1. Do Now
Get out homework; turn in understanding cancer; Get out Codon Table
Why is cancer more common in older people?
The addition of one or more nucleotide base pairs into a DNA sequence is a(n) __________ mutation. How does this affect the protein made during protein synthesis?

2. Mendelian Genetics

3. Who is Gregor Mendel? Father of Genetics
Raised in a poor farming family; joined the monastery to get an education
Became the gardener of the monastery
Noticed differences between plants; particularly pea plants
Father of Genetics

4. Why peas?
1. Cheap

5. Why peas?
2. Peas grow very fast

6. 3. Peas are easy to manipulate during reproduction
Why peas?
3. Peas are easy to manipulate during reproduction

7. 4. Peas have many traits to examine
Why peas?
4. Peas have many traits to examine

8. Anatomy of a Flower Stamen = Male Pistil = Female Petal Stigma
Anther: Pollen
Style
Filament
Ovary: Eggs
Stamen = Male
Pistil = Female

9. Plant fertilizes it own eggs
Self Pollination
Plant fertilizes it own eggs

10. Pollen from one flower fertilizes the egg of another
Cross Pollination
Pollen from one flower fertilizes the egg of another

11. Mendel’s Experiment: P generation
Parent Generation
Mendel selected one pea trait to examine: Flower color

12. Pea Plant Cross Pollination
Mendel cross pollinated a purple flower with a white flower

13. What do you think Mendel found
What do you think Mendel found? What would be the result of crossing a purple flower with a white flower?

14. First Generation F1 generation: First generation
Mendel decided to let the F1 generation to self-pollinate (fertilize own eggs)
Mendel found that the resulting plants ALL had purple flowers

15. F2 generation: Second generation
Mendel found that the resulting generation had purple and white flowers; in a 3 to 1 ratio

16. Conclusions: What does all of this mean?
1. Individuals inherit “factors” from parents

17. Conclusions: What does all of this mean?
2. These “factors” are passed from one generation to the next

18. Conclusions: What does all of this mean?
3. “Factors” may be passed along, but may not show up in offspring

19. Over 100 years later … Mendel explained:
1. The “factor” is a gene; part of DNA that codes for a trait; Flower color is a gene

20. 34 years later … Mendel explained:
2. An allele is two different forms of a gene; Purple and White flowers

21. 34 years later … Mendel explained:
3. On average, there are two alleles for each trait; one from mom and one from dad

22. Dominant and Recessive Alleles
DOMINANT allele: Expressed trait; Capital letter, Always first

23. Dominant and Recessive Alleles
recessive allele: Only expressed if paired with another recessive; Lowercase letter

24. What is genotype?
Combination of alleles; allele letters that code for a trait; GENETIC makeup of gene

25. a. Homozygous Dominant: Two dominant alleles
Types of Genotypes
a. Homozygous Dominant: Two dominant alleles BB

26. b. Homozygous Recessive: Two recessive alleles
Types of Genotypes
b. Homozygous Recessive: Two recessive alleles bb

27. c. Heterozygous: One dominant and one recessive allele
Types of Genotypes
c. Heterozygous: One dominant and one recessive allele Bb

28. What is phenotype?
Physical expression of trait; observable characteristic; physical appearance

29. Example B = Big nose and b = small nose
What would be the phenotype for the following: BB Bb bb

30. Example B = Big nose and b = small nose
What would be the genotype for the following: BB Bb bb

31. Baby Lab
Heads: Dominant allele; N1, etc
Tails: Recessive allele; N2, etc