BIOLOGY NOTES GENETICS PART 5 PAGES 198-208, 212-217

1. BIOLOGY NOTESGENETICS PART 5 PAGES 198-208, 212-217

2. Standards: 4.6 _____ Use Mendel’s laws of segregation and independent assortment to analyze patterns of inheritance _____ Discuss observed inheritance patterns caused by various modes of inheritance, including dominant, recessive, co-dominant, sex-linked, polygenic, and multiple alleles _____ Analyze how heredity and family history can impact personal health 4.7 4.14

3. Essential Question: How do genes influence the variety of organisms that exist? 1.

4. Human Autosomal Disorders Autosome = chromosome pairs 1-22 which contain genes for characteristics not directly related to the ____ of the organism • Autosomal disorders can occur in any chromosomes except the _____ chromosomes sex sex

6. 2 recessive alleles hair • Albinism  • Cause: ________________ • Lack of pigment in skin, _____ , and eyes • Skin and eyes are extremely sensitive to _____ 2. Cystic Fibrosis • Cause: _________________ • Excess mucus in __________and digestive tract • Respiratory and pulmonary problems light 2 recessive alleles respiratory

8. 2 recessive alleles galactose 3. Galactosemia • Cause: _________________ • Inability to breakdown __________ which builds up in body • Mental retardation, eye and _____ damage 4. Tay-Sachs disease • Cause: ________________ • Lipid accumulation in brain cells • Death early in childhood. liver 2 recessive alleles

9. 1 dominant allele 5. Huntington’s disease • Cause: _______________ • Progressive destruction of muscles and nervous system • Destruction of muscles and _______ until death occurs nerves

10. II. Unique Patterns of Inheritance Mendelian Simple ___________ genetics predicts offspring and parents based on alleles that are only _________ or _________. The majority of organisms, however, are more ________ and show unique patterns of ___________. dominant recessive complex inheritance

11. 1 dominant • Incomplete Dominance = type of inheritance in which __ allele is not completely __________ over another • the heterozygote is a ______ between the two alleles (completely different heterozygote) blend

12. RR = Red RW = Pink WW = White RR * WW = RW (pink) e.g. flower color in 4o’clock plants ** since neither allele is more dominant over the other, each allele gets its own letter What type of human traits do you think show incomplete dominance (baby lab)? ** Lip shape, mouth size, size of eyes, eye spacing, hair type, ear size, nose size

13. 2 population B. Multiple Alleles = type of inheritance in which genes have more than __ alleles within a __________ • each individual can have only ___ alleles e.g. ABO Blood System 2 3 alleles = IA, IB, and i IAIA = type A blood IAi= type A blood IAIB = type AB blood IBIB = type B blood IBi= type B blood ii = type O blood (no antigens)

14. ii = type O blood * Who would be the universal donor? * Who would be the universal recepient? IAIB = type AB blood

15. phenotype express C. Codominance = type of inheritance in which both alleles contribute to the __________ • both alleles ________ themselves, but not as a ______ e.g. AB Blood Type, Checkered Chickens, Sickle Cell Anemia blend IAIA = type A blood (has only A antigens) IBIB = type B blood (has only B antigens) IAIB = type AB blood (has A and B antigens)

16. B = Black b = White Bb = checkered e.g. AB Blood Type, Checkered Chickens

17. traits 1 D. Polygenic Traits = type of inheritance in which ______ are controlled by more than __ gene e.g. eye color, hair color, skin color

18. traits chromosomes E. Sex-Linked Genes = type of inheritance in which genes with particular ______ are located on the sex _____________ (X or Y) • males are ____ while females are ____ • in males, any trait linked to the ___ chromosome will be ___________ even if they are recessive XY XX X expressed

21. allele X 1. Color-Blindness • caused by a recessive ______ on the ___ chromosome • 1 in 10 males have red-green colorblindness • 1 in 100 females have red-green colorblindness

22. XB = normal Xb = colorblind XBXB = normal female XBXb XBY = normal male e.g. XbXb = colorblind female XbY = colorblind male

24. allele X 2. Hemophilia • caused by a recessive ______ on the ___ chromosome • 1 in 10,000 males have the disease • in this disease, blood clotting enzymes are _______ • small bruises and cuts may cause excessive _________ even into death absent bleeding

26. e.g. What would be the chances of having a Hemophiliac son if XHXh * XHy?

27. III. Human Heredity chromosomes • Karyotype = a chart that shows all pairs of _____________ in order • taken during _______ when the chromosomes formed (during prophase) • humans have ___ chromosomes that are organized into ___ pairs • each pair has the same _____ of genes but may have different _______ mitosis 46 23 type alleles

28. mom dad 23rd • in each pair, one chromosome comes from _____ and one from ____ • sex chromosomes = the _____ set of chromosomes that determines the _______ of the human • ____ for males and ____ for females gender XX XY

30. homologous few D. Sex Chromosomal Disorders • Nondisjunction = during meiosis, ____________ chromosomes fail to separate meaning gametes with too ______ or too ____ chromosomes many

31. trisomy 3 1. Down’s Syndrome • also known as ________ 21 because there are __ #21 chromosomes • results in severe mental retardation 2. Klinefelter’s Syndrome (XXY) • have an extra ___ chromosome • prevents individuals from reproducing X

32. 1 X 3. Turner’s Syndrome (XO) • have only ___ sex chromosome which is an ___ • unable to develop sex organs at all