1. What is an estuary? It is _______________.
A. an area where solid rocks are found
B. a mixture of saltwater and freshwater
C. where mud from sea and rivers were deposited
D. an area where filled with seawater during high tide and drained during low tide
2. Which of the following does NOT describe an estuary?
A. exit points for floods
B. filter sediments and pollutants
C. can only be found in warm climate
D. brackish water comes together at the river mouth
3. What do living and non-living things do in an ecosystem?
A. die
B. interact
C. live
D. multiply
4. Which of the following area where mud from the seas or rivers is deposited?
A. coral reefs
B. mangrove forests
C. mud flats
D. salt marshes
5. Which of the following is a biotic factor?
A. animals
B. microorganisms
C. plants
D. all of the above
6. Which is a living thing that eats other animals?
A. carnivores
B. decomposers
C. herbivores
D. producers
7. Which is also called “nurseries of the seas?”
A. coral reefs
B. intertidal zone
C. estuaries
D. mangrove
8. Which of the following organisms is a decomposer?
A. algae
B. bacteria
C. kelp
D. seaweeds
9. How do mangroves forest help in the intertidal and estuarine ecosystems? Mangroves forests _____________.
A. protect the coast against erosion by waves, winds, and tides
B. fertilize the estuaries and intertidal areas
C. increase population of organisms
D. give an unhealthy environment
10. Why are decomposers important? Because they _________.
A. make their own food
B. eat both plants and animals
C. break down dead organisms and wastes
D. get their energy by feeding on plants and animals