Hths 2231 Laboratory 3 Genetics

Transcription

1 Watch Movie: Cystic Fibrosis Answer the movie questions on the worksheet. Complete activities 1-5 Activity #1: Under Lab 3 Click on activity 1 Click on Tour of the Basics Do all 6 What is exercises Activity #2: Click on activity 2 Build your own DNA molecule and transcribe and translate a gene. Activity #3: Click on activity 3 Click on What are Genetic Disorders o Review levels 1-3, and cite diseases associated with each. Click on and review Newborn Genetic Screening. Read about the 4 types of genetic disorders. Activity #4: Click on activity 4 List 3 different patterns of inheritance. In each case discuss the percentage of children that will be normal, carriers, and affected. Activity #5: Complete the case studies on your worksheet using your text when needed.

2 1. Approximately how many genetic diseases exist? 2. Hereditary characteristics are transmitted through? 3. The cystic fibrosis gene is : a. dominant b. recessive c. sex-linked dominant d. sex-linked recessive 4. An individual that inherits a normal gene from one parent and a cystic fibrosis gene from the other parent is called a. 5. The term carrier can be defined as: 6. How does an individual acquire the disease, cystic fibrosis? 7. If both parents carry a recessive gene for cystic fibrosis, their children will have a % chance of inheriting the disease and a % chance of being a carrier. 8. What is the incidence of cystic fibrosis in Caucasians? 9. What is the incidence of cystic fibrosis carriers in North America? 10. The transport of what ion is affected in cystic fibrosis? 11. The defective transport of this ion causes a layer of to form. 12. Which two systems are primarily affected by cystic fibrosis? 13. In the gastrointestinal tract, cystic fibrosis causes difficulty in absorbing,, and. 14. In the respiratory tract, what 3 functions are affected by the thick mucous secreted in patients with cystic fibrosis? 15. List 5 complications of cystic fibrosis that will eventually lead to death. 16. How is cystic fibrosis diagnosed? 17. What is the prognosis for a patient with cystic fibrosis? 18. How is cystic fibrosis treated? 19. Research for cystic fibrosis is concentrating on what 3 areas?

3 1. Mrs. Smith s teenage daughter is short in stature, has relatively little body hair, underdeveloped breast with nipples far apart, and webbing in the neck. Chromosomal mapping shows simple monosomy of the X chromosome. Your diagnosis is: 2. Mr. Jones 15 year-old son has developed female-like breasts, has small testes, and his voice is still quite high-pitched. Chromosomal mapping shows a 47XXY karyotype. This syndrome is: 3. A 6 month-old child, born at an abnormally low birth rate, has an abnormally small head, heart defects, learning disabilities and a shrieking cry. a. What is your diagnosis? b. This is an example of what type of chromosome abnormality? 4. Alyssa Turner, 5 year-old, is short in stature with severe learning impairments. Her face is characteristic of her genetic abnormality. She had low nasal bridge, eyelids that are folded, a protruding tongue and flat, low set ears. She had already had surgery for a congenital heart defect. a. What disease do you suspect? b. What chromosomal pattern would you expect to find? 5. Mr. and Mrs. James have 4 children, two boys and two girls. One of the boys and one of the girls inherited a disease from Mr. James. The other 2 children are not affected. Mr. James mother was also afflicted with the disease. a. The most likely inheritance pattern in this case is b. Draw a Punnett square expressing this inheritance pattern.

4 6. Bill married his second cousin Betty. Both have normal health histories. Bill and Betty had 7 children. One daughter and one son have cystic fibrosis. a. This is an example of what type of inheritance pattern? b. Draw a Punnett square expressing this inheritance pattern. 7. Refer to the pedigree chart on the next page for the following questions. In this pedigree chart of a family with known hemophilia, circles represent females, squares represent males, dotted circle represent carriers, and solid colored squares represent males with hemophilia. a. This hemophilia pedigree chart is indicative of what type of pattern? b. Check is the appropriate statement(s) that can be determined from this chart? 1. Hemophilia male #14 could have a son with hemophilia. 2. Hemophilia male #1 could have daughters that are carriers of the hemophilia gene. 3. Daughter #9 could have a son with hemophilia. 4. Daughter #4 could have a daughter with the hemophilia gene. 5. Hemophilia male #1 could pass the hemophilia gene to his sons. c. Why does the expression of hemophilia gene skip generations?

