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Example Questions
Example Question #91 : Inheritance
A white homozygous recessive plant is crossed with a homozygous dominant red plant. The plants produced from this cross are all pink. What kind of inheritance does this plant's color follow?
Multiple alleles
Complete dominance
Codominance
Incomplete dominance
Sex-linked dominance
Incomplete dominance
In incomplete dominance, heterozygotes express an intermediate phenotype. Since neither parent expresses the pink phenotype, we know that plant color follows incomplete dominance since neither red nor white is fully expressed as would be the case with complete dominance; rather they are both incompletely expressed.
Example Question #92 : Inheritance
Which occurs when a heterozygous genotype produces blended traits?
Trisomy
Pure genotype
Monosomy
Incomplete dominance
Codominance
Incomplete dominance
Incomplete dominance involves expression of an intermediate phenotype. The heterozygotes express a phenotype that is a blend of both the dominant and recessive phenotypes. One common example is a flower with white petals and a flower with red petals sexually reproduce to create flowers with pink petals.
Example Question #93 : Inheritance
Which of these is an example of polygenic inheritance?
Skin color
Color blindness
Duchenne muscular dystrophy
Freckles
Sickle cell anemia
Skin color
Polygenetic inheritance is where multiple genes affect a single trait. Human skin color depends on three sets of alleles: Aa, Bb, and Cc. A cross between two parents with any combination of these three alleles determines skin color; there is no single skin color gene.
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