Unit 1 Midterm Test Bank

Non-Essay Questions (Moodle will randomly choose 15 of these for your midterm. They are worth 1 point each).

1. Define gene flow

2. Definite genetic drift

3. Define phenotype

4. Hemophilia is a sex-linked trait, caused by a recessive allele on the X chromosome. The last crown prince of Russia, Alexi, was a hemophiliac. His mother and father did NOT have hemophilia. Did any of his sisters? In one or two sentences, please explain how you arrived at your answer.

5. Name two assumptions of the Hardy-Weinberg genetic equilibrium

6. Define evolution

7. Both religious and scientific narratives can be valid ways of understanding the world. However, these narratives have different standards for determining what is true or valid. In one or two sentences, explain the differences between scientific and religious narratives and the basis on which people accept or reject them.

8. Define a Mendelian trait. Give an example.

9. If two alleles are codominant, how would you describe the phenotype of a person who has one of each?

10. What does the Heritability Index measure?

11. In two populations in different parts of the world, the HI for height is 0.8. However, in the first population, the average height of men is 5'6", and in the second population the average height is 6'. In 2 or 3 sentences, explain why it is not possible to say that the men in the first population are genetically determined to be shorter than men in the second population.

12. In one or two sentences, explain the difference between bias and racism.

13. Define a cline

14. Physical traits that occur because you were born and raised in a stressful environment (very cold, very hot, or high altitude) are called: _______. These traits remain with you your entire life, but are not inherited by your children

15. Phenotypic _____________ refers to the flexibility of our expressed traits in response to the environment.

16. The only sources of new genetic material for a species is:

17. The dark fur on a Siamese cat's ears and paws is created by the same cells that make light fur on the cat's body. The effect of body temperature on pigmentation is an example of how ___________ is affected by environmental context

18. Unexpressed segments of DNA are called:

19. The majority of sex-linked traits are found on the ___ chromosome.

20. The two steps of protein synthesis are _______ and translation.

21. What does a gene do or make?

22. Most genes are ______________, meaning they affect many traits in a person's phenotype, not just one.

23. Most human traits are _______________, meaning they are affected by many different genes.

24. Allele R codes for red pigment in a flower, and allele Y codes for yellow pigment. If a flower has genotype RY, it will be orange. This is an example of ______ _______.

25. The parts of the DNA strand that are expressed are called:

26. The second stage in creating a protein from DNA, when the RNA connects amino acids outside the nucleus of the cell, is called ______________

27. The amount of variation in a trait that can be accounted for by genetic differences is a trait's ____________

28. Anthropologist define ________ ________ as the genetic and phenotypic variation in humans around the globe.

    1. _____________ is a system of categories that cultures place on top of continuous human diversity.

29. The dominant allele R codes for "asparagus urine", a condition where a person's urine smells strongly of asparagus after eating it. (Yes, this is a real thing. Honestly.) R is 60% of the alleles in the population on a remote Pacific island.

• 1. If R and r are the only possible alleles, what is the frequency of the allele r? _____%

  2. What are the expected percentages of the three possible genotypes in the next generation?

     1. RR ________ %

     2. Rr ________%

     3. rr ________%

  3. If the actual frequency for homozygous recessive in the second generation is 25%, how would you interpret the results?

• • 1. No evolution has occurred, that is the frequency we would expect

    2. Evolution has occurred, allele frequencies have changed

    3. One of the assumptions of Hardy-Weinberg has been violated

    4. 2 and 3 are both true

30. The dominant allele K is 40% of alleles in a population.

    2. 1. If K and k are the only possible alleles, what is the percentage of the allele k? _____%

       2. What are the expected percentages of the three possible genotypes in the next generation?

          1. KK _____%

          2. Kk _____%

          3. kk _____%

• 1. If the actual frequency for homozygous recessive in the second generation is 25%, how would you interpret the results?

     1. No evolution has occurred, that is the frequency we would expect

     2. Evolution has occurred, allele frequencies have changed

     3. One of the assumptions of Hardy-Weinberg has been violated

     4. 2 and 3 are both true

31. The dominant allele E leads to yellow, sticky ear wax, while the allele e leads to white, crumbly ear was. (Yes, this really is a thing. I swear.) If a homozygous dominant individual had children with a homozygous recessive person, what would the resulting offspring look like? (You may want to draw a Punnett Square of this scenario on scrap paper, just for your reference. You don't need to turn it in.)

• 1. What are the expected percentages of genotypes in the offpsring?

     1. 1. EE _____%

        2. Ee _____%

        3. ee _____%

• • 1. What are the expected percentages of phenotypes in the offspring?

