CHAPTER 30: Ecotoxicology

Chapter 30. Ecotoxicology

What is the mode by which a chemical enters the lithosphere?

a. evaporation.

b. adsorption.

c. dissolution.

d. absorption.

e. diffusion.

The bioavailability of contaminants in the hydrosphere is directly related to:

a. chemical concentration.

b. amount of chemical.

c. water solubility of chemical.

d. toxicity of chemical.

e. molecular size of chemical.

All of the following regarding biomarkers are true EXCEPT:

a. Dermal absorption is considered an external dose.

b. Biomarkers of susceptibility are useful in extrapolating wildlife disease to human diseases.

c. Induction of certain enzymes is an important biomarker.

d. The biologically effective dose is the amount of internal dose needed to elicit a certain response.

e. The effects of chemical exposure can be different across species.

Which of the following processes is LEAST likely to be affected by endocrine-disrupting agents?

a. enzyme activity.

b. transcription.

c. hormone secretion.

d. signal transduction.

e. DNA replication.

Estrogen exposure has been shown to cause all of the following in wildlife species EXCEPT:

a. sexual imprinting.

b. altered sex hormone levels.

c. immune suppression.

d. gonadal malformations.

e. sex reversal.

Which of the following is FALSE regarding terrestrial ecotoxicology?

a. Terrestrial organisms are generally exposed to contaminants via ingestion.

b. Predation is an important confounder of measurements in terrestrial toxicology field studies.

c. Reproductive tests are not important in measuring end points in toxicity tests.

d. Enclosure studies are better able to control for environmental factors in field studies.

e. Toxicity tests usually test the effects of an oral chemical dose.

An important type(s) of compound that is far more toxic in water than in air is/are: