1. What is the term used to describe a relationship in which both species benefit?
(A) Commensalism
(B) Parasitism
(C) Mutualism
(D) Predation
2. Which of the following best describes an apex predator?
(A) A herbivore that feeds on plants
(B) A predator with no natural enemies
(C) A decomposer that breaks down organic matter
(D) An organism that scavenges for food
3. In a food web, which organisms are typically at the first trophic level?
(A) Primary consumers
(B) Secondary consumers
(C) Producers
(D) Tertiary consumers
4. Which species interaction involves one organism benefiting while the other is neither helped nor harmed?
(A) Parasitism
(B) Commensalism
(C) Mutualism
(D) Competition
5. What role do decomposers play in an ecosystem?
(A) They consume primary producers
(B) They convert solar energy into chemical energy
(C) They break down dead organisms and recycle nutrients
(D) They act as top predators
6. Which of the following is an example of a keystone species?
(A) A tree species that provides shade in a forest
(B) A plant species that produces many seeds
(C) A predator that helps regulate the population of prey species
(D) A decomposer that breaks down leaf litter
7. In a parasitic relationship, what is the organism that benefits called?
(A) Host
(B) Predator
(C) Symbiont
(D) Parasite
8. What is the primary role of herbivores in a food web?
(A) They decompose organic matter
(B) They produce their own food
(C) They consume producers
(D) They act as top predators
9. Which type of species interaction is characterized by both species being harmed?
(A) Parasitism
(B) Commensalism
(C) Competition
(D) Mutualism
10. What term describes the variety of feeding relationships that determine the flow of energy in an ecosystem?
(A) Food chain
(B) Food web
(C) Trophic level
(D) Energy pyramid