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6 ANSWERS TO CYSTIC FIBROSIS WORKSHEET 1. Approximately how many genetic diseases exist? APPROX Hereditary characteristics are transmitted through? DNA/GENES 3. The cystic fibrosis gene is : a. dominant b. recessive c. sex-linked dominant d. sex-linked recessive ANS: B RECESSIVE 4. An individual that inherits a normal gene from one parent and a cystic fibrosis gene from the other parent is called a. CARRIER 5. The term carrier can be defined as: INDIVIDUAL WILL NOT DEMONSTRATE THE DISEASE BUT CAN PASS THE GENE TO THEIR CHILDREN. 6. How does an individual acquire the disease, cystic fibrosis? AN INDIVIDUAL WITH CYSTIC FIBROSIS HAS INHERITED A RECESSIVE CYSTIC FIBROSIS GENE FROM BOTH PARENTS. 7. If both parents carry a recessive gene for cystic fibrosis, their children will have a % chance of inheriting the disease and a % chance of being a carrier. 25%, 50% 8. What is the incidence of cystic fibrosis in Caucasians? 1 IN 2000 HAVE THE DISEASE 9. What is the incidence of cystic fibrosis carriers in North America? 1 IN 20 ARE CARRIERS 10. The transport of what ion is affected in cystic fibrosis? Cl The defective transport of this ion causes a layer of to not form. WATER 12. Which two systems are primarily affected by cystic fibrosis? GASTROINTESTINAL, RESPIRATORY 13. In the gastrointestinal tract, cystic fibrosis causes difficulty in absorbing,, and. PROTEINS, FATTY ACIDS, VITAMINS 14. In the respiratory tract, what 3 functions are affected by the thick mucous secreted in patients with cystic fibrosis? BREEDING GROUND FOR INFECTIONS, MECHANICAL OBSTACLE TO AIR CIRCULATION, GAS EXCHANGE IN THE ALVEOLI 15. List 5 complications of cystic fibrosis that will eventually lead to death. EMPHYSEMA, CHRONIC BRONCHITIS, ANATOMICAL DESTRUCTION, RESPIRATORY INSUFFICIENCY, AND HEART FAILURE 16. How is cystic fibrosis diagnosed? SWEAT TEST 17. What is the prognosis for a patient with cystic fibrosis? FATAL; AVERAGE LIFE EXPECTANCY IS 29 YEARS

7 18. How is cystic fibrosis treated? DRUGS, PHYSIOTHERAPY 19. Research for cystic fibrosis is concentrating on what 3 areas? CURE, TREATMENT, PHARMACOLOGY ANSWERS TO GENETICS WORKSHEET 1. Mrs. Smith s teenage daughter is short in stature, has relatively little body hair, underdeveloped breast with nipples far apart, and webbing in the neck. Chromosomal mapping shows simple monosomy of the X chromosome. Your diagnosis is: TURNER SYNDROME 2. Mr. Jones 15-year-old son has developed female-like breasts, has small testes, and his voice is still quite high pitched. Chromosomal mapping shows a 47XXY karyotype. This syndrome is: KLIENFELTER SYNDROME 3. A 6 month-old child, born at an abnormally low birth rate, has an abnormally small head, heart defects, severely developed learning abilities, and a shrieking cry. a. What is your diagnosis? CRI DU CHAT SYNDROME b. This is an example of what type of chromosome abnormality? DELETION 4. Alyssa Turner, 5 year-old, is short in stature with severe learning impairments. Her face is characteristic of her genetic abnormality. She has low nasal bridge, eyelids that are folded, a protruding tongue and flat, low set ears. She has already had surgery for congenital heart defect. a. What disease do you suspect? DOWN S SYNDROME b. What chromosomal pattern would you expect to find? TRISOMY OF THE 21 ST CHROMOSOME

8 5. Mr. and Mrs. James have 4 children, two boys and two girls. One of the boys and one of the girls inherited a disease from Mr. James. The other 2 children are not affected. Mr. James mother was also afflicted with the disease. a. The most likely inheritance pattern in this case is AUTOSOMAL DOMINANT b. Draw a Punnett square expressing this inheritance pattern. d d D Dd Dd d dd dd 6. Bill married his second cousin Betty. Both have normal health histories. Bill and Betty had 7 children. One daughter and one son have cystic fibrosis. a. This is an example of what type of inheritance pattern? AUTOSOMAL RECESSIVE b. Draw a Punnett square expressing this inheritance pattern. D d D DD Dd d Dd dd 7. Refer to the pedigree chart on the next page for the following questions. In this pedigree chart of a family with known hemophilia, circles represent females, squares represent males, and solid colored squares represent males with hemophilia. a. this hemophilia pedigree chart is indicative of what type of pattern? X-LINKED RECESSIVE b. Check the appropriate statement(s) that can be determined from this chart? NO 1. Hemophilia male #14 could have a son with hemophilia. YES 2. Hemophilia male #1 could have daughters that are carriers

9 of the hemophilia gene. YES 3. Daughter #9 could have a son with hemophilia. YES 4. Daughter #4 could have a daughter with the hemophilia gene. NO 5. Hemophilia male #1 could pass the hemophilia gene to his sons. c. Why does the expression of Hemophilia gene skip generations? THE GENE IS CARRIED ON THE X CHROMOSOME. A MALE WITH HEMOPHILIA WOULD PASS THE X CHROMOSOME WITH THE HEMOPHILIA GENE TO HIS DAUGHTERS WHO WOULD BE CARRIERS. HIS SONS WOULD RECEIVE THE Y GENE AND WOULD NOT BE AFFECTED. HIS DAUGHTERS COULD PASS THE HEMOPHILIA X GENE ON. THEIR SONS (50% CHANCE) WOULD EXPRESS THE DISEASE. DAUGHTERS WHO INHERIT THE AFFECTED S GENE (50% CHANCE) WOULD BE CARRIERS.