1. Chapter 3 Human Genetics
Male = XY sex chromosomes
Female = XX sex chromosomes
Father determines the sex of baby.
How?
X or Y in the sperm
½ set of chromosomes has only one sex chromosome

2. 3-1 Multiple Alleles Alleles – different forms of the same gene
Blood types A, B, AB, O
Alleles A, B, O
Combinations
Blood type A AO or AA
Blood type B BB or BO
Blood type AB AB
Blood type O OO

3. Parent blood types
If one parent is blood type A and the other blood type O what are the possible children blood types?

4. Parent blood types
If a parent is blood type A and the other parent is blood type B what are the possible blood types of their children?

5. Blood types Universal donor? Universal receiver of blood? No antigens…
Have all the different antigens already in blood…

6. Sickle Cell Anemia Alters the shape of the red blood cells
A = normal allele for red blood cells
S = sickle cell allele for red blood cells
AA = normal blood type
AS = carrier of sickle cell (1/2 of cells are normal)
SS = sickle cell disease

7. Twins Identical twins Fraternal twins
Same egg and same sperm = same DNA
Have to be the same sex (two sisters)
.5 % of total population
Fraternal twins
Different egg and different sperm = diff DNA
Same sex or different sex (two brothers or a brother and sister)

8. Sex-linked traits Traits that are carried on the X chromosome
Can mothers pass traits to sons?
Can fathers pass traits to sons?
Can mothers pass traits to daughters?
Can fathers pass traits to daughters?

9. Sex-linked Traits Hemophilia
“bleeder’s disease”
blood clots abnormally slowly or not at all
Ryan White died in 1990 from hemophilia, contracted AIDS from a blood transfusion, which is necessary for hemophiliacs when they bleed from injuries often.
Royal family has a history of hemo… page 68
QEII does her line have H… in it today?

10. Sex-linked Traits Hemophilia
Colorblindness – can’t distinguish between colors
Male patterned baldness

11. Karyotype
Shows the size, number, and shape of all the chromosomes in an organism
47 chromosomes
Trisomy chromosomes in a pair
Down Syndrome
Amniocentesis – test for down syndrome

12. Ethical Questions Do you support abortion?
Would you abort a Down Syndrome child?
Does the state have the right to force a couple to abort an unborn handicap child?
Would you want to genetically engineer your child?
Should it be helping people who are very sick to kill themselves?

13. Human Genetic Disorders
Amniocentesis – removal of small amount of fluid from sac that surrounds the baby (baby cells are in the fluid – test done between weeks
Other tests can be done at weeks CVS
No cures for genetic disorders WHY?
1982 – doctors tested a drug that was to change the cells of Sickle Cell page 71
1989 – identifies gene responsible for cystic fibrosis and changed the gene in the cell and it became normal???

14. Down’s Syndrome 1:700 births Most common syndrome 1866 JL Down
Flat broad hands
Flat bridge of nose
Flat space between 1st and 2nd toe

15. Ethical Questions about Genetic Disorders
Can we detect genetic disorders?
Can we cure genetic disorders?
What do we do if we can’t cure the disorder?
ABORTION
TAXPAYERS PAY TO KEEP THESE CHILDREN
INSURANCE PRICES ???
SOCIETIES COST ???
IS THIS SCIENCE OR RELIGION OR MORALS?

16. Morals Definition – the rules a society lives by
What morals do you live by?
Make a list of what rules you live by.
Put the things that are good on the right.
Put the things that are wrong on the left.

17. Vocabulary Karyotype Incomplete Dominance Multiple Alleles
Sex-Linked Traits
Pedigree

18. Terms Karyotype - pairing of chromatids Nondisjunction
Occurs during meiosis when chromosomes do not separate properly
Pedigree shows members of a family
Amniocentesis - tests fluid around the baby for genetic disorders
Codominant – capital letters for all alleles

19. Search For The Genetic Code
DNA molecules= basic substances of heredity
DNA stores and passes genetic information
The discovery of DNA was most important discovery of 20th century

20. Review questions Name the 4 blood types
How many different alleles are there for blood type?
Name the two different arrangements of alleles for blood type A
Name the most uncommon type of blood
Name a blood type that has two different antigens.

21. Review Questions
What do we call a picture that shows all your relatives and who had a specific disorder?
What gender are you if you have an XY chromosome?
Who is the universal donor for blood?
Describe what a sickle cell anemia blood cell looks like?

22. Review Questions
Can a sickle cell father pass the disease on to his son?
Name 3 diseases that are sex-linked traits.
What does it mean when a trait is a sex-linked trait?
Describe what a sickle cell anemia blood cell looks like?
What do we call the test that removes fluid from next to the baby and does a karyotype?

23. Make a Baby Lab Read directions Only father flips for gender of baby
Record an H or T depending on the flip of the coin
Record the genotype from the key
Record the phenotype from the key