Hey there. Ive typed up a couple to use as examples using the brown hair. You must take into account the recessive and dominant traits, as this could range your answer being different.
A phenotype is the result of a genotype, which is the result of 2 alleles. Say if both parents were HOMOZYGOUS for brown hair, with their genotype would be BB, BB. Use a trick called a punnet square to answer this;
_|B |B |
B|BB|BB| <-- not the best punnet square, but the top row shows the first parents
B|BB|BB| genotype (BB) and the side shows the second's. (BB) The cross of this
shows all the children will have brown hair, as inherited from each parent.
If the Mother had HOMOZYGOUS brown hair (BB), and the father had HETEROZYGOUS brown hair (Bb) the results would be 100% Brown hair too, because the brown hair gene (B) is dominant over the non brown hair gene (b). Below;
_|B |B |
B|BB|BB| <--- this shows the cross gives a 50% chance to be Homozygous for brown
b|Bb|Bb| hair but 50% heterozygous for brown hair, but carrying a non- brown hair
gene.
If we cross 2 heterozygous parents, the results are shown:
_|B |b |
B|BB|Bb|
b|bB|bb| <----- This shows the child has a 75% chance of having brown hair (either
(BB or bB, Bb) and 25% of being non-brown (bb)).
This can be used in any gene cross, but you must keep in mind that one gene will be dominant and one will be recessive. I used the brown hair gene as an example here, as I don't know whether it may be dominant or recessive to other hair colours.
Also, if you were after a global statistic, I wouldn't know. I hope this helps you.
Fletch
For a punnet square counting only one trait:
Count all of the ones that have a capital letter. This is the number with the dominant phenotype. All of the ones with both lowercase letters are the recessive phenotype.
The Genotypic ratio of Dihybrid cross is 1:2:2:4:1:2:1:2:1
this ratio also called as dihybrid ratio.
the phenotipic ratio is:
9:3:3:1
and i dnt know the genotipic!!
1 homozygous dominant: 2 heterozygous: 1 homozygous recessive
1:2:2:4:1:2:1:2:1
9:3:3:1
1:2:1
The phenotypic ratio resulting from a dihybrid cross showing independent assortment is expected to be 9:3:3:1. This ratio is obtained when two heterozygous individuals are crossed for two traits that are independently inherited. The ratio represents the different combinations of phenotypes that can arise from the cross.
Because in heterozygotes, both alleles are transcribed and translated.
dihybrid cross
dihybrid cross
1:1:1:1:1:1:1:1 ratio is the expected outcome of a heterozygous (BbGgCc) and a homozygous recessive (bbggcc) cross.
The expected genotypic ratios for a dihybrid cross is 9:3:3:1, and for a monohybrid cross is 1:2:1.
representation of genotypes of a pair of contrasting traits of a character in the form of ratio is referred as genetic ratio. in this ratio the three different genotypes are represented- homozygous dominant genotype:heterozygote genotype:homozygous recessive genotype in case of a monohybrid cross ( either normal cross,reciprocal crosses of Mendel or back cross or test cross ratios) and for dihybrid crosses- dominant genotype:recombinant genotypes:recessive genotypes are represented. For instance monohybrid genotypic ratio is 1:2:1 and back cross/test cross ratio-1:1 For dihybrid genotypic ratio 1:2:2:4:1:2:1:2:1 It may differ in different cases according to T.H.Morgan.Bateson, punnet, Garrod etc.
becouse you touch yourself at night.
The genotypic ratio of a cross of Aa and Aa is: one AA, one aa, and two Aa. Or 1:2:1
monohybrid cross deals with one genotypic trait whereas the dihybrid cross deals with two traits being crossed to see the possible genotypes.
Dihybrid cross
The phenotypic ratio resulting from a dihybrid cross showing independent assortment is expected to be 9:3:3:1. This ratio is obtained when two heterozygous individuals are crossed for two traits that are independently inherited. The ratio represents the different combinations of phenotypes that can arise from the cross.
Because in heterozygotes, both alleles are transcribed and translated.
dihybrid cross
dihybrid cross
1:1:1:1:1:1:1:1 ratio is the expected outcome of a heterozygous (BbGgCc) and a homozygous recessive (bbggcc) cross.
dihybrid cross