1. Heredity Heredity by Brainpop

2. I. Heredity & Genetics parent to offspring oThe passing of traits from parent to offspring genes oTraits are controlled by genes

3. II. ALLELES FORM oONE FORM of a gene one oSex cells have one two oBody cells have two forms or ALLELES for a single gene dominant oOne may be dominant over another.

4. III. DOMINANT AND RECESSIVE mask oDominant will always be expressed and will “mask” recessive dominant oA recessive trait can only be expressed if there are no dominant alleles present.

5. oExample dominant oExample: Eyecolor—Brown color is dominant and blue is recessive.

6. capital lower caseDominant alleles are represented with a capital letter, recessive with a lower case letter.

7. IV. GREGOR MENDEL father o“father of genetics”

8. peas oMendel worked with peas

9. V. PROBABILITY ochance ochance something will happen 50% oEx: heads or tails on a coin is 50% (1/2 chances) accurate omore accurate with more trials

10. Why is it that if a couple has 2 children, they don’t always have one boy and one girl? 2 is a really small trial #…so won’t always “see” the ratio!

12. VI. Using a Punnett Square oUsed to predict probability of traits otrait is given TWO letters, one for each allele.

13. o“Purebred” =BB or bb. o“heterozygous”(hybrid). Bb GENOTYPE = Gene Combinations located on chromosomes

14. PHENOTYPE oThe PHYSICAL trait =PHENOTYPE. oBlue Eyes.

15. Incomplete dominance Heterozygous expresses a different phenotype

16. Multiple alleles - Blood type 3 alleles, codominance A,B,o

17. 4 blood types from 3 alleles AA or Ao= type A BB or Bo= type B AB = type AB oo = type O

18. Polygenic inheritance = many genes for one character.

19. SEX-LINKED and SEX INFLUENCED TRAITS

20. SEX CHROMOSOMES CAN CARRY OTHER GENES TOO = _________________ SEX LINKED TRAITS

21. Sex chromosomes can carry other genes Y-LINKED GENES: Genes carried on Y chromosome EX: Hairy pinna _______ genes only show up in __Y linked males.

22. Sex chromosomes can carry other genes X-LINKED GENES: Genes carried on the X chromosome EX: _____________ _____________ _________________________ Hemophilia Colorblindness Duchenne Muscular Dystrophy

23. SEX INFLUENCED TRAITS Genes ___________ on sex chromosomes BUT affected by ____________ of individual with gene not carried sex hormones

24. PEDIGREE CHART Normal Male = Normal Female = Has trait =

25. CARRIER Individual with one copy of a recessive autosomal allele Carriers DON’T SHOW the trait themselves but can pass it on to their offspring NORMAL DEFECTIVE

26. CHROMOSOMES

27. DNA Nucleic acid made of nucleotide subunits A T G C Found in nucleus Carries the genetic code in its sequence

28. DNA can appear in 2 forms Spread out in nucleus as _____________ in NON-DIVIDING cells Scrunched into bundles as ________________ in DIVIDING cells CHROMATIN CHROMOSOMES

29. ________ PROTEINS maintain shape of chromosome Histone

30. Cancer cells Don’t stop dividing ___________ damage DNA Ex: Radiation, cigarette smoke, chemicals in environment Carcinogens

31. CANCER

33. Chromosome structure ____________ 2 identical arms ____________ constricted area holds chromatids together __________________ PAIR 2 of each chromosome (one from mom; one from dad) CHROMATIDS CENTROMERE HOMOLOGOUS

34. CHROMOSOME NUMBERS Each species has a characteristic number of chromosomes HUMANS have 46 chromosomes (23 pairs )

35. DIPLOID & HAPLOID Cells with 2 copies of each chromosome are _______________ (one from mom; one from dad) All body cells Cells with only one copy of each chromosome are ____________________ Sperm and egg 1n + 1n = 2n egg + sperm new organism DIPLOID2n HAPLOID1n

36. KARYOTYPES ________ = picture of organism’s chromosomes KARYOTYPE

37. Chromosomes that determine the sex of an organism = _________________________ All other chromosomes = _________________ Sex chromosomes autosomes Humans have two sex chromosomes X y

38. A KARYOTYPE can tell the sex of an organism In humans XY is a male

39. In humans XX is a female

40. Guess who? XY

41. You can’t judge a critter by its chromosomes This critter has 54 chromosomes

42. Corn has 10 pair of chromosomes

43. Snails have 18 pairs of chromosomes

44. A mouse has 40 chromosomes

45. Nondisjunction Chromosomes fail to separate during meiosis gametes may have too few or too many chromosomes Disorders: –Down Syndrome – three 21 st chromosomes –Turner Syndrome – single X chromosome –Klinefelter’s Syndrome – XXY chromosomes 45

46. Eric has Down’s Syndrome 1 in 750 births Has extra #21 chromosome Mental retardation

48. Down’s syndrome (trisomy 21) Simian line on palm Eye fold

49. Down’s syndrome (trisomy 21) Most common chromosomal abnormality 50% have heart defects Mental retardation Risk increases with age of mom

50. Patau syndrome (trisomy 13)

51. 1 in 7000 births (rare)

52. Patau syndrome (trisomy 13) Cleft lip & palate Eyes too small or missing

53. Patau syndrome (trisomy 13) Low set ears Polydactyly

54. TURNER’s SYNDROME XO- only 1 X, no Y Short stature Immature ovaries heart problems hearing loss decreased mental ability

55. Turner Syndrome Normal uterus, tubes and ovaries and ovaries Non-functional Ovaries

56. Kleinfelter syndrome XXy

57. Kleinfelter syndrome 1 in 1000 births Male = XXy Aslight decrease in intelligence Small testes/can’t have children

58. Xyy syndrome Xyy males Taller, more aggressive