1. Biology Law of Heredity Ms. Yang 02.07.2013

2. Objectives SWBAT… 1.Set up and solve a Punnett square 2.Review key concepts of heredity. Catalyst Turn the following into a ratio: 1.6 white eyes to 7 red eyes 2.9 pink to 8 purple to 6 blue 3.10 oranges to 10 apples to 10 bananas Date: 02/06/2013

3. Catalyst Response 1.6 white eyes to 7 red eyes 2.9 pink to 8 purple to 6 blue 3.10 oranges to 10 apples to 3 bananas to 3 grapes to 10 peaches 6:7 9:8:6 10:10:3:3:10

4. Group Roles RoleDuties Manager* Reads directions and keeps group on task Recorder* Turns in worksheet and makes sure everyone agrees on answers Reporter* Presents answers to class Technician* Gets materials and asks questions to teacher or other groups. It is EVERYONE’s duty to contribute to the group and learn the material!

5. Model 3 Send TECHNICIAN to get penny. Complete Model 3.

6. Model 3 RR rr Rr Rr Possible combination of alleles: Rr Phenotype: round Possible combination of alleles: RR, Rr, rr Phenotype: round, round, wrinkled

7. Model 4

8. Mendel’s Law of Heredity Review Notes!

9. Crossed pea plants Tested for different traits Mendel’s Pea Experiments

10. Why pea plants? –Easy to grow –Don’t take up a lot of space –Grows fast –Easy to “mate” together –Makes lots of offspring (seeds)

11. Mendel’s Pea Experiments Parents First generation, Offspring of Parents Second generation, Offspring of F1 mating with another F1

12. Mendel’s Conclusions Heredity = traits are transmitted from 2 parents to their offspring Trait = a characteristic that is based on genetics Hybrid = offspring of parents that have different forms of a trait Purebred = offspring of parents have the same form of a trait

13. Genetics Offspring get two copies of genes for a trait ( ONE FROM MOM, ONE FROM DAD ), sometimes one copy dominates over the other copy.

14. Genetics Gene = section of chromosome that tells cell what to do Allele = a variant of a gene Dominant = an allele that dominates over the recessive allele, only need one copy to be expressed Recessive = an allele that gets masked if a dominant allele is paired with it, must have two copies to be expressed

15. Genetics Homozygous = 2 identical alleles for a trait Heterozygous = 2 different alleles for a trait Genotype = combination of alleles Phenotype = expression of the genotype, the way the genotype is expressed

16. Monohybrid Cross Making a cross for ONE trait A Punnett square for a MONOHYBRID CROSS looks like:

17. Steps to solve Punnett Square Cross 1.What are the parent alleles? 2.What size Punnett square? 3.Where do the parent gametes go?

18. Example #1 In pea plants…. Tall (T) is dominant over short (t) Make a cross between Homo tall X Homo short TTtt

19. GENOTYPE _____ PHENOTYPE _______ _____ of the offspring ____ % ___/4 will be _______ TT t t T tT tT t T tT t T tT t TALL ALL 100 4 TALL

20. _____ of the offspring ___/4 or ____ % will be _________ GENOTYPES _______ PHENOTYPES _______________ WHAT ARE THE POSSIBLE… Tt 4 100 4 tall Tall

21. Example #1 In humans…. Brown eyes (B) is dominant over blue eyes (b) Make a cross between Hetero X Hetero Bb

22. Try the Cross! Bb B b B BB BB b B bB b b bb b

23. _____ of the offspring ___/4 or ____ % will have _________ GENOTYPES _______ PHENOTYPES _______________ _______ _______________ WHAT ARE THE POSSIBLE… _____ of the offspring ___/4 or ____ % will have _________ Bb BB 25375 1 3 brown eyes 1 blue eyes bb Blue eyes Brown eyes