Simple Genetics Quiz

Transcription

1 Simple Genetics Quiz Matching: Match the terms below to their correct definition. (1 point each) 1. heterozygous 2. homozygous 3. dominant 4. recessive 5. phenotype 6. Cystic Fibrosis 7. Sickle Cell Anemia 8. PKU 9. Huntington s Disease 10. Allele Multiple Choice: Choose the best answer. (2 points each) a. A recessive disease characterized by mucus in the lungs b. The inheritable, genetic information of a person c. A person with both a dominant (A) and recessive (a) allele d. A recessive disease in which a person is missing an enzyme to break down certain amino acids e. A person with two identical alleles (AA or aa) f. A recessive disease characterized by misshapen red blood cells g. A dominant disease characterized by decline in muscle function h. The weaker allele that will only show up if no other alleles are present i. The stronger allele that will display the trait whenever it is present j. The outward, physical appearance of a person k. A variant form of a gene 1. The diagram below represents a Punnett square. What are the genotypes for offspring of these parents BB x bb? a. BB, BB, bb, bb b. BB, Bb, Bb, bb c. BB, Bb, bb, bb d. Bb, Bb, Bb, Bb 2. In guinea pigs, black coat color (B) is dominant to white coat color (b). What percentage of the offspring will be white when a homozygous black guinea pig is crossed with a homozygous white guinea pig? a. 0% b. 25% c. 50% d. 100% 3. A man and his wife both have widow s peaks. Their baby has a continuous hairline. Which best explains how this could happen? a. Both parents have heterozygous genotypes. b. Both parents have homozygous dominant genotypes. c. One parent is homozygous dominant, and the other is heterozygous. d. One parent is homozygous dominant, and the other is homozygous recessive.

2 4. A man has a recessive genetic condition that neither of his parents expressed. His wife does not have this condition. However, she is a carrier. Based on this information, which Punnet square correctly predicts the probability that their children will have this genetic condition? 5. Suzette owns a litter of rabbits. There are three black rabbits and one white rabbit. Black coat color (B) is dominant to white coat color (b). What most likely are the genotypes of the parents? a. BB, BB b. BB, Bb c. Bb, Bb d. Bb, bb 6. Tongue rolling (T) is dominant to nontongue rolling (t) in humans. What phenotypic ratio is possible for offspring produced between a nontongue roller (tt) and a heterozygous (Tt) tongue roller? a. all tongue rollers b. all nontongue rollers c. 1 to 1 ratio of tongue rollers to nontongue rollers d. 3 to 1 ratio of tongue rollers to nontongue rollers

3 7. In humans, free earlobes are dominant to attached earlobes. If a homozygous dominant male has children with a homozygous recessive female, what percent of their children can be expected to have free earlobes? a. 0% b. 25% c. 50% d. 100% 8. When crossing parents with genotypes Rr and rr, what will be the percentages of the genotypes of the offspring? a. 75% Rr, 25% rr b. 50% Rr, 50% rr c. 100% Rr d. 100% rr 9. Tall plants are dominant to short plants. What is the outcome if two short plants are crossed? a. all tall plants b. all short plants c. half tall plants, half short plants d. ¼ tall plants, ¾ short plants 10. What information can be revealed by a Punnett square? a. pattern of inheritance in families b. genotype and phenotype of an individual offspring c. potential genotypes and phenotypes of offspring d. potential chromosomal abnormalities in offspring 11. Which is a heterozygous genotype? a. B b. B c. BB d. Bb 12. How can two organisms have the same phenotype but different genotypes? a. One organism is heterozygous, and the other organism is hybrid. b. One organism is heterozygous, and the other organism is homozygous recessive. c. One organism is homozygous dominant, and the other organism is homozygous recessive. d. One organism is homozygous dominant, and the other organism is heterozygous.

4 13. Sickle cell anemia is a genetic disease caused by an autosomal recessive gene. If each parent carries one sickle cell allele, what are the chances that their child will have sickle cell anemia? a. no chance b. one in four c. two in four d. three in four 14. Phenylketonuria (PKU) is inherited as a recessive condition. A man with PKU marries a woman without any alleles for PKU. What is the probability that their child will inherit PKU? a. 100% b. 75% c. 50% d. 0% 15. Which is an example of the environment influencing the expression of a genetic trait? a. hemophilia in Queen Victoria s family b. widow s peak in each generation of a family c. great variation in height seen in members of a family d. formation of freckles after sun exposure in members of a family 16. For the following genotypes, indicate whether the genotype is homozygous dominant, homozygous recessive or heterozygous: (2 pts each, 6 points total) A) Aa B) aa C) AA 17. For the following genetic diseases, indicate whether it is controlled by a dominant or recessive trait: (2 points each, 8 points total) A) Cystic Fibrosis B) Huntington s C) Sickle Cell D) PKU

5 18. For the following description, select the disease to match (1 point each, 7 points total) 1. Can t eat a lot of protein A. cystic fibrosis 2. Missing the enzyme to break down an amino acid B. PKU 3. Results from an immunity to malaria C. sickle-cell anemia 4. Phenylketonuria D. Huntington s 5. Dominant disease 6. Causes mental loss 7. Onset late in life 19. For each of the following, indicate whether it describes a genotype or a phenotype: (1 point each, 3 points total). 1. Aa 2. Blue eyes 3. Homozygous dominant 20. Having freckles is recessive (f) to not having freckles (F). Fill in the following Punnett squares. (6 points each, 12 points total) F f F f f F f F How many boxes above say FF? What percent of offspring will have the genotype FF? % How many boxes above will say FF? What percent of offspring will have the genotype FF? % 21. Kia s friend, Julie, also wants to know if babies she has with Mark will be able to roll their tongues. Julie is homozygous dominant and Mark is can t roll his tongue. What percent of their children WILL be able to roll their tongues? Complete a Punnett Square to justify your answer. (6 points)

6 22. A homozygous dominant male marries a carrier female for PKU. Complete the Punnett square. What percent of the offspring will have PKU? (6 points) 23. A male with Huntington s disease (whose mother did not have Huntington s Disease) marries a woman without Huntington s disease. What percent of the offspring will have Huntington s? Complete the Punnett Square to justify your answer. (6 points) 24. People with PKU have to be careful of what they eat and avoid foods high in phenylalanine, such as meat and dairy. If they did not do this, what might happen? (3 points) 25. How can it be considered advantageous to be a carrier for the Sickle Cell trait? (3 points)