Chapter 14: Human Heredity (Genetics II)

1. Chapter 14: Human Heredity(Genetics II)

2. Thomas Hunt Morgan (1933) • Used fruit _________(Drosophila melanogaster) • Females had 8 paired chromosomes while males have 3 pairs and 1 mismatched pair

3. Why use flies? Fruit flies are ideal to use because: • _____ – many can be kept in a small space • ________________– breed in 4 days • 1 pair produces ~ _______________ • ________ life span – 14 days • ___ chromosomes per body cell

4. How is sex determined? • Sex Chromosomes – mismatched chromosomes that _________________ • In humans, ___ or ___ - Always a 50:50 chance of a boy or a girl with males determining sex of child • Humans have ____ chromosomes/body cell. Last two are sex chromosomes. ____ autosomes & ___ sex chromosomes

5. Sex Linkage • Morgan noticed that some traits in fruit flies were inherited _________________ in males than in females. ___________ seem to inherit certain traits w/ a greater frequency than females. P1: Wild type female X White eyed male F1: Wild Type F2: ___% Wild type ____% White males (All females & ½ (Only males) of the males)

6. How was the gene for eye color related to being a male? • Conclusion: The gene for eye color is carried on the ____________________. • _____ is shorter and has no corresponding gene for eye color.

7. Normal female Carrier female Female w/ trait Normal male Male w/trait

8. Crosses: Cross a carrier red-eyed female w/ a white eyed male. • PR: GR: • Cross a red eyed male w/ a carrier red eyed female. Y

9. Can a female have white eyes? • Cross a Carrier red eyed female with a white eyed male. PR: GR:

10. Sex linked traits in humans • Color blindness – can’t see certain _______Online TestAnother Test

11. Other Sexlinked traits • Hemophilia – ___________ blood clotting factors “bleeders” • Duchenne’s Muscular Dystrophy – ________________________ of skeletal muscle control • Severe combined Immunodeficiency (SCID)

12. Colorblindness Pedigree • Pedigrees - like a ______________ of a family’s genetic history. Traces a family’s genes

13. Roman numerals show each Generation

14. This pedigree chart shows inheritance of the gene that causes albinism (_______________________________ trait).

15. A pedigree chart for the inheritance of achondroplasia (ay-kon-druh-play-zhuh), a form of dwarfism. Dwarfism is a ________________________________trait

16. Karyotypes Diagrams or photo of how chromosomes are _____________ and which ones are present from an individual. Chromosome smear Karyotypes can be used to determine ___________________ in chromosome makeup.

17. A Normal female

18. A Normal Male

19. Down’s Syndromeor Trisomy 21

20. Klinefelter’s syndrome

21. Amniocentesis • Method of _________________ amniotic fluid w/ fetal cells. Can give _______ of child and also a ____________ is produced.

22. Nondisjuction • Involves a whole chromosome or an entire set of chromosomes that _______ to _____________ during meiosis. • Gametes may contain extra or too few chromosomes

23. If Sex chromosomes fail to separate properly • Turner’s Syndrome - ______________ • Sterile, underdeveloped, short, webbed neck • Low mental capacity • 1/2000 births • Klinefelter’ssyndrome – _______________ • Underdeveloped, sterile, female characteristics but is a male • 1/1000 births • _____________– Dead • need an X chromosome to survive • _________________– Triple female • normal mental capacity. Tend to be lighter than normal. Very passive. Are fertile • ______________– Triple males. • 1/1000. Very physical. Fertile. Tends to be more aggressive. 2% of convicts of violent crimes (disputed?)

24. If ______________ fail to separate • Trisomy 21 (or other type of trisomy) – aka; __________________ • Extra ______chromosome • Mild to serious mental deficiency • 1/800 births • Also found in primates OTHER TRISOMY CONDITIONS DO EXIST—22, 13, AND OTHERS

25. Extra #21 chromosome

26. Polyploidy • _____________ or sets of chromosomes fail to separate • ___________ in animals • In plants, leads to larger, hardier plants • 3N, 4N

27. How do female cells survive with an extra ____? X-inactivation- one chromosome is randomly switched ____ Condenses into a Barr Body X-Inactivation

28. Why don’t males have Barr Bodies? • Only have _______ that is active

29. Calico cats are _________ female Sometimes orange allele is switched off (black spots) Sometimes black allele is switch off (orange spots) Barr Bodies

30. Barr Bodies • Male cats can only be… • Orange • ______ • Black • ______ • Can not NORMALLY be both • Only one allele

31. Barr Bodies

32. Some genetic diseases

33. What are the different blood types? • ___ • ___ • _____(codominant) • ___

34. Universals? • O • Universal ___________ • AB • Universal _______________

35. Why does it matter?

36. What does it matter? • Blood transfusions! • If __________________ blood types are given, it can be FATAL! • Blood clumping

37. Blood Transfusions Donor Recipient

38. Is mom in trouble? • Dad is type AO • Mom is type BO • Baby is type O

39. Is mom in trouble? • Dad has type AB • Mom has type BO • Baby is type O

40. Match them up! • Julie—type AO blood • Hannah– type AB blood • Max—type OO blood • Mr. Smith—AO • Mrs. Smith—BO • Mr. Brown—AA • Mrs. Brown—AB • Mr. Jones—AO • Mrs. Jones—AA