wrinkled
(r) seeds. Yellow seed color (Y) is dominant over
green (y)
Mendelian Polyhybrid Inheritance
(Independent assortment)
, Gregor Johann Mendel
(1822-1884)
"father of modern genetics"
, POLYHYBRID INHERITANCE
(a) Crosses With Two Traits (Dihybrid Cross)
• Two traits per cross, a cross that concerns two traits is
known as a dihybrid cross
• Dihybrid cross - a cross between two parents that
differ by two pairs of alleles (AABB x aabb)
• Dihybrid- an individual heterozygous for two pairs of
alleles (AaBb)
• Started with true-breeding plants that had smooth,
yellow seeds and crossed them with true-breeding
plants having green, wrinkled seeds.
• Round (smooth) seeds (R) are dominant over wrinkled
(r) seeds. Yellow seed color (Y) is dominant over
green (y)
