Sometimes, things don’t always follow Mendel’s Laws

1. Genetics Since Mendel Sometimes, things don’t always follow Mendel’s Laws • Write the following in your notes: I can predict an outcome of a cross using • incomplete dominance and codominance.

2. 1. Science Starter

3. 2. 3.

4. 1.

5. 2. 3.

6. Codominance In some instances, certain traits are codominant. That means that one trait cannot win out over the other form of the trait. In the offspring, both traits show up equally. Genotype RW Genotype WW Genotype RR

7. With Codominance…. BB BW WW Yo, girl. ‘Sup? RW WW RR In cows, this red & white pattern is known as roan.

8. T TT BT BT BT A cross between a tan cat (TT) and a black cat (BB) results in a third phenotype we refer to as a “Tabby.”

9. Blood also provides us with a great example of co-dominance. There are four types of blood: A, B, AB, and O. A & B are co-dominant while O is always recessive (though seldom written as a lower case letter.) If a person with homozygous B blood crosses with a person with homozygous A blood, the genotypes for the offspring will be AB.

10. AO AO AB AO AO AO AO AB AO BO BB AB OO BO BO OO Type O blood is like any other recessive trait. The only way a child can be born with type O blood is if both parents have at least one recessive O allele in their genotype.

11. The different types of blood are not necessarily interchangeable. If you give someone the wrong blood during a transfusion, it can result in serious medical problems and potentially even death. When incompatible blood is mixed it clumps together and forms clots.

12. A person with blood Type A can receive Type A blood and Type O blood. Why is Type O not a threat to the body? It does not have antigens, so it is not read as a threat. A person with blood Type B can receive Type B blood and Type O blood. Why is Type O not a threat to the body? It does not have antigens, so it is not read as a threat. A person with blood Type AB can receive Type AB blood, Type A blood, Type B blood, and Type O blood. A person with Type AB is known as a universal recipient. A person with blood Type O can only receive blood from others with blood type O. However, since any recipient can receive O blood, a person with O blood is called a universal donor.

13. CLOSING • If a child has type O blood, what must be true about the parents? • a. both parents must have genotype oo • b. at least one of the parents must have genotype oo • c. both parents must have at least one recessive o allele • d. at least one parent must have one recessive o allele • 2. If Kristina has blood AO and her husband has blood type BB, • what are the possible blood genotypes for their children? • a. BO, AB b. B, BB c. AB, AA d. all of the above • 3. Ava’s parents both have type O blood. What must • Ava’s blood type be?__________ • a. it depends on the genotypes of her parents • b. Ava’s parents must be oo, so she must also have oo. • c. Ava could have any blood type because O is the universal • blood type • d. Ava can have any blood type except O

14. 4. Which of the following is a genetic characteristic that Kaila could have • inherited from her parent? • A. scars from a bicycle accidentB. the color of her hairC. the ability to bowl wellD. his handwriting ability • 5. Shawn and Charlie are exploring a remote part of the Taklimakan Desert • when they discover a new species of beetle. Of the beetles they observed, • about 723 had long jaws and 250 had short jaws. What can we infer about • the genes for jaw shape? • The form of the gene for long jaws is recessive • The form of the gene for short jaws is co-dominant • The forms of the gene for long jaws is dominant • There is no way of telling from these observations

15. Day 2 I can predict an outcome of a cross using incomplete dominance and codominance.

16. 1. 2. Science Starter

17. 3. 4.

18. 5. In humans, the form of the gene for brown hair (B) is dominant over the form of the gene for red hair (b). If two people with brown hair have children, what can we predict about their offspring?

19. 1. 2.

20. 3. 4.

21. 5. In humans, the form of the gene for brown hair (B) is dominant over the form of the gene for red hair (b). If two people with brown hair have children, what can we predict about their offspring? Since we don’t know the exact phenotype of the parents, we cannot say for sure that the offspring will have brown hair. If both parents have genotype Bb, for example, then there is a 25% chance that an offspring will have a different hair color. The best we can say is that the offspring will most likely be born with brown hair.

