Chapter 11: Review Questions

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Question 1

1. What is environmental health?

  1. Environmental health refers to the level of biodiversity in an ecosystem.

  2. Environmental health is determined by how close the actual primary production in an ecosystem is to its potential.

  3. Environmental health is a field of study concerned with how environmental factors affect human health and safety.

  4. Environmental health refers to how comfortable people feel in an environment.

Question 2

2. Which of the following interactions between two toxic substances results in a level of toxicity much greater than the sum of their individual toxicities?

  1. Antagonistic effects

  2. Synergystic effects

  3. Additive effects

  4. Hyper effects

Question 3

3. Approximately what percentage of the cells in your body are human?

  1. 100%

  2. 75%

  3. 50%

  4. 10%

Question 4

4. Which of the following classes of toxic substances are most likely to show bioaccumulation?

  1. Water-soluble toxic substances

  2. The various types of alcohols

  3. The metallic form of mercury

  4. Methyl mercury, an organic form of mercury

Question 5

5. Why are endocrine disruptors an especially serious class of toxic substances?

  1. They affect a wide range of organisms.

  2. They occur in so many common products.

  3. They can alter sexual development.

  4. All of the above

Question 6

6. Which of the following conditions contributes to the evolution of antibiotic resistance in bacteria populations?

  1. Small population size where mutations are more likely to occur

  2. Infrequent exposure to antibiotics, which allows resistance to build up in the population

  3. Patients always completing a full course of treatment with antibiotics

  4. Frequent exposure to antibiotics, which exert strong natural selection favoring resistance

Question 7

7. What is the meaning of an LD50 in a dose–response test?

  1. An LD50 is half the lethal dose of a toxic substance.

  2. An LD50 is the dose that is lethal to the population after 50 hours.

  3. An LD50 is the dose that kills half the test population.

  4. An LD50 is the percentage of the population killed by a lethal dose.

Question 8

8. Why are access to sanitation and clean water serious environmental issues?

  1. Sanitation and clean water are engineering problems, not environmental health issues.

  2. Access to sanitation and clean water are social problems, not environmental health issues.

  3. Access to sanitation and clean water are not environmental health issues because those basic necessities were addressed long ago.

  4. Millions of people die each year because their environment does not provide access to sanitation and clean water.

Question 9

9. Why is treating and controlling the spread of tuberculosis (TB) as much a social problem as it is a medical problem?

  1. Poor nutrition and crowded living conditions increase the likelihood of contracting TB.

  2. Ensuring completion of treatment often requires careful guidance by caregivers.

  3. Contact with individuals infected with TB is a common way to contract the disease.

  4. All of the above

Question 10

10. How much has decreased use of antibiotics and more attention to prevention of disease increased the cost of livestock production in Denmark?

  1. 1%

  2. 5%

  3. 15%

  4. 25%

Critical Analysis

Question 1

1. What basis is there for considering individual humans as ecosystems or complex ecological communities? How might these ecological concepts contribute to managing human health?

Question 2

2. How are DDT and mercury pollution similar? How are they different?

Question 3

3. How should the precautionary principle be applied to the release of chemicals into the environment? Include detailed conditions for invoking the precautionary principle.

Question 4

4. Outline and explain in detail the elements of a chemical risk assessment.

Question 5

5. Discuss how the health of individuals is largely determined by the interaction between their genome, their genetic makeup, and their exposome.