       1. Yellow and sticky ear wax _____%

       2. White and crumbly ear was _____%

    2. Which of the following is true about the offspring?

• • • 1. They will all be homozygous and show the dominant phenotype

      2. They will all be heterozygous and show the dominant phenotype

      3. They will all be homozygous and show the recessive phenotype

      4. They will be a mix of homozygous and heterozygous genotypes

• 2. Human blood type is determined by three possible alleles: A, O, and B. A and B are both dominant, while O is recessive. Cersei has genotype AO, and her son, Joffrey, has blood type AB. (Please note: you do not have to have read any popular novels or seen any HBO television shows to answer this question. You have all the information you need right here.)

• • 1. Using just the information above, what are the three possible genotypes for Joffrey's father?

       1. ______

       2. ______

       3. ______

    2. Cersei has a daughter, Myrcella, who is Joffrey's full sister. She has blood type O. With this additional information, what must her father's genotype be? _____

    3. What are the possible genotypes for Myrcella and Joffrey's full brother, Tommen?

• • • 1. _____

      2. _____

      3. _____

      4. _____

• • 4. If Cersei were to have more children with the same man, what percentage of the children would be expected to have type AB blood? _____%

    5. Which of these men could possible be the father of Joffrey, Myrcella, and Tommen?

• • • 1. Robert, type O blood

      2. Jaime, type B blood

      3. Osney, type A blood

      4. Lancel, type AB blood

• 3. The dominant allele E creates an external structure on red blood cells. People with genotype ee lack this structure. An international team of researchers are investigating whether the lack of that external structure may make an individual less susceptible to malaria. (In other words, ee individuals survive better in malarial environments.) In the current generation, the frequency of the homozygous recessive genome is 0.16.

• • 1. What is the frequency of e in the current generation? _____

    2. What is the frequency of E in the current generation? _____

    3. The research team is measuring the frequencies of E and e in a population where malaria is a frequent health risk. Which of these scenarios could support the researcher's hypothesis that individuals whose red blood cells lack the external structure are less susceptible to malaria?

       1. The frequency of allele e in the next generation is 0.6

       2. The frequency of allele e in the previous generation (parents of the current generation) was 0.2

       3. In the previous generation, the frequency of the recessive phenotype was 10%

       4. All of the above

    4. If the actual frequency for the heterozygous genotype in the next generation is 0.35, how would you interpret the results?

    5. No evolution has occurred, that is the frequency we would expect

    6. Evolution has occurred, allele frequencies have changed

    7. One of the assumptions of Hardy-Weinberg has been violated

    8. 2 and 3 are both true

32. In a given population of petunias, the allele for red pigment (R) is incompletely dominant over the allele for white pigment (w). If 200 petunias are red, 75 are pink, and 25 are white, what are the allele frequencies in this population (that is, what are p and q)?

• 1. Frequency of R _____%

  2. Frequency of w _____%

33. A large population of captive crumple-horned snorkacks has 396 individuals without stripes and 557 individuals with stripes. Stripes are a Mendelian trait, and the allele that creates tripes (T) is dominant over the allele that does not code for stripes (t).

• 1. What is the frequency of allele T (round to nearest whole number)? _____%

  2. What is the frequency of allele t (round to nearest whole number)? _____%

  3. What percentage of heterozygotic snorkacks do you expect in this population (round to the nearest whole number)? _____%

34. In humans, blood type is a result of multiple alleles: A, B, and O. A and B are both dominant over O. A and B are codominant with each other. Two parents are heterozygous for type A blood and they have sickle-cell trait, meanting they have one dominant allele for normal-shaped blood (S), and one recessive allele for sickle-shaped blood (s).

• 1. What is the genotype of both parents? _____

  2. What are the genetic makeups of all the possible gametes they can produce? _____

  3. What is the expected frequency of children who will have blood type O and sickle cell trait? _____%

35. In Population A, anthropologists measured height in parents and their children. They collected the following data:

In Population B, anthropologists also measure height in parents and their children. They collected the following data:

In which of these populations does height show greater heritability? ______

Essay Questions (Moodle will randomly choose two of these for your midterm. They are worth 5 points each)

1. Your doctor orders a genetic test, and later informs you that you have a gene for Altzheimer's. What information about the expression of this gene do you need to know, to help you better understand the meaning of this report? Under what conditions should you be most concerned?

2. What is natural selection? What characteristics must a trait have to be subject to natural selection and why is each one necessary? Give an example of how natural selection works.

3. Explain why race is not a biological category. Your answer should include an explanation of why race does not reflect human diversity, and an explanation of what it means to say race is a “social construct”, that is, how can we tell it is socially defined?

4. In what ways do genes and the environment interact? Which types of traits appear to be highly controlled by your genes, and which by environmental influences? Give examples.

5. What is the equation for the Hardy-Weinberg theory of genetic equilibrium? List the five assumptions that must be met in an idealized population at equilibrium and explain what each one means.

6. Explain why anthropologists argue that the phrase "human differences are only skin deep" is misleading, both biologically and socially. Use examples from lecture, readings, or personal experience.

7. What is Evolution (define fully!)? Why is it not the same as Natural Selection? Give examples from lecture, readings, or personal experience.