7th Science Midterm

Examine the diagram provided. Based on the diagram, which organisms compete for food resources?

Answer explanation

Mountain lions and coyotes compete for food resources because they both eat antelopes. Antelopes and squirrels compete as well because they both eat grass.

Tags

NGSS.MS-LS2-1

What 2 types of factors comprise an ecosystem?

Answer explanation

An ecosystem consists of biotic factors, or organisms composed of cells, and abiotic (nonliving) factors such as temperature, sunlight, and water.

Tags

NGSS.MS-LS2-4

NGSS.MS-LS2-3

Eagles and grizzly bears live together in the same habitat. There will be competition between the eagles and the grizzly bears only if which of the following is true?

• Pesticides in the fish population affect eagles’ eggs and decrease
        their population.

• Both grizzly bears and eagles feed on the same species of
        salmon.
  

• Grizzly bears hibernate during the winter while eagles remain
        active.

• Laws prevent humans from being able to hunt eagles or grizzly
        bears.

Tags

NGSS.MS-LS2-2

NGSS.MS-LS2-1

In a forest habitat, how are the populations of rabbits and foxes dependent on each other?

Answer explanation

Foxes prey on rabbits, so they are dependent on them for food. If foxes keep the rabbit population stable, then there is enough food for the surviving rabbits in an ecosystem.

Tags

NGSS.MS-LS2-4

NGSS.MS-LS2-2

The milkweed plant serves an important role in the life cycle of the monarch butterfly. Adult monarchs lay their eggs in milkweed, and then caterpillars eat that same plant during their development. Based on the relationship between monarchs and milkweed, which of the following trends would be predicted when looking at data on the populations of these two organisms?

• Population of monarch butterflies should remain constant when milkweed population decreases.

• Population of milkweed should remain constant when monarch butterfly population increases.

• Population decrease in monarch butterflies should follow population decrease in milkweed.

• Population increase in monarch butterflies should follow population decrease in milkweed.

Tags

NGSS.MS-LS2-4

NGSS.MS-LS2-2

NGSS.MS-LS2-1

Explain the importance of photosynthesis.

Answer explanation

Photosynthesis is important b/c it allows plants to make energy from the Sun. The plants use this energy for life functions. Animals eat the plants and use the energy that is inside the plants for their life functions.

Tags

NGSS.MS-LS2-3

NGSS.MS-LS1-6

Students are observing an aquatic plant. They understand that the bubbles they see rising from the cut stem of the plant are the gasses produced during photosynthesis. Which of the following observations provides the best evidence that light is the source of energy for photosynthesis?

• The frequency of bubbling increases in bright light and slows to a stop in darkness.

• The bubbles always rise to the surface of the water, moving towards the light.

• Plants observed in artificial or in natural light were both seen to produce bubbles.

• The orientation of the light seems to have no effect on the production of bubbles.

Tags

NGSS.MS-LS1-6

What happens during cellular respiration?

Answer explanation

The bonds of food molecules and oxygen molecules are broken and new compounds are formed that can transport energy to muscles. Cellular respiration also releases the energy needed to maintain body temperature despite ongoing energy transfer to the surrounding environment.

Tags

NGSS.MS-LS1-7

How does the conservation of matter relate to the process
of digestion?

Answer explanation

The law of conservation of matter says that matter is neither created nor destroyed. This relates to digestion because when large, complex molecules are broken down, the number of atoms of each element still remains the same. For example, complex carbohydrates will break down into simple sugars (glucose) and other smaller molecules.

Tags

NGSS.MS-LS1-7

NGSS.MS-PS1-5

Students are using beads of different colors to represent the
      molecules in food. The beads can be connected in chains in
      different arrangements to represent different kinds of
      molecules. What is the best way for the students to use 
      the beads to represent the process of photosynthesis and  
      cellular respiration that allow plants and animals to get the
      energy they need?

• Combine the beads in chains, take them apart, and then put them together in new chains.

• Connect different combinations of beads into chains so that no two are alike.

• Connect all the beads together into the longest chain that can be made.

• Take apart all chains and separate the beads by color into groups.

Tags

NGSS.MS-LS2-3

NGSS.MS-LS1-6

NGSS.MS-LS1-7