IB BIO I Genetics Test Madden

Transcription

1 Name Date Multiple Choice 1. What does the genotype X H X h indicate? A. A co-dominant female B. A heterozygous male C. A heterozygous female D. A co-dominant male 2. A pure breeding tall plant with smooth seeds was crossed with a pure breeding short plant with wrinkled seeds. All the F 1 plants were tall with smooth seeds. Two of these F 1 plants were crossed and four different phenotypes were obtained in the 320 plants produced. How many tall plants with wrinkled seeds would you expect to find? A. 20 B. 180 C. 60 D If a purple flowered (Pp) and a white flowered pea plant (pp) are crossed, what will the offspring be? A. 1 : 1 ratio of purple and white flowers B. 3 : 1 ratio of purple to white flowers C. 1 : 3 ratio of purple to white flowers D. All purple flowers 4. Humans are in blood group M, N or MN. The alleles for blood group M (M) and blood group N (N) are co-dominant. Humans are also in blood group A, B, AB or O. The alleles controlling these blood groups are I A, I B and i. If two parents have the genotypes ii MM and I A i MN what is the ratio of possible phenotypes of their offspring? A. 9 group A, group M 3 group A, group N 3 group O, group M 1 group O, group N B. 9 group O, group M 3 group O, group N 3 group A, group M 1 group A, group N C. 3 group O, group M 3 group O, group MN 1 group A, group M 1 group A, group MN D. 1 group A, group M 1 group A, group MN 1 group O, group M 1 group O, group MN 1

2 5. The pedigree below shows which members of a family were Rhesus positive ( and ) and Rhesus negative ( and O). The allele for Rhesus positive blood (Rh + ) is dominant over the allele for Rhesus negative blood (R - ). I II III Rhesus positive male Rhesus negative male Rhesus positive female Rhesus negative female Which are possible genotypes of the individuals numbered I, II and III? I II III A. Rh + Rh + Rh + Rh + Rh + Rh B. Rh + Rh + Rh + Rh Rh + Rh + C. Rh + Rh + Rh + Rh Rh + Rh D. Rh + Rh Rh + Rh Rh + Rh + 6. Which human trait shows a pattern of polygenic inheritance? A. ABO blood type B. Sickle cell anemia C. Skin colour D. Co-dominant alleles 7. A single gene in humans causes blood to be either rhesus positive (dominant allele) or rhesus negative (recessive allele). A woman with rhesus negative blood has already had a child with rhesus positive blood. There could be complications during pregnancy if she has another child with rhesus positive blood. What is the probability of this, if the father (a heterozygote) is the same, and if his mother is known to have rhesus negative blood? A. 25% B. 50% C. 75% D. 100% 2

3 8. Mendel crossed pure breeding (homozygous) tall pea plants that had coloured flowers with pure breeding dwarf pea plants that had white flowers. All of the resulting F 1 plants were tall and had coloured flowers. If Mendel had crossed these F 1 plants with a pure breeding strain of dwarf pea plants with coloured flowers, what proportion of tall coloured plants would be expected in the offspring? A. B. C. D In Drosophila the allele for normal wings (W) is dominant over the allele for vestigal wings (w) and the allele for normal body (G) is dominant over the allele for ebony body (g). If two Drosophila with the genotypes Wwgg and wwgg are crossed together, what ratio of phenotypes is expected in the offspring? A. 9 normal wings, normal body : 3 normal wings, ebony body : 3 vestigal wings, B. 3 normal wings, normal body : 3 normal wings, ebony body : 3 vestigal wings, C. 3 normal wings, normal body : 1 normal wings, ebony body : 3 vestigal wings, D. 1 normal wings, normal body : 1 normal wings, ebony body : 1 vestigal wings, 10. What is a sex-linked gene? A. A gene whose locus is on the X chromosome only. B. A gene whose locus is on the X or Y chromosomes. C. A gene whose locus is on the both X and Y chromosomes. D. A gene whose locus is on the Y chromosome only. 3

4 11. Which of the following blood group phenotypes always has a homozygous genotype? A. A B. B C. AB D. O 12. What feature demonstrates codominance in the inheritance of ABO blood groups? A. When I A and I B alleles are expressed in heterozygotes. B. When I A and I A alleles are expressed in homozygotes. C. When I B and I B alleles are expressed in homozygotes. D. When I A and i alleles are expressed in heterozygotes. 13. A woman has a heterozygous genotype for blood group B. She is expecting a baby with a man who is homozygous Group A. What are the possible blood groups for their baby? I. Group O II. III. Group A Group AB A. II and III only B. I and II only C. I and III only D. I, II and III 14. What is the genetic cross called between an individual of unknown genotype and an individual who is homozygous recessive for a particular trait? A. Test-cross B. Hybrid cross C. Dihybrid cross D. F1 cross 4

5 15. The following diagram represents a two generation pedigree showing the blood groups of the individuals. The female has been married to two different individuals. 1st generation 2nd generation O A AB B O A AB Key Male Female (a) (b) Define the term co-dominant alleles. Deduce with a reason the probable father of 2nd generation 1. (c) If 2nd generation 3 marries a man with blood group AB, predict the possible genotypes of the children. (3) (Total 6marks) 16. The diagram below shows the pedigree of a family with red green colour-blindness, a sex-linked condition. 1st generation 2nd generation Key normal male normal female male with condition female with condition 3rd generation (a) (b) Define the term sex-linkage. Deduce, with a reason, whether the allele producing the condition is dominant or recessive. (c) (i) Determine all the possible genotypes of the individual (2nd generation 1) using appropriate symbols. (ii) Determine all the possible genotypes of the individual (3rd generation 4) using appropriate symbols. 5

6 (Total 5 marks) 17. (a) A farmer has rabbits with two particular traits, each controlled by a separate gene. Coat color brown is completely dominant to white. Tailed is completely dominant to tail-less. A brown, tailed male rabbit that is heterozygous at both loci is crossed with a white, tailless female rabbit. A large number of offspring is produced with only two phenotypes: brown and tailed, white and tail-less, and the two types are in equal numbers. (i) (ii) Describe the pattern of inheritance of these traits. State both parents genotypes and the gametes that are produced by each during the process of meiosis. Male genotype:... Female genotype:... Male gametes:... Female gametes:... (iii) Predict the genotypic and phenotypic ratios of the F2 generation. Show your working. (Total 6 marks) 18. Define the terms gene and allele and explain how they differ. (Total 4 marks) Bonus: Outline one example of inheritance involving multiple alleles. 6