1. Genetics!!!
Seminar

3. What Can Karyotypes Tell Us?
A karyotype is a picture of a person’s chromosomes.
The gender of a person.
If they have a CHROMOSOMAL disorder.

4. Chromosomal Disorders
Down’s Syndrome (extra 21st chromosome)
Klinefelter’s (extra X for boys, XXY)
Turner’s (only 1 X for girls, XO)

5. What disorder is this?
Turner’s Syndrome
Only 1 X Chromosome

6. Klinefelter’s Syndrome
What disorder is this?
Klinefelter’s Syndrome
XXY (Male)

7. What disorder is this?
Down’s Syndrome
3 Chromosomes on 21st pair

8. http://www.youtube.com/watch?v=07MjCIEUcPk (until about 1:35)
Gregor Mendel
THE FATHER OF GENETICS
(until about 1:35)

9. Genetics Vocabulary Allele?
An alternative form of a gene for one trait.
Example: Trait=eye color
Allele=brown eyes, blue eyes, green eyes, etc.

10. Genetics Vocabulary Genes?
Segments on chromosomes that determine what we look like.

11. Genetics Vocabulary Genotype?
The actual code that alleles or genes possess (Tt, TT, tt).
Phenotype?
The observable form of a gene (brown, red, short, tall).

12. Genetics Vocabulary Homozygous?
Two of the same alleles for one trait (TT, tt).
Heterozygous?
Two different alleles for one trait (Tt).

13. Genetics Vocabulary Dominant?
The trait that masks or overpowers the other.
You only need one copy for the trait to be seen.
Recessive?
The trait that can be masked or overpowered.
You need two copies for the trait to be seen.

14. Complete Dominance
In pea plants, round (R) is dominant to wrinkled (r). What would happen if you crossed the following (F1):
What is the genotype ratio?
R R r Rr Rr
What is the phenotype ratio? Rr Rr

15. Complete Dominance
In pea plants, round (R) is dominant to wrinkled (r). What would happen if you crossed two heterozygous round plants?
What is the genotype ratio?
R r R r RR Rr
What is the phenotype ratio? Rr rr

16. Incomplete Dominance
In snap dragon flowers, white is incompletely dominant to red. What would be the result if a red and white snapdragon were crossed?
What is the genotype ratio?
R R W RW RW
What is the phenotype ratio? RW RW

17. Incomplete Dominance
What is the chance that you could get a white flower if a pink flower and a red flower were crossed?
What is the genotype ratio?
R W R RR RW
What is the phenotype ratio? RR RW

18. Co-dominance
In cows, red is co-dominant to white (roan). What would be the result if you crossed two roan cows?
What is the genotype ratio?
R W R W RR RW
What is the phenotype ratio? RW WW

19. Co-dominance
In cows, red is co-dominant to white (roan). What is the chance of getting a roan cow from two red cows?
What is the genotype ratio?
R R R RR RR
What is the phenotype ratio? RR RR

20. Blood Types
If John has blood type O and Mary is homozygous for blood type A, what are the possible blood types for their children?
What is the genotype ratio?
i i IA
IAi
IAi
What is the phenotype ratio?
IAi
IAi

21. Blood Types
Their daughter Alexandria marries and has children with Roberto who is blood type AB. What are the possibilities for their children?
What is the genotype ratio?
IA i IA IB
IAIA
IAi
What is the phenotype ratio?
IAIB
IBi

22. Sex-Linked
Colorblindness is a sex-linked trait. James is color-blind and marries Brittany who is a carrier. What is the chances they would have color blind child?
What is the genotype ratio?
Xb Y XB Xb
XBXb
XBY
What is the phenotype ratio?
XbXb
XbY

23. Sex-Linked
If Tina is color blind and has children with Rayquan (who is normal), what is the chances they will have a color blind son?
What is the genotype ratio?
Xb Xb XB Y
XBXb
XBXb
What is the phenotype ratio?
XbY
XbY