A Competition

• A

• B

• C

• D

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-2

A group of scientists studied some trees in a pine forest. In the densely forested areas, the trees were within 1 m of each other. The scientists observed that these trees had dead branches near the ground. They measured the height above the ground at which the first living branches were found on different-sized trees in the forest. Then they repeated this procedure on the same kind of trees in an open meadow. This graph summarizes the scientists’ data.

Which inference is best supported by these data?

• Pine trees in a dense forest can grow taller than pine trees in an open meadow.

• Pine trees in a dense forest compete for sunlight with the surrounding trees.

• Pine trees in a dense forest are part of a less-complex food web than pine trees in an open meadow.

• Pine trees in a dense forest have more living branches than pine trees in an open meadow.

Tags

NGSS.MS-LS1-5

NGSS.MS-LS2-1

NGSS.MS-LS2-4

A scientist added bacteria and a nutrient medium that could support the growth of the bacteria to a sterilized petri dish. No other materials were added. The graph models growth of the bacteria over time. Which of these most likely explains why the bacterial population stopped growing?

• The bacteria competed for nutrients and died after all the nutrients were consumed.

• The bacteria did not reproduce in the system, and eventually each individual died at the end of its life cycle.

• The bacteria mutated from photosynthetic to carnivorous organisms and consumed one another until all the individuals were dead.

• The bacteria became diseased and were unable to survive in the closed system.

Tags

NGSS.MS-LS1-5

NGSS.MS-LS2-1

After researching the diets of several birds inhabiting a nearby pond, a student goes on a field investigation to observe the feeding habits of the birds. The student records information from research and observations in the table. The student observes a great blue heron catching fish near the edge of the pond. Based on the information the student collected, which bird will compete with the great blue heron for the same hunting spots and similar prey?

• The mallard, because it hunts for fish while wading near the edge of the pond

• The pied-billed grebe, because it dives in open water to get crayfish on the bottom of the pond

• The great egret, because it hunts in water near the edge of the pond for fish and other prey

• None of these

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-2

The graph below shows the range of water conditions preferred by three species of fish in an Ozark stream.

Water with which of these conditions would cause the most competition for resources among all three species of fish?

• Very cold, very clear, and very fast

• Very warm, very clear, and very slow

• Mild temperatures, some suspended particles, flows very fast

• Mild temperatures, some suspended particles, flows at a medium speed

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-4

Barnacles are marine organisms that live attached to surfaces as adults. A scientist studies two barnacle species that live on rocks on a coast in Scotland. In some rocky areas Species A is found alone. In other rocky areas Species B is found alone. In still other rocky areas both species are found together. The diagram below shows the two barnacle species on rocks in their habitats.

If Species B were removed from the rocky areas it shares with Species A, Species A would most likely inhabit —

• Zone I only

• Zones I and II only

• Zone III only

• Zones I, II, and III

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-2

NGSS.MS-LS2-4

A scientist named Joseph Connell studied two species of barnacles on the shore of a Scottish island. In the area between the average tide and the neap high tide, he found that the population of Species A was smaller than that of Species B. He removed Species B from one area but left both Species A and B in a similar area. The graph below shows the results of this study. Based on these data, which hypothesis was Connell most likely testing?

• The populations of both species of barnacles increase more in warm water than in cool water.

• Barnacles grow larger when they are isolated from other species.

• The two species of barnacles compete with each other for resources.

• The two species of barnacles are closely related to each other.

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-4

Which organisms in the food web shown above compete for the same food source in this environment?

• Grasshoppers and snakes

• Hawks and frogs

• Frogs and snakes

• Decomposers and grasses

Tags

NGSS.MS-LS2-1

This diagram shows the variety of organisms that live in different tide zones. Mussels are common organisms that compete for space in intertidal (middle) tide zones. If all of the mussels were removed from zone A, which organisms would likely compete for the space in Zone A?

• Periwinkle and Limpets

• Sea lettuce and Chiton

• Sea urchins and Hermit crabs

• Rock louse and Periwinkle

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-4

In a science competition, students are asked to identify the gas produced when hydrochloric acid reacts with zinc. What is the gas?

• Oxygen

• Hydrogen

• Carbon Dioxide

• Nitrogen

Tags

NGSS.MS-PS1-2