Ecology of animals MCQs January 8, 2026March 13, 2024 by u930973931_answers 44 min Score: 0 Attempted: 0/44 Subscribe 1. In which biome would you expect to find the highest species diversity? (A) Tropical rainforest (B) Desert (C) Tundra (D) Temperate grassland 2. Which of the following is an example of a mutualistic relationship? (A) Bee pollinating a flower (B) Lion preying on a zebra (C) Tapeworm living in the intestines of a mammal (D) Parasitic fungus infecting a plant 3. What is the term used to describe the maximum population size of a species that its environment can sustain indefinitely? (A) Population threshold (B) Carrying capacity (C) Limiting factor (D) Density-independent factor 4. Which of the following is NOT a major greenhouse gas contributing to climate change? (A) Oxygen (O₂) (B) Methane (CH₄) (C) Nitrous oxide (N₂O) (D) Carbon dioxide (CO₂) 5. Which of the following is an example of an abiotic factor? (A) Predator-prey relationship (B) Temperature (C) Competition for food (D) Mutualism 6. Which term describes the process by which a population changes genetically over time in response to natural selection pressures? (A) Adaptation (B) Evolution (C) Migration (D) Genetic drift 7. Which of the following statements about keystone species is correct? (A) They have a minimal impact on their ecosystem (B) They play a disproportionate role in ecosystem structure (C) Their removal has little effect (D) They are usually the most abundant species 8. Which biome is characterized by low temperatures, permafrost, and a short growing season? (A) Temperate deciduous forest (B) Tropical rainforest (C) Taiga (boreal forest) (D) Temperate grassland 9. What term describes the range of environmental conditions under which an organism can survive and reproduce? (A) Habitat (B) Ecosystem (C) Niche (D) Tolerance range 10. Which of the following is NOT an example of a pioneer species? (A) Mosses (B) Lichens (C) Grasses (D) Shrubs 11. What is the primary source of phosphorus for terrestrial ecosystems? (A) Atmospheric deposition (B) Decomposition of organic matter (C) Weathering of rocks (D) Agricultural runoff 12. Which of the following terms refers to the movement of individuals into a population? (A) Emigration (B) Immigration (C) Natality (D) Mortality 13. Which of the following is an example of a biotic factor? (A) Temperature (B) Precipitation (C) Soil pH (D) Availability of food 14. In which type of symbiotic relationship do both species benefit? (A) Mutualism (B) Commensalism (C) Predation (D) Parasitism 15. What term describes the variety of different species within an ecosystem? (A) Ecosystem stability (B) Biodiversity (C) Population density (D) Community structure 16. Which of the following is an example of a density-dependent limiting factor? (A) Severe drought (B) Hurricane (C) Disease outbreak (D) Volcanic eruption 17. Which of the following is NOT a terrestrial biome? (A) Tundra (B) Desert (C) Grassland (D) Coral reef 18. What term describes the series of predictable changes that occur in a community over time? (A) Habitat fragmentation (B) Climax community (C) Population dynamics (D) Ecological succession 19. What is the primary source of energy for chemosynthetic ecosystems? (A) Sunlight (B) Organic matter (C) Soil nutrients (D) Hydrothermal vents 20. Which of the following is a density-independent factor that can influence population size? (A) Habitat destruction (B) Predation (C) Disease (D) Competition 21. What term describes the role a species plays in its ecosystem? (A) Niche (B) Habitat (C) Territory (D) Population 22. Which of the following best describes an ecosystem? (A) Community interacting with environment (B) Same species in one area (C) Physical environment only (D) Single species habitat 23. Which of the following is an example of a decomposer? (A) Rabbit (B) Hawk (C) Fungus (D) Grasshopper 24. What term describes the variety of habitats and ecological processes in the biosphere? (A) Biodiversity (B) Habitat fragmentation (C) Ecological footprint (D) Biome diversity 25. Which of the following best defines an ecosystem? (A) Living organisms only (B) Species interactions only (C) Physical and biological components interacting (D) Single species dynamics 26. Which of the following is NOT a major nutrient cycle? (A) Nitrogen cycle (B) Carbon cycle (C) Water cycle (D) Oxygen cycle 27. Which of the following is a density-dependent factor? (A) Earthquake (B) Food availability (C) Flood (D) Forest fire 28. What term describes when one species evolves to resemble another for benefit? (A) Symbiosis (B) Competition (C) Mimicry (D) Coevolution 29. Which of the following is an example of an invasive species? (A) Non-native species outcompeting natives (B) Native plant (C) Endangered species (D) Mutualistic species 30. Which factors contribute to stratification in aquatic ecosystems? (A) Temperature (B) Light availability (C) Nutrients (D) All of the above 31. What is the term for the total mass of living organisms in an ecosystem? (A) Biodiversity (B) Biomass (C) Trophic level (D) Carrying capacity 32. Which statement about primary succession is true? (A) Occurs where life existed (B) Faster than secondary succession (C) Lichens and mosses are pioneers (D) Begins in forests 33. What term describes the total number of species in an area? (A) Abundance (B) Stability (C) Diversity (D) Richness 34. Which is NOT a characteristic of a climax community? (A) Rapid species change (B) Stable populations (C) High diversity (D) Efficient nutrient cycling 35. What is the long-term average of weather patterns? (A) Biome (B) Microclimate (C) Weather (D) Climate 36. Which is a density-independent factor? (A) Competition (B) Nesting sites (C) Predation (D) Forest fire 37. What process returns nutrients to the soil from decomposing matter? (A) Photosynthesis (B) Respiration (C) Decomposition (D) Nutrient cycling 38. Which statement about ecological pyramids is true? (A) Biomass pyramid shows energy (B) Energy pyramid shows individuals (C) Biomass pyramid is always pyramid-shaped (D) Numbers pyramid is inverted 39. Which biome has permafrost and low precipitation? (A) Tundra (B) Taiga (C) Tropical rainforest (D) Desert 40. Which is a characteristic of r-selected species? (A) Long lifespan (B) Late reproduction (C) High reproductive rate (D) Large body size 41. What term describes conditions an organism can tolerate? (A) Tolerance range (B) Niche (C) Limiting factor (D) Habitat 42. What is the primary energy source for most ecosystems? (A) Wind (B) Sunlight (C) Geothermal energy (D) Biomass 43. Which is NOT a method of removing CO₂ from the atmosphere? (A) Photosynthesis (B) Fossil fuel combustion (C) Decomposition (D) Ocean absorption 44. What term describes the role of a species in its community? (A) Trophic level (B) Habitat (C) Niche (D) Ecosystem