Jump to content

Di hybrid cross


Recommended Posts

Does the f1 generation only occur when you have homozygous parents? Or can someone explain the concept of f1 and f2 generation?


What I know so far is that. Your giving to parents for e.g


p1 p2


Ww GG x ww gg < step 1


Gametes : WG WG wG wG wg wg wg wg Step 2


F1 ?... I'm confused here , what would be the f1 generation here..


What I do is simply do the following


Parent #1 can only give two gametes so which is ... WG wg and parent #2 can only give one which is wg.


Now I place them in the punnett square to get WG wg


wg WwGg wwgg



So did I do anything wrong? Like whats the f1 generation and f2 generation. I'm really confused because my book shows a two homozygous parents which go through f1 and f2 like




f1 Gen

f2 Gen




Link to comment
Share on other sites

I am quite new to genetics as well so forgive me if I am wrong but you can cross heterozygous parents as well. Parent 1 would give you WG wG and parent 2 would give you wg haploid gametes. So when you plug those into the punnett square you should get 2 different diploid cells; this will be your f1 generation.


Now if you cross f1 X f1 you take each of those diploid genotypes and work them into 4 different haploid gametes once again. Put those in a second punnett square and you will get the f2 generation phenotypes. It is common to get a 9:3:3:1 ratio but that is if both parents are homozygous. It will be a fraction of 16 (?/16). Hope this helps.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.