Question

I need help i need to do a pedigree chart and punnet square in for a simple dimple (S) we get to build our own trait

Answer 1

To answer this question we need to define our trait of interest, later we define our family relationtionships, and in this particular case we can choose who presents the trait of interest, finally, we do a punnet square to prove the proposed pattern of inheritance.

The trait of interest: Smile dimples

Alleles: S= smile dimples (dominant), s= no smile dimples (recessive)

Note: for a recessive trait (in this case no smile dimplis) shows must be homozygous (ss) if the individual is heterozygous (Ss) or dominant homozygous (SS) smile dimple will be present.

Now we define our family relationships

Now having family relationships clear we can choose inheritance patterns

Having inheritance atterns saet we cn do he roproneret squares

stgeneration P,rthe pantal cross is : SS x ss

`\begin{bmatrix}{\placeholder{⬚}} & {s} & {s} \\ {S} & {Ss} & {Ss} \\ {S} & {Ss} & {Ss}\end{bmatrix}`

Frequencies: All are heterozygous and have smile dimples

2nd generation

Jimmy x Ara: Ss x Ss

Fred x Brittney. Ss x SS

Brooklyn x Timmy: Ss x ss

`\begin{bmatrix}{\placeholder{⬚}} & {S} & {s} \\ {S} & {SS} & {Ss} \\ {s} & {Ss} & {ss}\end{bmatrix}\text{ }\begin{bmatrix}{\placeholder{⬚}} & {S} & {s} \\ {S} & {SS} & {Ss} \\ {S} & {SS} & {Ss}\end{bmatrix}\text{ }\begin{bmatrix}{\placeholder{⬚}} & {s} & {s} \\ {S} & {Ss} & {Ss} \\ {s} & {ss} & {ss}\end{bmatrix}`

Frequencies

Jimmy x Ara (SsxSs)

Genotypic: 1:2:1 (one dominant homozygous, two heterozygous, one recessive homozygous)

Phenotypic:3:1 (three dimples, one no dimples)

Fred x Brittney (SsxSS)

Genotypic: 2: 2 (two dominant homozygous, two heterozygous)

Phenotypic: 4 (All have dimples)

Brooklyn x Timmy (Ssxss)

Genotypic: 2:2 (Two recessive homozygous,thw heterozygous)

Phenotypic: 2:2 (Two with dimples, two no dimples)