A metallic blue-colored Indian blue peahen with long pinion feathers is crossed with a dull brown-colored Indian blue peacock with short pinion feathers. Half of the resulting peacocks are metallic blue with short pinions and half the resulting peacocks are metallic blue with long pinions. Half of the resulting peahens are dull brown with short pinions and half the peahens are dull brown with long pinions. Long pinions are the result of a functional protein. A) Which gene is sex-linked? B) What are the genotypes of each parent and each type of offspring?
Step 1: Determine whether either of the genes are sex-linked. For this type of a question, if you arenât told, then the thing for which to look is whether when looking only at the offspring one of the phenotypes sorts out by sex.
In this example, Half of the resulting peacocks are metallic blue with short pinions and half the resulting peacocks are metallic blue with long pinions. Half of the resulting peahens are dull brown with short pinions and half the peahens are dull brown with long pinions.
This suggests what is sex-linked, why?
Step 2: Determine the correct sex chromosomes (if needed) for the species. Step 3: put down allelic place holders for each individual
Peacock Father: _/_ _/_ Peahens Mother: _/_ _/_
Peacock Boys: _/_ _/_ Peahens Girls: _/_ _/_
Step 4 Figure out which allele is functional for each gene. To do this, look at individuals that will be heterozygous for alleles from mom and dad. For sex-linked traits, that would be the homogametic sex (ZZ or XX). For autosomal traits, all offspring will be informative
Step 5: Fill in what you know for sure based on phenotype:
Peacock Father: _/_ _/_ Peahens Mother: _/_ _/_
Peacock Boys: _/_ _/_ Peahens Girls: _/_ _/_
Step 6: Apply Rules 1 & 2 to deduce the unknown alleles:
Peacock Father: _/_ _/_
Peahens Mother: _/_ _/_
Peacock Boys: _/_ _/_
Peahens Girls: _/_ _/_
What are the genotypes of each parent and each type of offspring? Parents genotypes :
Offspring genotypes:
A metallic blue-colored Indian blue peahen with long pinion feathers is crossed with a dull brown-colored Indian blue peacock with short pinion feathers. Half of the resulting peacocks are metallic blue with short pinions and half the resulting peacocks are metallic blue with long pinions. Half of the resulting peahens are dull brown with short pinions and half the peahens are dull brown with long pinions. Long pinions are the result of a functional protein. A) Which gene is sex-linked? B) What are the genotypes of each parent and each type of offspring?
Step 1: Determine whether either of the genes are sex-linked. For this type of a question, if you arenât told, then the thing for which to look is whether when looking only at the offspring one of the phenotypes sorts out by sex.
In this example, Half of the resulting peacocks are metallic blue with short pinions and half the resulting peacocks are metallic blue with long pinions. Half of the resulting peahens are dull brown with short pinions and half the peahens are dull brown with long pinions.
This suggests what is sex-linked, why?
Step 2: Determine the correct sex chromosomes (if needed) for the species. Step 3: put down allelic place holders for each individual
Peacock Father: _/_ _/_ Peahens Mother: _/_ _/_
Peacock Boys: _/_ _/_ Peahens Girls: _/_ _/_
Step 4 Figure out which allele is functional for each gene. To do this, look at individuals that will be heterozygous for alleles from mom and dad. For sex-linked traits, that would be the homogametic sex (ZZ or XX). For autosomal traits, all offspring will be informative
Step 5: Fill in what you know for sure based on phenotype:
Peacock Father: _/_ _/_ Peahens Mother: _/_ _/_
Peacock Boys: _/_ _/_ Peahens Girls: _/_ _/_
Step 6: Apply Rules 1 & 2 to deduce the unknown alleles:
Peacock Father: _/_ _/_
Peahens Mother: _/_ _/_
Peacock Boys: _/_ _/_
Peahens Girls: _/_ _/_
What are the genotypes of each parent and each type of offspring? Parents genotypes :
Offspring genotypes:
