# Help! watch

1. Ok i need help! with dihybrid crosses if you hjave one bird with CwCw x AfAf and another bird with CwCb x AfAs

Cw=white feathers
Cb=blackfeathers
Af=frizzy feathers
As=straight feathers
And all are codominant

what r the gametes and how do you cross them to find the offspring genotype and the offsrping phenotype
2. (Original post by flippinmentaljo)
Ok i need help! with dihybrid crosses if you hjave one bird with CwCw x AfAf and another bird with CwCb x AfAs

Cw=white feathers
Cb=blackfeathers
Af=frizzy feathers
As=straight feathers
And all are codominant

what r the gametes and how do you cross them to find the offspring genotype and the offsrping phenotype

Ok... colour coded to make things clearer

Parental gentotypes: CwCwAfAf and CwCbAfAs

Possible parental gametes:

CwAf and CwAf, CwAs, CbAf, CbAs

Offspring genotypes and genotypes

CwCwAfAf = white, frizzy feathers
CwCwAfAs = white, frizzy and straight feathers
CwCbAfAf = white and black, frizzy feathers
CwCbAfAs = white and black, frizzy and straight feathers (strange bird this 1)

Ok... all equally chance of forming of 25%
3. Thank you i get so confused when they sord questions like this one was...and im guessing the phentypic ratio would be 1:1?
4. 1 : 1 : 1 : 1

therefore there is a 1/4 (or 25%) chance of each phenotype
5. (Original post by flippinmentaljo)
Thank you i get so confused when they sord questions like this one was...and im guessing the phentypic ratio would be 1:1?
I think ti would be 11:1
6. Yeah well i had the right numbers.... i just obv cant cant... my brains turned to mush with all the biology....muh....thank you peeps!

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