Water Quality EOG Questions

How do algal blooms affect the health of a water system?

• They photosynthesize and increase the amounts of dissolved oxygen, decreasing the water quality.

• They photosynthesize and decrease the amounts of dissolved oxygen, increasing the water quality.

• They can block sunlight and their decomposition decreases dissolved oxygen in the water, decreasing the water quality.

Which water quality data most likely indicates eutrophication?

• pH level

• turbidity

• temperature

• nutrient level

How do nitrate levels affect the health of a water system?

• As nitrates decrease, there is an increase in plant growth.

• Nitrates cause bacteria to consume large protein molecules.

• Nitrates cause aquatic organisms to die due to oxygen depletion.

• As nitrates increase, there is an increase in dissolved oxygen levels.

The local middle school has a fish pond in the courtyard. The pond water is suffering from eutrophication. Which most likely caused this problem?

• poor filtration

• direct sunlight

• fertilizer runoff

• improper cleaning

Which best explains why a scientist would use nets to capture and count organisms in a river?

• to measure pH

• to measure turbidity

• to measure biodiversity

• to measure temperature

Which factors can have the greatest effect on the health of a river system?

• type of soil and salinity

• nitrate levels and turbidity

• human consumption and pH

• natural disasters and tidal changes

If a large amount of fertilizer enters a lake, which will most likely happen?

• The fish population in the lake will increase.

• The temperature of the lake water will increase.

• The number of fish dying in the lake will increase.

• The available food supply for the fish in the lake will increase.

Why does fertilizer pollution stimulate the growth of algae in a pond?

• Algae are producers and use the fertilizer’s nutrients to rapidly multiply.

• Algae are producers and use the fertilizer’s nutrients during decomposition.

• Algae are parasites and absorb energy from the fertilizers in order to grow.

• Algae are herbivores that feed off of the plants, which grow due to the excess fertilizers.

If a pond is located in an area with significant amounts of air pollution, which health measure would be most directly affected?

• pH

• nitrates

• turbidity

• dissolved oxygen

How are indicator species like a warning system for bodies of water?

• They indicate when food sources are declining.

• Their illness or death indicates pollution in an aquatic ecosystem.

• They indicate when predators are reducing the numbers of a species.

• Their illness or death indicates the body of water is becoming more populated.