3.20 predict probabilities of outcomes from monohybrid crosses

From mono-hybrid cross diagrams there are four outcomes, some times some of the out comes are the same.

To work out the probability of a child inheriting a genotype, you see how many times it comes up and divide it by 4 then times by 100 for a percent.

To work out phenotype probability you work out how many times they will express a characteristic and divide it by four then times by 100 for a percent.

If we say in this diagram the B represents brown hair and b represents red hair

(The capital letter is always dominant)

scienceaid

The likely hood of the chlid carrying one allele for brown and one for red (Bb) is two out of four:

2/4= 0.5

x100= 50%

The likely hood of the child having red hair (red hair is recessive so they both have to be red (bb)) is two out of four: also 50%