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

2. Standards:
_____ 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
5.6
5.7
5.14

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

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. 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
2 recessive alleles
hair
light
2 recessive alleles
respiratory

8. 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.
2 recessive alleles
galactose
liver
2 recessive alleles

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

10. II. Unique Patterns of Inheritance
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 ___________.
Mendelian
dominant
recessive
complex
inheritance

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

12. e.g. flower color in 4o’clock plants
RR = Red
RW = Pink
WW = White
RR * WW = RW (pink)
** 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. 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
population 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. * Who would be the universal donor? * Who would be the universal recepient?
ii = type O blood
IAIB = type AB blood

15. 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
phenotype
express
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. e.g. AB Blood Type, Checkered Chickens
B = Black
b = White
Bb = checkered

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

18. 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
traits
chromosomes XY XX X
expressed

21. 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
allele X

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

24. 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
allele X
absent
bleeding

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

27. III. Human Heredity
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 _______
chromosomes
mitosis 46 23
type
alleles

28. 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
mom
dad
23rd
gender XX XY

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

31. results in severe mental retardation
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
trisomy 3 X

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