What is the main component of water?

• Oxygen and Carbon

• Hydrogen and Oxygen

• Hydrogen and Nitrogen

• Hydrogen and Helium

What percentage of Earth's water is fresh water?

• 50%

• 10%

• 3%

• 1%

What process in the water cycle leads to cloud formation?

• Condensation

• Evaporation

• Transpiration

• Precipitation

What is the pH value of pure water?

• 9

• 8

• 7

• 6

Which gas is primarily responsible for photosynthesis in aquatic environments?

• Hydrogen

• Carbon Dioxide

• Oxygen

• Nitrogen

What is the main source of oxygen in water?

• Algae

• Coral

• Phytoplankton

• Fish

What happens to the density of water as it freezes?

• It increases

• It decreases

• It stays the same

• It evaporates

What is the role of solar radiation in aquatic environments?

• It cools the water

• It helps plants grow

• It creates waves

• It makes water salty

Which of the following is a physiological adaptation of deep-sea fish?

• Large eyes

• Bright colors

• Small fins

• Flat bodies

What is the effect of increased CO2 levels in water?

• Decreased temperature

• Acidification

• Increased oxygen levels

• Increased salinity