Question

if I had Dd, Dd, dd, dd what is the phenotypic ratio?

Answer 1

The phenotypic ration would be 1/2 and 1/2. The D is dominant and the d is recessive tso the Dd offspring will express the D allele and the dd ones will express the d allele. And you will have half offspring with a D phenotype and he other half with a d phenotype.

Answer 2

Thanks to the great @LFDV_nico, because he's sitting next to me and wanted to answer too :)

Answer 3

@MagaliH Like I had DD,Dd,Dd,dd the phenotypic ratio is 3:1... I am confuse how to write if it is 50%

Answer 4

Well, this is 1:1 so. I don't know how to write it differently. You're making me wonder now ;)

Answer 5

if I had Dd, Dd, dd, dd the genotypic wil be 0:2:2 but I don't know how to write the phenotypic ratio

Answer 6

I understood it well.
The phenotypic ratio for this case is nothing but 1:1, I'm sure of my answer now.

Answer 7

Can you explain how to get it?

Answer 8

So if it is DD,Dd,Dd,dd what is the phenotypic ratio? Since the genotypic is 1:2:1

Answer 9

@MagaliH

Answer 10

For Dd Dd dd dd, it's 1:1
For DD Dd Dd dd it's 3:1
You only have two phenotypic possibilities, while you have three genotypic possibilities.
Genotypic possibilities : dd, Dd (and its alternative dD) or DD
Phenotypic possibilities : D expressed or d expressed

The ratios are written in function of the number of representants of each possibility.

For Dd Dd dd dd, the genotypic ratio is 2:2:0 (so 1:1:0) and for DD Dd Dd dd it's 1:2:1. Have you understood why ?

Answer 11

No @MagaliH

Answer 12

Yes I know that at @nincompoop I understand the phenotype, genotype and genotypic ratio... But when it comes to phenotypic ratio I am confuse @MagaliH

Answer 13

Ok. So here I come again.

@nia_mae Look at my previous message. To know the genotypic ratio, you have to know all the possibilities, in your exemple, there are three possibilities (DD, dd and Dd). The ratio will be written like so :
number of representants of the DD genotype:number of reprensentants of the Dd genotype:number of reprensentants of the dd genotype

This is the same for the genotypic. Your have two different possibilties, and you have to count the representants of those possibilities.

Answer 14

*PHENOTYPIC

As you already know, DD = D phenotypes, Dd = D phenotype and dd = d phenotypes. So DD and Dd will give the same phenotypes (there are only two possibilities for phenotypic).

Answer 15

So if I had dd,dd,dd,dd the genotypic will be 0:0:4 and the phenotypic will 4? @MagaliH

Answer 16

You're right for the genotypic. For the phenotypic, it will be 0:4, because there are 0 representants of the D phenotype.

Answer 17

Ok... I see, I understand it a little bit now

Answer 18

You have some other examples ?

Answer 19

Nope, but I will appreciate if you can teach me some @MagaliH

Answer 20

Ok, so imagine you have a gene which have two alleles A and a. The 10 offsprings of a generation are described like that :
AA, Aa, aa, aa, aA, AA, aA, aa, aA, Aa.

(I don't know if it's even genetically possible to get this kind of genration, but let's imagine this is real).
Give me the genotypic and phenotypic ratio.

Answer 21

Genotypic ill be 2:5:3 @MagaliH

Answer 22

Yaaaay ! And the phenotypic one ? Remember that A is dominant (even if I'm sure you remember).

Answer 23

Trying to figure out lol @MagaliH be patient on me... ;-)

Answer 24

Is 5:3

Answer 25

Is it 7:3?

Answer 26

Take you time, I've got the whole night for me (I'm staying at my university).
Hum, nope. Try again. Do you need a clue ?

Answer 27

Yes please @MagaliH

Answer 28

I didn't see your next answer, YOU'RE RIIIGHT

Answer 29

So my answer 7:3 is right?

Answer 30

Yes it is !

Answer 31

Give me another example please....

Answer 32

Ok, let's start :
aa, AA, Aa, aA, Aa, aa, aa, AA, aA, aa, AA, Aa

There a 12 offsprings now.

Answer 33

Genotypic will be 4:3:5 and phenotypic will 8:4

Answer 34

And that's a victory ! Congratulations :)

Answer 35

Yay! Awesome! Thank you for teaching me!

Answer 36

Thanks to you, you've done a great job :)

Answer 37

@MagaliH so if I had DD,DD,D,Dd genotypic is 2:2:0 phenotypic is 4:0

Answer 38

DD,DD,Dd,Dd

Answer 39

Exact :)

Answer 40

The phenotype is D=dimples and the genotype will be DD,Dd

Answer 41

Yeah, for a same phenotype, there could exist several genotypes.

Answer 42

Later, gonna proceed in word problem about pun net square... Gonna try to answer it first... Please help me check my answers later... I will appreciate it... @MagaliH

Answer 43

I will for sure, mention me and I will come (if I'm not sleeping or running in the subway's corridors).

Answer 44

Sure... Thank you