Name:______

October 3, 2014 Gr.12 Biology: Genetics

Part A: Multiple Choice. Choose the BEST answer. (1 point each x 17= 17marks)

1. _____ Short fur in rabbits is dominant to long fur. What phenotypic ratio would you expect from a heterozygous female and a male with long fur ?

  1. 1:2:1
  2. 3:1
  3. 4:0
  4. 9:3:3:1
  5. 2:2

2. _____ The possible alleles for an individual that is heterozygous for a trait:

  1. Tt
  2. T
  3. t
  4. T, T
  5. T, t

3. _____ In dihybrid crosses, the ratio 9:3:3:1 illustrate ___.

  1. Codominance
  2. Independent assortment
  3. Segregation
  4. Three alleles for each trait

4. _____In a cross of a round hybrid pea with wrinkled parent (Ww x ww), what phenotypic proportions would be observed in the offspring?

  1. Half heterozygous, half homozygous recessive
  2. 50% round, 50% wrinkled
  3. 25% round, 75% wrinkled
  4. All round

5. _____ The fundamental Mendelian process which involves the separation of contrasting genetic elements at the same locus would be called ___.

  1. segregation
  2. independent assortment
  3. continuous variation
  4. discontinuous variation
  5. dominance or recessiveness

6. _____How many different genotypes would there be resulting from a dihybrid cross?

  1. 4
  2. 8
  3. 9
  4. 16

7. _____ Starting with a one-trait cross between two heterozygotes, the proportion of heterozygotes for that trait in the F1 progeny will be ___.

  1. 1/8
  2. 1/4
  3. 1/3
  4. 1/2
  5. All heterozygotes

8. _____ Albinism, lack of pigmentation in humans, results from an autosomal recessive gene. Two parents with normal pigmentation have an albino child. What is the probability that their next child will be albino?

A.100%

B.50%

C.25%

  1. 12.5%
  2. 0%

9. _____ A species of rabbits can have gray or black fur and long or short tails. A cross between pure-breeding black-furred, long-tailed mice and pure-breeding gray-furred, short-tailed mice produce all black-furred, long-tailed offspring. Which are the dominant phenotypes?

  1. Black fur and short tails
  2. Gray fur and short tails
  3. Black fur and long tails
  4. Gray fur and long tails

10._____ Using the information from question #9, determine the genotype that best fits the F1 generation.

  1. GGSS
  2. BBLL
  3. BbLl
  4. GgSs
  5. BbSs

11. _____ Referring to question 10, how many different types of gametes will the black-furred, long-tailed F1 mice produce?

  1. 1
  2. 2
  3. 4
  4. 16

12. _____ A test cross is used______.

  1. to determine the genotype of an organism showing the recessive trait.
  2. to determine the phenotype of an organism showing the dominant trait.
  3. to determine the genotype of an organism showing the dominant trait.
  4. to determine the phenotype of an organism showing the recessive trait.

13. _____ Which of the following conditions is/are X-linked recessive?

  1. Duchenne Muscular Dystrophy
  2. Tay Sachs Disease
  3. Hemophilia
  4. Sickle-cell disease
  5. Huntington’s Disease
  1. i and iv are both correct
  2. i and iii are both correct
  3. iii and v are both correct
  4. i, ii and iv are correct
  5. only iii is correct

14. ____ In a linkage group:

  1. All alleles are on one chromosome
  2. Tend to be inherited together
  3. If two traits are in one linkage group, then the cross will have similar results as if you had a one-trait cross
  4. Only two gametes are possible
  5. All of the above are true
  6. None of the above are true

15. ____ A Barr body:

  1. Explains what causes Down Syndrome
  2. Explains why a female with Turner Syndrome has a high probability of surviving
  3. is the extra active X chromosome in normal females
  4. Explains why poly-X females have a high probability of spontaneous abortion.

15. _____Blood type is an example of what type of inheritance pattern?

  1. incomplete dominance
  2. codominance
  3. polygenic inheritance
  4. multiple alleles
  5. all of the above

16. ____Down Syndrome is:

  1. trisomy 21
  2. caused by nondisjunction
  3. caused by crossing-over
  4. autosomal
  5. X-linked
  6. A,B, and E are true
  7. A, B and D are true
  8. A, C, and D are true
  9. A, C, and E are true

17. _____ Skin colour is an example of:

  1. codominance
  2. incomplete dominance
  3. polygenic inheritance
  4. multiple alleles
  5. none of the above

Part B: Short Answer (20 marks)

1. (3) A certain type of congenital deafness in humans is caused by a rare autosomal dominant gene. A mating involvies a deaf man and a deaf woman. Both are heterozygotes. They have four children. Could all the children have normal hearing? Explain using a Punnett square.What is the probability of having a normal hearing child from these parents?

2. (7) In Oompah-Loompahgenetics, being gray-faced is dominant over being orange faced. Purple, red, and blue hair colour exhibit incomplete dominance. If Olivia Oompah, who has an orange face and purple hair, has children with Oliver Oompah, who has is heterozygous for a gray face and blue hair, what proportion of their children will have a:

A. Gray face______

B. orange face______

C. Red hair ______

D. Purple hair ______

E. blue hair______

F. Gray faceand purple hair ______

G. Orange face and blue hair ______

3. (4) What are the 4 structural changes (mutations) that may occur during gamete formation? List them, and use diagrams to the mutations.

4. In the 1950’s, a young woman sued film star/director Charlie Chaplin for parental support of her illegitimate child. Charlie Chaplin’s blood type was already on record as type AB. The mother of the child had type A and her son had type O blood.

  1. (4) Complete a Punnett square(s) for the possible cross(es) of Charlie and the mother.
  1. (2) The judge ruled in favor of the mother and ordered Charlie Chaplin to pay child support costs of the child. Was the judge correct in his decision based on blood typing evidence? Explain why or why not using the information in your Punnett square(s).

Part C: Pedigree Analysis (8 points)

1.(8) For the pedigree below, determine whether the rare genetic condition is autosomal dominant, autosomal recessive or X-linked recessive. Explain the reason for your choice, as well as your reason for eliminating the other two options. There are four copies of the same pedigree for you to use in your analysis.

Part D: Long Answer

Answer 2of the following 3 questions (10 marks)

(I will only mark the twoquestions if you answer more than two.)

Be specific in your answers. Prove to me that you learned something this unit!

  1. (5) What is karyotyping? Explain what it is, and then explain the two methods of karyotyping we learned about in class, along with their risks and benefits.
  1. (5) Explain how sex-linked inheritance was at least a contributing factor inthe demise of many of the kingdoms of Europe.
  1. (5) Explain Armand Aubigny’s mistake in the case of Desiree’s baby.

Total: ____/55