Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

Stutt with the phenotype which will give you an idea of what your genotype is. I

ID: 92920 • Letter: S

Question

Stutt with the phenotype which will give you an idea of what your genotype is. In complete dominance a dominant trait caneither be homozygous dominant (AA) or heterozygous (Aa). There is no way for us to tell which one it is. If you encounter this situation, flip the coins to determine your genotype. Two heads means homozygous dominant while a head and tails means heterozygous. Conveisely, if you are recessive for a trait, then you must be homozygous recessive (aa). If you are workrng with an incomplete dominance trait, then you will either be homozygous dominant, heterozygous, or homozygous recessive, This is a clear cut situation. I'm confused in finding the genotype?

Explanation / Answer

In incomplete dominance, a cross between organisms with two different traits will produce offsprings with a third trait that is a mixture of both parental traits.

For example, in a cross between black coloured mice and white coloured mice, grey mice are formed. Grey colour is the result of the presence of both white and black colour alleles.

Offsprings are all grey coloured.

F2 generation: breeding between two grey coloured mice is shown below.

BB is black coloured

BW is grey coloured and

WW is white coloured

The ratio in F2 generation is 1:2:1

In incomplete dominance, we either have homozygous dominant (both the parents in above example) or heterozygous dominant (F1 offsprings). There is no homozygous recessive in incomplete dominance. I hope this clears your confusion.

B B W BW BW W BW BW