Polygenic Inheritance: The height of a particular strain of corn is a result of
ID: 259578 • Letter: P
Question
Polygenic Inheritance: The height of a particular strain of corn is a result of polygenic inheritance involving three genes. The dominant allele for each gene can contribute 5 cm. to the plant’s height. The base height of the corn stalk is 10 cm. and the tallest plant can reach 40 cm.
A. What is the genotype of the tallest plant? (Use A, B, and C for the genes)
B. What is the genotype of the shortest plant?
C. An AABBCC plant is crossed to an aabbcc plant. What is the height of the resulting F1 plants?
D. How tall will an AaBBCc plant be? E. How tall will an AABBCc plant be?
Explanation / Answer
A) Tallest plant will have genotype AABBCC ( 5+5 + 5 +5 + 5 + 5 +10 = 40 cm) as it is a polygenic trait heterozygous will be AaBbCc will not be tallest it will be intermediate.
B) shortest will be aabbcc
C) the cross will result in AaBbCc ( 5 + 2.5 + 5 + 2.5 + 5 + 2.5 = 22.5 cm) + 10 cm base = 32.5 cm
D) Height will be ( 5 + 2.5 + 5 +5 +5 + 2.5 = 25 cm) + 10 cm = 35 cm
E) 5 + 5+5+5+5+2.5+10 = 37.5 cm