3.21a Genetic probabilities

1. We're predicting the probabilities of offspring through monohybrid crosses. 
2. Monohybrid crossing- crossing which consists of only one gene. 
3. Let's consider the cross between a red petal plant and a white petal plant. 
4. The genotype of the red petal plant is RR and the genotype for a white petal plant is rr. 
5. This makes the R>r. In other words, red is dominant to white. 
6. The next stage involves meiosis which includes the production of the pollen grains and the ovules. 
7. The gamete will contain only one of the two alleles. 
8. For instance, in the production of the pollen, 1/2 the gametes will have the R and the other half will have the other big R as its an equal chance. 
9. In the production of the ovules we need to separate the alleles so that we only have 1 of the pair of alleles in each gamete. half of the ovules would have little r and the other half would have little r. 
10. Then we consider random fertilization.