Biology Unit 3: Genetics

1. Biology Unit 3: Genetics

2. 1. Complete the following chart comparing meiosis and mitosis.

3. 2. After observing the karyotype below, identify the genetic disorder. (Ex: 47, XY + 13 would mean that this male has an extra chromosome #13, or Trisomy 13). 45, XO, or Monosomy X

4. 3. Which of the following could NOT be determined by a karyotype? • A patient has a cytosine where a guanine should be in one segment of DNA on chromosome 12. • The patient has an extra X chromosome and has been diagnosed with Klinefelter’s Syndrome. • A fetus will be a boy. • A person had chicken pox when they were 6 years old. • Karyotypes cannot show specific sequences of DNA. • d. Karyotypes cannot show medical histories.

5. 4.For each phenotype, give the genotypes that are possible. Green peas (G) is dominant to yellow peas (g) a. Green  _________________ b. Yellow  _________________ Purple flower color (P) is dominant to orange (p) c. Purple  _________________ d. Orange  ________________ Gg, GG gg Pp, PP pp

6. 5.For each genotype, give the phenotypes that are possible. Blond hair (B) is dominant to red hair (b) a. BB or Bb  _________________ b. bb  ___________________ Dimples (D) is dominant to no dimples (d) c. DD or Dd  ___________________ d. dd  ________________ Blond Red Dimples No dimples

7. 6.What are the genotypes of all the individuals mentioned? The presence of a space between your upper teeth is called diastema. This is a dominant trait. Not having the space is a recessive trait. Mr. and Mrs. Patch had diastema corrected with braces. Briar, their son, does not have this trait. Mr. Stone does not have diastema, but Mrs. Stone does show the trait. Their daughter, Millie, does not show the trait. Briar and Millie marry and have Daisy, who does not have the trait. Mr. Patch ________ Mrs. Patch __________ Briar _____________ Mr. Stone ___________ Mrs. Stone _______ Millie _______________ Daisy ____________ Dd Dd dd dd Dd dd dd

8. 7. In petunia flowers, red flowers (R) and orange flowers (O) are codominant. A cross between a red and an orange flower produces purple flowers (RO). What would be the F1 genotypes and phenotypes of a cross between a red flower and a purple flower? RR x RO R O R R F1 Gen: 1 RR to 1 RO F1 Phen: 1 Red to 1 Purple

9. 8. Complete the following pedigree if XH = Normal and Xh = hemophiliac. You only have to do the numbered individuals! 2 1 3 5 4 6 8 7 • XHY, Normal Male 2. XHXh , Carrier Female • XhXh, Hemophiliac Female 4. XHX_, Normal Female • XhY, Hemophiliac Male 6. XHXh, Carrier Female • 7. XhXh, Hemophiliac Female 8. XHY, Normal Male

10. 9. Label each problem as monohybrid, codominance, or X-linked. • What are the chances of a color blind woman and man with normal vision having daughters that are color blind? Being carriers? • Hitchhiker’s thumb is recessive to normal, straight thumbs. Write the F1 phenotypes for a cross between a heterozygous, straight thumbed father and a homozygous mother with hitchhiker’s thumb. 3. A pink flower is crossed with a pink flower. The resulting F1 offspring are 1 red, 2 pink, and 1 white. What are the genotypes of parents? Sex-Linked Monohybrid Codominant

11. 10. Using blood types, which children belong to which parents? • ParentsChildren • Parents 1  A- x B- Child A  A+ • Parents 2  AB+ x AB+ Child B  O – • Parents 3  A- x O+ Child C  B – • Parents 4  O+ x O+ Child D  AB+ • For blood type and Rh, assume heterozygous! Parents 1  Child C Parents 2  Child D Parents 3  Child A Parents 4  Child B

12. 11. Complete the following dihybrid cross. In pigs short snout is dominant over long snout and curly tails are dominant over straight tails. If two heterozygous short-snouted, heterozygous curly-tailed pigs are crossed, what are the probabilities of… a. Short-snouted, curly-tailed pigs? b. Short-snouted, straight-tailed pigs? c. Long-snouted, straight-tailed pigs? 9/16 3/16 1/16