22. Incomplete Dominance In other instances, two forms of a gene have incomplete dominance. That means that when the two genes compete, neither wins outright. Instead, the phenotype of the offspring present a mixture of the two traits. For example, if in a particular flower species Red and White were co-dominant, a mix of the two would result in pink flowers, white flowers with red stripes, or red flowers with white stripes. Since the colors Red and White are co-dominant or have incomplete dominance over each other, the genotype for a pink flower is NOT written as P, but as RW. A Punnett square showing what would happen if you crossed a red flower with a white flower would look like this. RW does not mean that each of the offspring has both red and white in the flowers. That would be codominance. Incomplete dominance means that a blend of the two colors shows up as the phenotype. In this case, red and white blend to make pink. The phenotype for genotype RW is pink. R R W W

23. Cross of two purple flowers____ X ____ • What are gamete possibilities? • genotype ratio 25% RR 50% RB 25% BB • phenotype ratio 25% red 50% purple 25% blue • Can you have a heterozygous red orhybrid blue flower? ___ RB RB R B RR RB R red purple BB RB B no purple blue

24. 1. Suppose the allele for black fur (B) and white fur (W) have incomplete dominance in a small rodent. What percentage of the offspring will be gray if a black rat mates with a white rat? 2. Suppose the allele for black fur (B) and white fur (W) are codominant in a small rodent. What percentage of the offspring will be white if a black rat mates with a white rat? This is a trick question….;) 100%

25. 3. A Punnett square showing what would happen if you crossed two pink flowers would look like this. R W R W How many of these offspring would be pink? 50% How many would be white? 25% How many would be red? 25%

26. 4. A tabby cat is a cross between a black • cat and a tan cat. The tabby cat’s • coloring demonstrates__________________. • That black is dominant over tan • That tan is dominant over black • That black and tan are co-dominant • That black and tan have incomplete dominance

27. 5. A cross between white snapdragons (W) and red snap dragons (R) • produces snapdragons that are pink. What would be the genotype • for the pink snapdragons? • PP b. WP c. RW d. PR • 6. This is an example of: • Incomplete dominance • Complete dominance • Co-dominance • Co-recessive traits

28. 7. Josh has a square head like Frankenstein that is caused by a • recessive form of the head-shape gene (o). Oval shaped heads • (O) are dominant. Josh doesn’t like his Frankenstein head, so • he wants to make sure that none of his children are born with • this trait. What must he do to ensure none of his children have • Frankenstein head? • Only marry and have children with a woman who is heterozygous for oval head. • Only marry and have children with a woman who is homozygous for oval head. • Marry and have children with any woman who has the oval head phenotype. • Not worry because recessive traits can only be passed down if the woman carries them • 8. Haye’sparents have blood genotypes AO and • AB. Hayes could have any blood type except: • a. A B. B c. AB d. O

29. 9. Mendel’s experiments demonstrated that any time two hybrids are cross-bred the recessive trait will appear in the phenotype of ___________% of the offspring. a. 100% b. 75% c. 50% d. 25% 10. The four blood types are _________________________ a. A, C, B, O b. A, B, O, OO c. A, B, AB, O d. A, B, C, and D 11. Which blood type(s) are dominant? a. A, O b. B, O c. A, B d. just O

30. 12. If the genes for black (B) and white (W) feathers on a particular species of • bird show incomplete dominance, what would be the genotype for gray • feathers? a. GG b. BG c. BW d. WG • 13. If a male pigeon has gray feathers and his mate has black feathers, what • phenotypes are possible in their children? (B- Black, W-White) • black, gray, or white feathers • black or white feathers • black or gray feathers • d. white or gray feathers • 14. Werewolves who are purebred for the werewolf gene (WW) can turn into • werewolves any time they want to. Werewolves who are hybrid for the • werewolf gene (Ww) can only change into werewolves on the night before, • during, and after a full moon. If a female purebred werewolf breeds with a • hybrid male and they have 12 pups, how many of the pups will be • purebred werewolves? • a. 0 b. 2 c. 3 d. 6

