determining genotype by test crosses? (1 Viewer)

[fallingstar]

Can anyone help me with this question from the "biology in focus" hsc textbook p152

q.5 A breeder of guinea pigs needs to find out if one of her brown guinea pigs is heterozygous or homozygous for hair colour. Albino guinea pigs have the genotype 'aa'. Guinea pigs that are not albinos may have the genotype 'AA' or 'Aa'. Explain how she might do this using a test cross to determine the genotype of her brown guinea pig.

?

 

[jeff.wong]

Can anyone help me with this question from the "biology in focus" hsc textbook p152

q.5 A breeder of guinea pigs needs to find out if one of her brown guinea pigs is heterozygous or homozygous for hair colour. Albino guinea pigs have the genotype 'aa'. Guinea pigs that are not albinos may have the genotype 'AA' or 'Aa'. Explain how she might do this using a test cross to determine the genotype of her brown guinea pig.

?

Breed the brown guinea pig with an albino guinea pig so

A? with aa

If all offspring is brown it means original brown is AA since it will be Aa Aa Aa Aa

If 1/2 turns out to be albino then original brown is Aa since the offspring possibilities are Aa Aa aa aa

 

[fallingstar]

thankyou