Bell Ringer

1. Bell Ringer • What does NOT happen between Meiosis I and Meiosis II that reduces the number of chromosomes? • When animals reproduce, which process replicates their chromosomes? • In one sentence, describe what happens during Meiosis I.

2. Mendelian Genetics and Punnett Squares • Biology • February 13, 2014

3. Gregor Mendel • Austrian monk who studied garden peas. • Noticed certain patterns as he observed each generation. • Began experimenting by crossbreeding. • crossbreeding: mating two organisms to produce offspring

4. Mendel’s Traits • Mendel studied seven different traits: • height (tall/short) • flower color (purple/white) • flower position (axial/terminal) • seed color (yellow/green) • seed shape (round/wrinkled) • pod color (green/yellow) • pod shape (inflated/constricted)

5. HUMAN TRAIT INVENTORY

6. Describe the two pea plants. B A : Dwarf Height: Flower Color: Flower Position: Height: Flower Color: Flower Position: : Tall : White : Purple : Axial : Terminal

7. Gregor Mendel’s Experiments • 1) chose a trait to examine • 2) cross-pollinated members of the parent (P) generation • 3) counted the results in the first filial (F1) generation • 4) cross-pollinated members of the F1 generation • 5) counted the results in the second filial (F2) generation

8. Mendel’s Experiments • P Generation: Purebred Tall x Purebred Short • Result (F1 Generation): All Tall • F1 Generation: Tall x Tall • Result: (F2 Generation) 75% Tall, 25% Short

9. Gregor Mendel’s Conclusions **** • traits are inherited from one’s parents. • traits follow specific laws as they are passed, resulting in predictable ratios • ex. heterozygous tall x heterozygous tall T t 75% Tall 25% Short TT Tt T Tt tt t

10. Genetics Vocabulary : a piece of DNA that codes for a trait • gene: • ex. height

11. Genetics Vocabulary : different forms of the same gene • allele: • each individual has two alleles for each trait • one allele comes from each parent • ex. T or t • dominant allele: • recessive allele: : always expressed when present : expressed when no dominant is present

12. Genetics Vocabulary : combination of alleles for a trait • genotype: • homozygous: • ex. TT or tt • heterozygous: • ex. Tt • phenotype: • ex. tall or short : both alleles are the same : both alleles are different : physical characteristic of an organism

13. Genotype vs Phenotype Trait: pea plant height

14. Review Directions: Identify the following as a trait/gene, an allele, a genotype, or a phenotype. • Y • Ww • Flower Color • Yellow Seeds • TT • Flower Position • t • Dwarf • Plant Height • Purple Flowers allele trait/gene genotype allele trait/gene phenotype phenotype trait/gene genotype phenotype

15. PRACTICE!

16. Mendel’s Laws • 1. The Law of Segregation: • the two alleles that make up the genotype separate during meiosis so that each gamete only has one copy T \ T TT \ T \ t Tt \

17. Mendel’s Laws • 2. The Law of independent assortment: • alleles of different genes assort independently TW \ TtWw Tw \ tW \ tw \

18. Mendel’s Laws • 3. The Law of Dominance: • if a dominant allele is present in the genotype, it will be expressed in the phenotype Tall (TT) Tall (Tt) Dwarf (tt)

19. What type of car is this? GAS + ELECTRIC Hybrid = MIXED FROM 2 PARTS

20. Mom + Dad 1 Pair of Traits Monohybrid Cross ONE MIXED MATING

21. Punnett Square: • a diagram used to predict the outcome of a particular genetic cross t T Father’s Genotype T Mother’s Genotype T Possible Offspring inside boxes

22. Multiplication Table

23. Multiplication Table

24. Punnett Square: • a diagram used to predict the outcome of a particular genetic cross t T Father’s Genotype T Mother’s Genotype T Possible Offspring inside boxes

25. tall (T) is dominant to short (t) Genotype 50% Tt 50% tt 1:1 Phenotype 50% tall 50% short 1:1 T t heterozygous tall t Tt tt hetero tall homo short homozygous short t tt Tt hetero tall homo short

26. tall (T) is dominant to short (t) Genotype 25% TT 50% Tt 25% tt 1:2:1 Phenotype 75% tall 25% short 3:1 T t heterozygous tall T TT Tt homo tall hetero tall heterozygous tall NOTE: All monohybrid Crosses of heterozygous of parents produce these ratios. t tt Tt hetero tall homo short

27. purple flowers (W) are dominant to white (w) Genotype 100% Ww Phenotype 100% purple W W homozygous purple w Ww Ww hetero pur hetero pur homozygous white w Ww Ww hetero pur hetero pur

28. purple flowers (W) are dominant to white (w) Genotype 50% Ww 50% ww 1:1 Phenotype 50% purple 50% white 1:1 W w heterozygous purple w Ww ww hetero pur homo white homozygous white w ww Ww hetero pur homo white

29. Review • What are genes? • What’s a genome? • How many copies of each gene do we each inherit? • What is probability? • Organisms that have two identical alleles for a particular trait or what? • What do letters inside a Punnett square represent? • If a tree is homozygous recessive for height (T, t), how would its alleles be represented? • When Mendel crossed a tall plant with a short plant, the F1 plants inherited what?

30. Review • Which principle states that during gamete formation, genes for different traits separate without influencing each other’s inheritance? • If you flip a coin 67 times, what’s the probability that it will come up heads? • If two people that cross their eyes (E) marry and have a child that cannot cross their eyes (e), what are the genotypes of the parents? Why? • Who or what does Gregor Mendel’s principles of genetics apply to?

31. Independent Practice • Complete Monohybrid Cross worksheet (Will be checked during Bell Ringer tomorrow. NO LATE WORK ACCEPTED) • Review Vocabulary (All words are on Quizlet) Remember, Ch. 6-3,4,5,6 Vocabulary Quiz Tomorrow!