Earth Science - Other Patterns of Inheritance

Worksheet 11.3: Other Patterns of Inheritance 1. Complete the graphic organizer to summarize exceptions to Mendel's principle. ! Mendel’s experiments cannot predict the outcome of traits that involve Incomplete dominance Example: Multiple alleles Example: Speckled chicken feathers from solid-color-feather parents Example: Example: Variety of skin color in humans For Questions 2–8, write True if the statement is true. If the statement is false, change the underlined word to make the statement true. ! 2.!When offspring show a blend of the parents’ traits, one allele is dominant over the other. ! 3.!In complete dominance, the heterozygous phenotype lies somewhere between the two homozygous phenotypes. ! 4.!A heterozygous individual that exhibits the traits of both parents is an example of codominance. ! 5.!Many genes exist in several forms and are said to have codominant alleles. ! 6.!While multiple alleles may exist in a population, an individual usually carries only two alleles for each gene. ! ! 7.!Traits produced by two or more genes are codominant. 8.!Polygenic traits often show a wide range of phenotypes. 1 9. A plant breeder produced a purple flower by crossing a red parent with a blue parent. Use RR as the genotype for the red parent and BB for the blue parent. Complete the Punnett square to show the resulting genotypes and phenotypes of the offspring. Gamete allele: Gamete allele: Gamete allele: Genotype: Genotype: Gamete allele: Phenotype: Genotype: Phenotype: Genotype: Phenotype: Phenotype: For Questions 10–11, refer to the Punnett square above. 10. What type of inheritance is the example in Question 9? ! 11. If the offspring had been red and blue spotted flowers, what kind of inheritance would be most likely? ! 12. Explain the difference between multiple alleles and polygenic traits. ! ! ! ! For Questions 13–16, complete each statement by writing in the correct word or words. 13. An organism’s! 14. Some! conditions. results from its genotype and its environment. produce variable traits depending on environmental 15. Western white butterflies vary in their wing color because their! varies depending on when they hatch. 16. ____________________ is an environmental variable that affects wing color in western white butterflies. 2 For each of the following examples, write G if the trait is determined by genotype, and E if it is determined by environment. 17. ________ Turtles whose eggs hatch at higher temperatures tend to be female. 18. ________ A blue-eyed girl is born to blue-eyed parents. 19. ________ Bees in a colony are assigned different jobs. As they develop, workers begin to look dramatically different. 20. ________ A pair of twins is separated at birth. They grow up in different countries and speak different languages. 21. ________ A litter of puppies is born. They are all gray except for one, which is brown. 22. ________ Tall pea plant seeds are planted in different places around a yard. They produce plants of different heights. 23. ________ A kitten is born with six toes. 24. ________ A rabbit is born weak with hunger. 25. A dog gave birth to four puppies. The father has brown eyes, and the mother has green eyes. Two puppies have brown eyes, one has green eyes, and one has blue eyes. What does this information tell you about how eyed color in dogs is inherited? Explain you answer. ! ________________________________________________________________ ! ________________________________________________________________ ! ________________________________________________________________ 3 26. Use the colors pink, white, and red to demonstrate incomplete dominance in the flowers of this genetic cross. RR R WW R RW RW RW RW W W Answer the questions. 27. A the gene for a rabbit’s coat color has four different alleles. Which of the following statements is true? Circle the letter of the statement that is true. A. In a population of rabbits, there can be two different coat colors. B. In a population of rabbits, there can be four different coat colors. C. One rabbit can have fur with four different colors. D. Fur color in rabbits is a controlled by several different genes. 28. Eye color in humans is an example of a polygenic trait. Which of the following statements is true? Circle the letter of the statement that is true. A. A person always has the exactly the same eye color as one of his or her parents. B. There are only three different eye colors in humans. C. Eye color in a human population can occur in a wide range of shades. D. Eye color in humans is controlled by one gene with several different alleles. 29. Explain the difference between incomplete dominance and codominance. ! ! ! 4 5. Circle the traits that are controlled by multiple alleles. blood type in humans! tongue-rolling in humans height in pea plants! dimples in humans coat color in rabbits! skin color in humans CHAPTER MYSTERY Green Parakeets Offspring do not always look just like their parents. In the box below, draw Susan’s two parakeets and their three offspring. Color each parakeet. 5