1.
Freshwater biomes have
Correct Answer
B. Less than 1% salt
Explanation
Freshwater biomes are characterized by having a low salt concentration, typically less than 1%. This is because freshwater biomes include bodies of water such as lakes, rivers, and ponds, which are primarily fed by freshwater sources like rainfall, melting snow, and underground springs. These sources do not contain a high amount of dissolved salts, resulting in a low salt content in freshwater biomes. The low salt concentration is essential for the survival of many freshwater organisms, as they have adapted to these conditions over time.
2.
What are estuaries?
Correct Answer
B. A partially enclosed, coastal water body where a freshwater river or stream meets the ocean.
Explanation
Estuaries are partially enclosed, coastal water bodies where a freshwater river or stream meets the ocean. They are characterized by the mixing of saltwater and freshwater, creating a unique ecosystem that supports a diverse range of plant and animal species. Estuaries are important habitats for many species, serving as nurseries for fish and providing feeding grounds for migratory birds. The mixing of freshwater and saltwater in estuaries also helps to filter pollutants and improve water quality.
3.
A water body having water saltier than fresh water but not as salty as seawater is called a?
Correct Answer
B. Brackish water body
Explanation
A water body that is saltier than fresh water but not as salty as seawater is called a brackish water body. Brackish water is a mix of freshwater and seawater, usually found in estuaries, coastal marshes, and lagoons. It has a higher salinity than freshwater, but lower salinity than seawater. This unique combination of salinity makes it a distinct type of water body, supporting a unique ecosystem with specific species adapted to survive in this intermediate salinity range.
4.
Animals that live on the sea floor are called
Correct Answer
A. Benthic
Explanation
The correct answer is "Benthic." Benthic refers to animals that live on the sea floor. The term "pelagic" refers to animals that live in the water column, away from the sea floor. Therefore, the correct answer is "Benthic" because it specifically describes animals that live on the sea floor.
5.
Lentic water is
Correct Answer
B. Standing water
Explanation
Lentic water refers to still or standing water bodies such as lakes, ponds, and marshes. These water bodies are characterized by their lack of significant movement or flow. Unlike lotic water, which refers to flowing water bodies like rivers and streams, lentic water remains relatively stagnant. This can lead to unique ecological conditions and the development of specific plant and animal communities adapted to this type of environment. Therefore, the correct answer is "Standing water."
6.
Actively swimming aquatic organisms in a body of water are called
Correct Answer
C. Nekton
Explanation
Nekton refers to actively swimming aquatic organisms in a body of water. This term includes larger and more mobile organisms such as fish, turtles, and whales, which are capable of independent movement against the current. Neuston refers to organisms that live on or just below the water surface, Periphyton refers to organisms that attach to surfaces in the water, and Plankton refers to organisms that drift or float in the water column. Therefore, Nekton is the correct answer as it specifically describes the actively swimming organisms in a body of water.
7.
Earth consists of
Correct Answer
B. ~70% water
Explanation
The correct answer is ~70% water. This is because Earth is predominantly covered by water bodies, such as oceans, seas, lakes, and rivers. These water bodies make up approximately 70% of the Earth's surface. Additionally, water is also present in the form of ice in polar regions and as groundwater beneath the Earth's surface.
8.
_____ contain maximum proportions of fresh water.
Correct Answer
C. Glaciers and Ice Caps
Explanation
Glaciers and ice caps contain maximum proportions of fresh water. Glaciers are large bodies of ice formed from compacted snow that accumulate over many years. They store about 69% of the world's fresh water, making them the largest reservoir of freshwater on Earth. Ice caps are smaller versions of glaciers and also contribute to the fresh water supply. Groundwater, lakes, and rivers also contain fresh water, but glaciers and ice caps have the highest concentration.
9.
Which of the following is not a type of coral reef?
Correct Answer
D. Transitioning reefs
Explanation
Transitioning reefs is not a type of coral reef. The given options include barrier reefs, fringing reefs, and atolls, all of which are recognized types of coral reefs. Barrier reefs are parallel to the shoreline with a lagoon between the reef and the shore. Fringing reefs are directly attached to the shore. Atolls are circular or horseshoe-shaped reefs with a lagoon in the center. However, transitioning reefs are not a recognized type of coral reef.
10.
Coral polyps in coral reefs are held together by
Correct Answer
D. Calcium carbonate
Explanation
Coral polyps in coral reefs are held together by calcium carbonate. Calcium carbonate is the main component of the hard skeleton or structure of corals. It is secreted by the polyps and forms the framework that supports the entire coral reef ecosystem. This compound provides the necessary strength and stability to the coral structure, allowing it to withstand external pressures and environmental conditions. Additionally, calcium carbonate also plays a crucial role in the growth and development of coral reefs, as it provides a substrate for other organisms to attach and grow on.