Probability
Probability = the likelihood a particular event will occur
1. # of times the event occurs
# of trials
2. Previous events DO NOT affect future outcomes
3. The larger the number of trials the more accurate probability you will have. (Closer to
actual population probabilities)
Ratios- Relationship between two characteristics.
1. Phenotypic ratios- The physical characteristics of an organism presented as a ratio
a. Dominant : Recessive
b. Ex: Blue (B) is dominant to Green (b)
B
b
B BB
Bb
b Bb
bb
3:1
75% blue and 25% green
2. Genotypic ratios- The alleles for a trait in a population presented as a ratio
a. Homozygous Dominant: Heterozygous: Homozygous Recessive
b. BB:Bb:bb
c. Ex: Blue (B) is dominant to Green (b)
B
b
B BB
Bb
b Bb
bb
1:2:1
25% Homozygous Dominant, 50% Heterozygous and 25% Homozygous recessive