1. Catalyst 1. What are chromosomes composed of? 2. What are genes? 3. What forms the “rungs” of the DNA ladder? 4. Why is the sequence of bases important? 5. How are nitrogen base of DNA like the letters of the alphabet?

2. Catalyst 1. Why is the order of base pairs important? Be specific-- (What exactly happens if the order is wrong—be sure to mention proteins, and the genetic code).

3. I CAN… I CAN describe why the order of base pairs is important.

4. Mutation A mutation is any change in a gene or chromosome.

5. Mutations Mutations can cause a cell to produce an incorrect protein. As a result, the organism’s trait, or phenotype, may be different from what it would have normally been. Think of Hayden’s case…what happened when that protein was built incorrectly?

6. Inheriting Mutations

7. Types of Mutations Mutations can occur both at the DNA base level and at the chromosome level.

8. Effects of Mutations A mutation is harmful to an organism if it reduces an organism’s chance for survival. Reflect: When might a mutation be helpful?

9. Genetic Disorder A genetic disorder is an abnormal condition that a person inherits through genes or chromosomes.

10. Common Genetic Disorders Cystic Fibrosis Sickle-Cell Disease Hemophilia Down Syndrome

11. Exit Quiz Why is the order of base pairs important? Be specific (What exactly happens if the order is wrong—be sure to mention proteins, and the genetic code).

12. Catalyst 1. Why is the order of base pairs important? Be specific-- (What exactly happens if the order is wrong—be sure to mention proteins, and the genetic code).

13. Quick Write 1. Look around the room at the posted pictures. How many different skin colors do you see? 2. What do you believe is happening at a genetic level to produce the variety of skin color we see in the human species? Use your new understanding of genes and alleles to make an educated guess.

14. Patterns of Human Inheritance The inheritance of traits is rarely as simple as in Mendel’s experiments. Human traits rarely come in just two simple forms like pea plant flowers.

15. 3 Patterns of Human Inheritance 1. Trait controlled by single gene with 2 alleles. 2. Trait controlled by single gene with multiple alleles. 3. Trait controlled by many genes that act together.

16. Single Gene with 2 Alleles Traits that are controlled by a single gene with just two alleles only have two possible phenotypes or physical appearances. Examples: Widow’s Peak or No Widow’s Peak

17. Single Gene with Multiple Alleles Multiple alleles: three or more forms of a gene that code for a single trait. Example: A gene that comes in three forms: purple, white, and blue.

18. Single Gene with Multiple Alleles Even though a gene may have multiple alleles, a person can ONLY carry 2 of those alleles because chromosomes exist in PAIRS (not triples, quadruples etc.) Each chromosome in a pair only carries one allele for the trait. Example: Human Blood Type –A, B, AB, or O.

19. Traits Controlled By Many Genes Some human traits show a large variety of phenotypes because the traits are controlled by many genes. The genes act together as a group to produce a single trait. Example: Height, skin

20. Q: Why do some traits show so much variation? Gummy Bear Breeding Part 2

21. Gummy Bear Notes Reading

22. Introduction to GB Breeding… In gummy bears, fur color is actually controlled by TWO genes, each one with two possible alleles. For example, bears who have a genotype of CC AA for fur color will have a phenotype of green fur color. The next table reveals the remaining possible combinations of fur color alleles and the revealed phenotype (the fur color we see!)

23. Introduction continued… Copy the table below into your notes…

24. Question 1 1. What type of inheritance pattern do these gummy bears show? Multiple genes with only 2 alleles each.

25. Your task… Your job in this activity, is to predict (before looking in the brown paper bag) all of the possible genotypes and phenotypes of the baby gummy bears produced in a cross between two parent gummy bears.

26. Question 2 and 3 The genotypes of the proud gummy bear parents are labeled on the outside of your bag. 2. What are the genotypes of your expecting gummy bear parents? A.Mother Genotype: _____ _____ B.Father Genotype: _____ _____ 3. What are the phenotypes of each parent? A.Mother Phenotype: _____ _____ B.Father Phenotype: _____ _____ XX AA YY AA

27. Question 4 4. Remember that meiosis creates egg and sperm cells (the sex cells), and that each sex cell has only one allele from each parent for each gene. Given this information, list the possible alleles for each sperm or egg cell. A.Egg Options: B.Sperm Options:

28. Question 5 and 6 5. What are all of the possible genotypes for the next gummy bear generation. (Hint: mix the sex cells you created above around to find all possible combinations) 6. What will be the phenotypes for the combinations above in Question 5? Use your chart.

29. Question 7 Open the brown paper bag with the next gummy bear generation in it. Were your predictions correct? What are the phenotypes you see inside?

30. Question 8 8. Were the offsprings’ phenotypes the same or different from the parents’? Were you surprised by the results: why or why not?

31. Question 9 In gummy bears there were only two genes that determined fur color. In humans, there are over 100 genes that contribute to skin color. Explain how this will result in the HUGE variation we see in human skin color.

32. Exit Quiz What are two types of mutations? What are the three patterns of inheritance in humans?