Ecosystem MCQs for MDCAT Practice

Biology section, Ecosystem chapter. Sample questions from past PMC papers.

1. Question 1
   Which of the following statements is most consistent with the interactive hypothesis?
   • A.Communities lack discrete geographic boundaries
   • B.Species are distributed independently of other species
   • C.The community functions as an integrated unit
   • D.The composition of plant species seems to change on a continuum
   Sign up free to see the explanation, distractor analysis, and add this to your spaced repetition deck.
2. Question 2
   Which ecosystem has the maximum biomass?
   • A.Grassland ecosystem
   • B.Pond ecosystem
   • C.Lake ecosystem
   • D.Forest ecosystem
   Sign up free to see the explanation, distractor analysis, and add this to your spaced repetition deck.
3. Question 3
   The most appropriate method for estimating a population of a fixed plant species would be:
   • A.The random quadrant method
   • B.The ‘capture-recapture’ method
   • C.Estimating the percentage cover of the species
   • D.Drawing a line transect
   Sign up free to see the explanation, distractor analysis, and add this to your spaced repetition deck.
4. Question 4
   The distinct levels or links of food chain are called
   • A.Food web
   • B.Energy pyramid
   • C.Food chain
   • D.Trophic level
   Sign up free to see the explanation, distractor analysis, and add this to your spaced repetition deck.
5. Question 5
   Succession is a kind of
   • A.Community relay
   • B.Population relay
   • C.Ecosystem relay
   • D.Biosphere relay
   Sign up free to see the explanation, distractor analysis, and add this to your spaced repetition deck.
6. Question 6
   In Nitrogen cycle, conversion of Nitrates into nitrogen is termed as
   • A.Ammonification
   • B.Assimilation
   • C.Nitrification
   • D.Denitrification
   Sign up free to see the explanation, distractor analysis, and add this to your spaced repetition deck.
7. Question 7
   To measure the population density of monarch butterflies occupying a particular park, 100 butterflies are captured, marked with a small dot on a wing, and then released. The next day, another 100 butterflies are captured, including the recapture of 20 marked butterflies. One would correctly estimate the population to be:
   • A.20
   • B.100
   • C.200
   • D.500
   Sign up free to see the explanation, distractor analysis, and add this to your spaced repetition deck.
8. Question 8
   In which of the following habitats would you expect to find the largest number of K-selected individuals?
   • A.A recently abandoned field in Ohio
   • B.A newly emergent volcanic island
   • C.South Florida after a hurricane
   • D.The rain forests of Brazil
   Sign up free to see the explanation, distractor analysis, and add this to your spaced repetition deck.