Chapter 9 Objective Questions

Chapter 9 Objective Questions

1. If one performs radiocarbon dating on a living oyster, the date obtained indicates that the oyster is over a thousand years old. This result reflects the fact that:
- a. the oyster was a fossil
- b. the oyster shell's carbon is recycled from oysters that lived thousands of years ago
- c. the procedure was carried out incorrectly
- d. radiocarbon dating is not accurate
- e. oysters live a long time

2. Charles Darwin sailed around the world on a ship called H.M.S.
- a. Challenger
- b. Santa Maria
- c. Pinafore
- d. America
- e. Beagle

3. Assume that the allele X is completely dominant to the allele x and that the frequency of recessive homozygotes in a population is 16%. What is the frequency of allele X?
- a. 4%
- b. 0.6%
- c. 6%
- d. 25%
- e. 0.04%

4. A key contribution to Darwin's thinking was the Malthus concept that populations grow:
- a. arithmetically
- b. without limit
- c. only as fast as the environment will support them
- d. until they reach a certain maximum size determined by their reproductive potential
- e. geometrically

5. According to the theory of kin selection, altruism is most likely to be directed towards:
- a. close relatives
- b. friends
- c. strangers
- d. rivals
- e. enemies

6. Imagine you were attempting to date an old skull by carbon 14 methods. Assume the atmospheric ratio of C-14 to C-12 is one molecule of C-14 to every 999 molecules of C-12 (that is, the proportion of C-14 is 1 in 1000 or 0.001), and that the half life of C-14 is 6000 years. How old is the skull if its proportion of C-14 is 0.00025?
- a. 3000 years
- b. 18,000 years
- c. 6000 years
- d. 12,000 years
- e. 9000 years

7. Melanic moths are often cited as providing evidence for Darwin's theory of evolution. When a scientist named Kettlewell released equal numbers of melanic and grey moths in highly-industrialized Birmingham, England, what happened?
- a. all of the moths got eaten by birds
- b. the grey ones got eaten by birds far more frequently than the mellanic ones
- c. equal numbers of melanic and grey moths got eaten by birds
- d. neither grey nor melanic moths were eaten by birds
- e. the melanic ones got eaten by birds far more frequently than the grey ones

8. Assume that a human population has two alleles of a gene determining the nature of a red blood cell surface protein, that the two alleles are designated M and N, and that the N allele occurs in the frequency 0.40 within this population. If no significant evolutionary pressures are acting on this population (like selection, migration, inbreeding, or genetic drift), what would you expect the proportion of heterozygous individuals in the population to be?
- a. 16%
- b. 48%
- c. 24%
- d. 52%
- e. 60%

9. Creationists argue that life could not have originated in a "primordial soup" for the simple reason that proteins would never have spontaneously assembled in such a soup. What is the basis for their argument?
- a. there is not enough energy in water for the reaction to occur
- b. the reaction is irreversible in the direction of protein breakdown
- c. left-handed amino acids will not associate with right-handed amino acids
- d. there were not enough amino acids present for it to be likely that one amino acid molecule would encounter another
- e. the reaction is freely reversible, with water a product of protein formation

10. Scientists (except Duane Gish and other "scientific creationists") believe that life evolved on earth how many years ago?
- a. 4.5 billion
- b. 3.5 billion
- c. 1.5 billion
- d. 65 million
- e. 6000

11. Darwin's early thinking about natural selection was stimulated by reading a book by a clergyman. Who was the clergyman?
- a. Chambers
- b. Malthus
- c. Wilburforce
- d. Wallace
- e. Huxley

12. Sickle cell anemia is a defect in the gene encoding hemoglobin. In parts of Central Africa up to 45% of individuals are heterozygous for this defective form of the gene. Why?
- a. It is carried by mosquitoes, which are very common in Central Africa
- b. More people live in Central Africa than in other parts of Africa
- c. Heterozygous individuals are more resistant to malaria, common in Central Africa
- d. Like AIDS, also common in Central Africa, the disease is spread sexually
- e. Heterozygous carriers do not express the disease but are fully infectious

13. You analyze the meat in a MacDonald's hamburger and find the ratio of carbon-14 to carbon-12 to be 0.00124. You similarly analyze a bone you found on a plate at the RAT, and obtain a ratio of 0.00031. Knowing the half life of carbon-14 to be 5730 years, how many years old is the bone?
- a. 5,730
- b. 11,460
- c. 17,190
- d. 22,920
- e. 1

14. Mutations that occur in nature are usually:
- a. disadvantageous
- b. neutral
- c. advantageous

15. Objections to the validity of radiometric dating include the observation that marine life near deep sea vents are millions of years old by C14 dating. This observation is explained by the fact that deep sea vent ecosystems get most of their carbon from ________________ seeping from the vents.

16. Although sickle cell anemia is a debilitating heritable disease in the homozygous state, its incidence in tropical regions is high because in the heterozygous state this genetic defect gives protection against the disease ___________________.

17. Darwin used the following as evidence for his theory of evolution EXCEPT:
- a. fossil records
- b. geographic distribution of closely related groups
- c. radio dating of rock strata
- d. genetic variability in populations

18. Darwin cited the variance in breed pigeons as:
- a. survival of the fittest
- b. genetic variability in populations
- c. struggle for insufficient resources
- d. evolution of new species

19. Darwin and Wallace were profoundly influenced by Thomas Malthus Essay on the Principles of Population. In this book Malthus points out that populations of plants and animals tend to:
- a. increase arithmetically
- b. increase geometrically
- c. adjust to food supplies
- d. b and c above

20. Assume that the allele A is completely dominant to the allele a, and that the frequency of recessive homozygote's in a population is 16%. What is the frequency of allele A?
- a. 4%
- b. 0.04
- c. 0.6
- d. 6%
- e. 3:1

21. Assume that a human population has two alleles of a gene determining the nature of a red blood cell surface protein, that the two alleles are designated M and N, and that the N allele occurs in the frequency 0.40 within this population. If no significant evolutionary pressures are acting on the population (like selection, migration, inbreeding, or genetic drift), what would you expect the proportion of heterozygous individuals in the population to be?
- a. 16%
- b. 60%
- c. 48%
- d. 24%