2. Genetics The Study of Inherited Characteristics Ch 10.1 and Ch12

3. Meiosis in the Gonads makes gametes: Sperm Meiotic cell division Egg

4. Chromosome DNA Code for traits

5. Gene Segments of DNA Segments of DNA Code for a trait Code for a trait Hair Color Eye Color

6. Gene Segment For Hair color

7. Trait Characteristic Feature Variations in a population

8. Dominant Trait “Dominates” “Dominates” Shows in the outward appearance Shows in the outward appearance Even when recessive trait is present Even when recessive trait is present Bb Bb BB or Bb

9. Recessive Trait “hidden” May be masked by a dominant trait b Bb Albinism bb

10. Alleles Letters of the alphabet Code for a trait One from father One from mother

11. Dominant Allele: Upper case letter of the alphabet Upper case letter of the alphabet Codes for dominant traits Codes for dominant traits Recessive Allele: Lower case letter of the alphabet Codes for recessive traits

12. Chromosomes in Nucleus Gene Segments For a Trait= “A” or “a”

13. Monohybrid Cross Cross for one trait Cross for one trait Example: Example: Hair color Hair color Bb BBBb B BBBb Punnet Square

14. F1 Generation Genetic Cross= Genetic Cross= Mating Mating F1= F1= Children Children 1 st “filial” generation 1 st “filial” generation Parents Bb BBBBb BBBBb

15. 2 nd Filial Generation- F2 Children of the cross between the children of an F1 Children of the cross between the children of an F1 “Incest” among F1 “Incest” among F1 Only after pure x pure Only after pure x pure F1= F2= F2= BB bBbBb bBbBb BbBBBBb bBbbb

16. Phenotype Outward appearance Outward appearance Trait that is shown Trait that is shown Bb looks brown (has “b” =white allele) Bb looks brown (has “b” =white allele)

17. Genotype Allele set Allele set True genetic makeup of the chromosome True genetic makeup of the chromosome Bb

18. Homozygous: Pure condition Pure condition 2 same case alleles 2 same case alleles BB= dominant BB= dominant bb= recessive bb= recessive Heterozygous: Hybrid condition 2 different case alleles Bb Bb appears dominant

19. Mendelian Genetics Review: See Encarta CD-ROM See Encarta CD-ROM

20. Dihybrid Cross Cross with Cross with two traits two traits Example: Example: 1. Hair Color 2. Eye Color 2 types of alleles parents ChildrenChildrenChildrenChildren ChildrenChildrenChildrenChildren ChildrenChildrenChildrenChildren ChildrenChildrenChildrenChildren

21. Codominance “Incomplete” dominance “Incomplete” dominance Hybrid is a blend of traits Hybrid is a blend of traits Example: Example:RR=red Rr=pink rr=white Pink Carnation

22. Multiple Alleles More than one type of allele for a trait More than one type of allele for a trait Example: Example: Blood Type TYPES: I A I A, I A i A I A I A, I A i I B I B, I B i B I B I B, I B i I A I B AB I A I B ii O ii

23. X-Linked Traits Sex-linked Sex-linked Trait in on the sex chromosome Trait in on the sex chromosome XX= XX= Female Female XY XY Male Male Ex:Red & white eyes Ex:Red & white eyes Female= XX Add eye trait= RR Rr X R X R or X R X r rrXrXrrrXrXr Male= XY Add eye trait= Rr X R Y or X r Y “Y” is empty

24. Karyotype

25. Chromosome Number Different # for different species Different # for different species Full set = 2N=Diploid Full set = 2N=Diploid N= N= # pairs # pairs 1 pair from mother 1 pair from mother 1 pair from father 1 pair from father Humans= 23 pairs or Humans= 23 pairs or 46 total 46 total Homologous Chromosomes are the sets of each pair

26. Autosomes & Sex Chromosomes Autosomes = # 1- 22 for all traits except sex Sex chromosomes= Pair # 23 XX(female) or XY(male)

27. Down Syndrome= 3 of #21

28. Klinefelter’s = XXY

29. Pedigree Charts Male = Male = Female= Female= Sexual Union= Sexual Union= Offspring= Offspring=

30. Pedigree Chart -Cystic Fibrosis

31. Mutation Change in DNA code Change in DNA code Caused by: Caused by: 1. Chemical damage 2. Errors in Replication 3. X-ray damage 4. UV damage A T GCGC A to A G C

32. Mutation Changes in the DNA code Changes in the DNA code = Changes in the final proteins made = Changes in the final proteins made =Changes in the organism =Changes in the organism