1. PROBABILITY
p. 181 and pp

2. heredity: transmission of characteristics from parent to offspring

3. probability: likelihood an event will happen and can be expressed as percentages, fractions, ratios, or decimals

4. What is the probability of getting “heads” when you toss a coin?

5. If you toss a coin 100 times how many times will it land on heads?

6. Formula for probability
Probability = # of times an event is expected to occur number of chances for the event to occur

7. EXAMPLE 1
You toss the coin 100 times and the coin lands “heads” up 49 times. What is the probability of getting a “heads”? 49 = 0.49 or 49% chance 100

8. EXAMPLE 2
There is a crate of 225 Black mice AND 25 white mice. What is the probability of picking up a white mouse. White mice appeared 25 times Total number of mice was 250 = 25/250 = 0.10 OR 10%

9. Tools of Probability
Monohybrid cross: cross between individuals that looks at one trait
Punnett square: diagram to predict the probability of inheritance of certain traits

10. Punnett Squares Place the parent genotypes in square: Aa x Aa
Parent I
Place the parent genotypes in square:
Aa x Aa
Match letters and fill in squares A a A AA Aa
Parent II a Aa aa

11. Mendel’s Ratios Genotype ratio- 1BB: 2Bb: 1bb 1:2:1 Phenotype ratio-
3 Black: 1 Brown
3:1

12. Genotype ratio
2:2 or 1: 1
Phenotype ratio
All black

13. Test Cross
Cross the dominant phenotype with a homozygous recessive (bb)
If you have recessive offspring then the individual must be heterozygous
Parent I
Parent I b b b b B Bb Bb B Bb Bb
Parent II
Parent II B b Bb Bb bb bb