31. 15. Mr. Chip enjoys breeding orchids because of the enormous • challenge involved. Part of the fun is trying to cross orchids with • different colored flowers to create new hybrids. In one experiment, • he bred a maroon orchid with a gold • orchid and produced orchids with this • color and pattern which he called Royal • Benjamin. This pattern demonstrates: • a. Incomplete dominance • b. Co-dominance • Complete dominance • 16.If Mr. Chip wanted to breed and sell only Royal Benjamin hybrid • orchids, what should he do to ensure he produces the most Royal • Benjamin hybrids possible? • a. Breed Royal Benjamins with only gold orchids. • b. Breed Royal Benjamins with only maroon orchids. • c. Breed Royal Benjamins only with Royal Benjamins. • d. Breed only gold orchids with maroon orchids.

32. 17. When a farmer cross breeds a purebred white cow with a purebred red cow, this color pattern (known as roan) results: • What can we infer about the genes controlling fur color in this breed of cattle? • Red and white are co-dominant. • Red and white have incomplete dominance. • White is dominant over red since more of the cow is white than red. • Red is dominant to white since the head of the cow is mostly red. Special Note: Many cattle and horse breeders consider the roan pattern an example of incomplete dominance. I am not going to go into how or why, but if you see it listed as such, go with it.

33. 18. Bubba has type A blood. His wife, Betty-Lou, has type B blood. Their • daughter, Violula has type O blood. How is this possible? • a. Bubba has type AA and Betty Lou has type Bo. • b. Bubba has type Ao and Betty Lou has type BB • c. Bubba has type Ao and Betty-Lou has type Bo • d. There is no way for the daughter to have type O blood. • 19.Two horses that are gray-blue in color are bred. Over time, these two • horses produced foals that were black, white, and gray-blue. • What can we infer about genes that regulate fur color in this breed of • horse? • Black and white have incomplete dominance • Black is dominant over white • Black and white are co-dominant • Black is recessive to white

34. Day 3 Write in your notes: I can recognize that selective breeding can produce plants or animals with desired traits.

35. Science Starter 1. 2.

36. 3. In the alien species known as dwarks, pig-noses (P) are dominant while pointy noses (p) are recessive. If a certain dwark (Dylan) has genotype Pp, what type nose does he have? • Pointy • Pig-nose • A mix between pointy and pig-nose • A completely different nose shape

37. 4. In Gregor Mendel’s pea experiments, the purple flower color (P) was dominant over the white flower color. What genotype will result in the purple flower color? • PP b. Pp c. pp d. both PP and Pp • 5. The original vampires from Transylvania were purebred vampires (VV) meaning they were born vampires. A human bitten by a purebred vampire turns into a vampire-human hybrid (Vv). If two of these vampire hybrids(Cayleigh& Jake) breed, what percentage of their offspring will be born purebred vampires? • a. 0% b. 25% c. 75% d. 100%

38. 1. 2.

39. 3. In the alien species known as dwarks, pig-noses (P) are dominant while pointy noses (p) are recessive. If a certain dwark(Reginald) has genotype Pp, what type nose does he have? • Pointy • Pig-nose • A mix between pointy and pig-nose • A completely different nose shape

40. 4. In Gregor Mendel’s pea experiments, the purple flower color (P) was dominant over the white flower color. What genotype will result in the purple flower color? • PP b. Pp c. pp d. both PP and Pp • 5. The original vampires from Transylvania were purebred vampires (VV) meaning they were born vampires. A human bitten by a purebred vampire turns into a vampire-human hybrid (Vv). If two of these vampire hybrids(Cayleigh& Jake) breed, what percentage of their offspring will be born purebred vampires? • a. 0% b. 25% c. 75% d. 100%

