DIA 7 Review

In a forest ecosystem, rabbits are the main food source for a population of foxes. Over the course of several months, a disease spreads through the rabbit population, significantly reducing their numbers. What will most likely happen to the fox population over time as a result of this change?

• The fox population will gradually decline due to a lack of food

• The foxes will quickly switch to eating only plants

• The fox population will increase as they compete for territory

• The foxes will not be affected because they live longer

Answer explanation

As the rabbit population decreases due to disease, the primary food source for the foxes diminishes. Consequently, the fox population will likely decline over time due to a lack of food.

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-4

A researcher is studying a relationship between bacteria, ticks, and deer in a forest. The bacteria live inside the ticks, but when the ticks feed on deer, the deer often get sick. Which type of relationship is seen between the bacteria and ticks, and between the ticks and deer?

• Commensalism between bacteria and ticks; parasitism on deer

• Parasitism between bacteria and ticks; mutualism on deer

• Mutualism between ticks and deer; parasitism on bacteria

• Commensalism between all three organisms

Answer explanation

The bacteria and ticks have a mutualistic relationship, as the bacteria help the ticks survive. In contrast, ticks feed on deer, causing them harm, which is a parasitic relationship.

Tags

NGSS.MS-LS2-2

A biologist observes a dog scratching constantly and finds small insects on its skin feeding on its blood. Over time, the dog begins to lose weight and fur in the affected areas. What kind of interaction is occurring between the dog and the insects?

• Parasitism

• Commensalism

• Mutualism

• Competition

Answer explanation

The interaction between the dog and the insects is parasitism, as the insects feed on the dog's blood, harming it by causing weight loss and fur loss, while benefiting themselves.

In a coral reef, a tiny fish is seen cleaning parasites off the scales of a larger fish. The large fish allows the cleaner fish to stay around and doesn’t eat it. Both fish seem to benefit. What type of relationship is this?

• Mutualism

• Parasitism

• Competition

• Commensalism

Answer explanation

The relationship between the tiny fish and the larger fish is mutualism, as both species benefit: the cleaner fish gets food by removing parasites, while the larger fish enjoys better health and hygiene.

A researcher notices that barnacles attach to the shells of sea turtles. The barnacles get carried around the ocean, gaining access to food and oxygen-rich water, but the turtles aren’t affected. What kind of symbiotic relationship is this an example of?

• Parasitism

• Mutualism

• Commensalism

• Competition

Answer explanation

This scenario illustrates commensalism, where barnacles benefit by gaining food and mobility from the turtle without harming it. The turtles remain unaffected, highlighting the one-sided benefit characteristic of commensalism.

A town decides to replace a natural prairie with a shopping center and increases road traffic. Within months, air quality begins to drop and local temperatures rise. Which human activity is most responsible for this environmental impact?

• Burning more fossil fuels due to increased traffic

• Using solar panels on the building

• Planting trees around the parking lot

• Recycling trash from the stores

Answer explanation

The increase in road traffic from the shopping center leads to burning more fossil fuels, which directly contributes to air quality decline and rising temperatures, making it the primary human activity responsible for the environmental impact.

Tags

NGSS.MS-ESS3-4

NGSS.MS-LS2-4

A city launches a campaign to get more people to use buses, trains, and bicycles instead of driving. After several months, scientists record a noticeable drop in carbon dioxide in the atmosphere. Which statement best explains how the campaign helped the environment?

• Public transportation reduces emissions from individual vehicles

• Buses require more gasoline than cars

• Bicycles create more pollution during manufacturing

• The campaign increased the need for fossil fuels

Answer explanation

The campaign encouraged the use of public transportation, which reduces the number of individual vehicles on the road, leading to lower carbon dioxide emissions and a positive impact on the environment.

Farmers in a region begin applying more fertilizers and pesticides than recommended to speed up crop growth. Soon after, nearby rivers start showing signs of algae overgrowth and fish deaths. What caused this environmental harm?

• Overuse of chemical pesticides and fertilizers

• Crop rotation

• Installing irrigation systems

• Growing organic crops

Answer explanation

The overuse of chemical pesticides and fertilizers leads to nutrient runoff into rivers, causing algae overgrowth and fish deaths. This demonstrates the negative impact of excessive chemical use on the environment.

Tags

NGSS.MS-ESS3-4

NGSS.MS-LS2-4

A developer clears out a forested hillside to build luxury homes. After heavy rainstorms, nearby neighborhoods experience mudslides and cloudy river water. What environmental effect most likely resulted from cutting down the forest?

• An increase in soil erosion

• A decrease in air pollution.

• A decrease in water runoff.

• An increase in biodiversity.

Answer explanation

Cutting down the forest removed tree roots that stabilize the soil. Without this support, soil erosion increased, leading to mudslides and cloudy river water in nearby neighborhoods after heavy rain.

Tags

NGSS.MS-ESS3-4

NGSS.MS-LS2-4

According to the food web, which trophic level is the mouse?

• Producer

• Primary consumer

• Secondary consumer

• Tertiary consumer

Answer explanation

The mouse is classified as a secondary consumer because it primarily feeds on primary consumers, such as plants or seeds, placing it above them in the food web hierarchy.

Tags

NGSS.MS-LS2-3