Biotic and abiotic factors Knowledge-Based Practice

Questions

1. 1.

   Which of the following environmental variables is an abiotic factor that directly regulates the metabolic rate of ectothermic animals?

   • A) Pathogen prevalence
   • B) Ambient environmental temperature
   • C) Interspecific food competition
   • D) Predation pressure
2. 2.

   Which of the following is an abiotic factor that directly limits the vertical distribution of photosynthetic organisms in a deep freshwater lake?

   • A) Grazing pressure exerted by herbivorous fish
   • B) Light penetration through the water column
   • C) Competition among phytoplankton species for space
   • D) Decomposition of organic detritus by benthic bacteria
3. 3.

   Which of the following factors regulating the size of a woodland herbivore population is classified as a biotic factor?

   • A) Seasonal fluctuations in ambient temperature
   • B) Annual volume of atmospheric precipitation
   • C) Presence of predatory mammals and pathogenic microorganisms
   • D) Concentration of dissolved mineral nutrients in the soil
4. 4.

   Which of the following is an example of a biotic factor directly altering an abiotic factor in an ecosystem?

   • A) Plant roots breaking bedrock apart and altering the physical composition of the soil
   • B) A predatory bird hunting rodents to regulate prey population numbers
   • C) Intense sunlight increasing the rate of water evaporation from a lake surface
   • D) A sharp drop in ambient air temperature causing reptiles to lower their metabolic rate
5. 5.

   Which of the following consists exclusively of abiotic factors that influence living organisms in an ecosystem?

   • A) Soil bacteria, ambient temperature, and precipitation
   • B) Solar radiation, annual precipitation, and soil pH
   • C) Phytoplankton, water salinity, and dissolved oxygen
   • D) Decomposers, wind velocity, and atmospheric nitrogen

Answers and step-by-step solutions appear after you finish the test.