Full Name: Period: 1 4 5 6 7 Heredity EOC Review Directions: For each genotype below, indicate whether it is a heterozygous (write: He) OR homozygous (write: Ho). 1. Tt BB DD ff tt dd dd Ff TT Bb bb FF Directions: Determine the phenotype for each genotype using the information provided. 2. Black body color is dominant to green. YY Yy yy 3. Pointy shape is dominant to flat. SS Ss ss Directions: Determine the genotype and phenotype for the trait: eye color (Y Blue, y green). 4. Genotype Phenotype Homozygous dominant Homozygous recessive Heterozygous 5. Directions: Circle the choices that are examples of each word. a. Dominant allele d e K L n o r s b. Recessive allele M N d F G n k P c. Homozygous (pure) dominant AA Gg kk mm PP rr TT Hh d. Homozygous (pure) recessive Ee Ff HH Oo qq Uu ww LL e. Heterozygous (hybrid) HH Rr aa Yy Bb LL tt Tt f. Offspring combinations in which dominant genes are expressed AA Dd EE ff Jj RR Ss kk g. Offspring combinations in which recessive genes are expressed aa Gg Ff KK Oo PP ss tt 1
For all of the following questions, use these facts: the trait is fur color (f). Black fur is dominant over gray fur. 6. Write the letter of the dominant allele. 7. Write the letter of the recessive allele. 8. Write out the homozygous dominant genotype (2 alleles). 9. Write out the heterozygous genotype (2 alleles). 10. Write out the homozygous recessive genotype. 11. Write the genotype for gray fur. 12. Write the genotype for Black fur. or Reminder: Trait: Fur color (F) BLACK fur is dominant over GRAY fur. 13. Write the phenotype for #19. 14. Write the phenotype for #20. 15. Write the phenotype for #21. Directions: Still using fur color, do the following monohybrid cross problems. 16. If the mother is homozygous recessive and the father is homozygous dominant. a) Write the genotype probabilities. b) Write the phenotype probabilities. 17. If the mother is heterozygous, and the father is heterozygous. a) Write the genotype probabilities. b) Write the phenotype probabilities. 2
18. If the mother is heterozygous, and the father is homozygous dominant. a) What percentage of the offspring are homozygous dominant? b) What percentage of the offspring are homozygous recessive? c) What percentage of the offspring are heterozygous? d) What percentage of the offspring are black? e) What percentage of the offspring are gray? 19. If the mother is homozygous recessive, and the father is heterozygous. a) What percentage of the offspring are homozygous dominant? b) What percentage of the offspring are homozygous recessive? c) What percentage of the offspring are heterozygous? d) What percentage of the offspring are black? e) What percentage of the offspring are gray? 20. In rabbits, the allele for black coat color (B) is dominant over the allele for brown coat color (b). If a heterozygous black rabbit is crossed with a brown rabbit, which of the following genotypic ratios can be expected? F 2 BB : 0 Bb : 2 bb G 1 BB : 2 Bb : 1 bb H 2 BB : 1 Bb : 1 bb J 0 BB : 2 Bb : 2 bb 3
21. A pea plant with the genotype TTmm is crossed with a pea plant with the genotype ttmm. Which of the following is not a possible gamete combination from either parent? F tm G tm H TM J Tm 22. Phenylketonuria (PKU) is an autosomal genetic disorder caused by a recessive allele (p). If a man and his wife are both carriers (heterozygous) for this disease, what is the probability that their first offspring will have the disorder? A 0% B 25% C 50% D 75% 23. Hemophilia is a sex-linked recessive disorder located on the X chromosome. For females to be a hemophiliac they must have F a copy of the allele on one of their X chromosomes. G a copy of the allele on both X chromosomes. H no copies of the allele. J inherited the trait only from their father. 24. In the diagram below, genetic material is being exchanged between chromosomes. This process, which occurs during meiosis, usually results in F a decrease in the number of chromosomes in the organism. G an increase in the number of gametes produces by the organism. H an increase in genetic variation found in the offspring of the organism. J the formation of identical twins. 4
25. Which of the cells below was not formed through the process of meiosis? F 1 G 2 H 3 J 1 and 2 5
Heredity Assessment 1. Hair color and eye color are examples of a person s: A. recessive traits B. dominant alleles C. genotype D. phenotype 2. One cat carries heterozygous, long-haired traits (Qq), and its mate carries homozygous short-haired traits (qq). Use a Punnett square to determine the probability of one of their offspring having long hair. A. 25% B. 50% C. 75% D. 100% 3. If a pea plant were homozygous recessive for height (T,t), how would its alleles be represented? A. Tt B. TT C. tt D. tt 4. In a certain species of pine trees, short needles (H) are dominant to long needles (h). What's the resulting phenotypic ratio if two heterozygous short pine trees are mated together? A. 1 HH : 2 Hh : 1 hh B. 3 Short : 1 Long C. 3 Long : 1 Short D. 1 Long : 2 Medium : 1 Short 5. In the flowering plant Ranunculus glacialis, the allele for yellow flower color (G) is dominant over the allele for white flower color (g). If the flower color characteristic is determined by a single gene, what is the expected outcome of crossing a plant heterozygous for yellow flowers and a plant with white flowers? A. 25% yellow; 75% white B. 50% yellow; 50% white C. 100% yellow D. 100% white 6