41. Selective Breeding Suppose a farmer has two types of corn. One type has small ears but big kernels. The other type has big ears but tiny kernels. The farmer may plant the two types of corn next to each other so that the pollen from each type of corn can fertilize the other type. What the farmer hopes is that some of the corn plants will develop ears of corn that are both big and that have big kernels too. This type of genetic cross pollination is known as selective breeding. Selective breeding is the process where humans try to isolate certain favorable traits in plants and animals by crossbreeding animals and plants of the same species but ones that have different forms of certain genes. Selective breeding has been done for thousands of years with both plants and animals. All domesticated cattle, horses, dogs, and cats are products of selective breeding. That is why there are so many “breeds” of these animals. Humans cross bred these animals in an attempt to isolate desired traits. Dogs such as Dachshunds and Bassett Hounds are a result of hunters trying to breed the “short leg” version of the gene for leg length into another breed of dog so that they could have a hunting dog that was short enough to chase rabbits through the maze of rabbit trails in a thicket of woods.

42. SELECTIVELY-BRED DESIGNER FRUITS USDA created Carrots PINEBERRY PLUOT GOLDEN WATERMELON

43. Double Muscling- Good Science or Animal Cruelty (STOP video at 3:30.) http://www.youtube.com/watch?v=rW54_vM9SF0

44. Mr. Moore grew two types of tomatoes in his back yard. One produced lots of small, sweet tomatoes. The other didn’t grow as many tomatoes but the ones that did grow were much larger. What might Mr. Moore hope to accomplish by cross-breeding these two types of tomatoes? By crossing these two tomato plants, he may eventually create a new hybrid tomato plant that produces lots of large, sweet tomatoes. 2. What process did Mr. Moore use to create his hybrid in question #1? Selective breeding. 3. Donovan is a rose grower. He grows mostly red roses, but occasionally some of his roses turn out pure white due to a recessive form of the flower color gene. Lots of people in his area produce red roses (and the few white roses that grow from time to time), but none of them grow only white roses. Donovan decides he can do better if he only produces white roses since there is less competition. What would he need to do in order to ensure his plants produced only white roses? Only breed white roses with other white roses. 4. Which of the following genetic traits might cattle farmers be interested in selectively breeding into their cattle? a. larger size (more meat per animal) b. less resistance to certain parasitic diseases c. larger ears to keep them cooler in summer d. muscle structure that allow them to run faster

45. 5. In the sport of horse racing, race horse owners may pay $1,000,000 for the right to allow one of their horses to breed with a champion race horse. Their hope is that some of the genes that helped the champion become so successful will be passed on to the offspring. This is an example of _________________________ 6. The tiny Chihuahua and the Great Dane are both dogs. What is the best explanation for why these two breeds of dog differ so greatly? selective breeding. First of all, Chihuahuas aren’t dogs-they are rats that bark. Now that we have that out of the way, the answer is both dogs have been selectively bred by humans for specific physical traits.

46. 7. In Nepal, male Yaks are bred with female domestic cows to create a hybrid • animal that has good tasting meat and that can survive the high altitudes and • cold temperatures of Nepal. This is an example of ____________________. selective breeding

47. Day 4 Write in your notes: I can explain how genetic modification differs from selective breeding.

48. 1. Science Starter

49. 2. Unattached or “free” earlobes (E) are dominant. Attached • earlobes (e) are recessive. Justin is heterozygous • for unattached earlobes. Medeline has attached earlobes. • What is the probability that a child of theirs will have • attached earlobes? • 0 % b. 50% c. 75% d. 100% • 3. Kinsey and Caleb both have free earlobes. What • prediction can we make about children they may have? • The children will most likely have free earlobes • The children will definitely have free earlobes • The children will most likely have attached earlobes • The children will definitely have attached earlobes

50. 1.