7th Grade: Unit 1 Quiz Answers - Middle School Science

Lesson 1 Quiz

1. D	4. D
2. C	5. C
3. C

A is incorrect because the geosphere is the rocky, solid part of Earth.

B is incorrect because the cryosphere is Earth’s water in its solid (frozen) form.

C is incorrect because the atmosphere is the mixture of gases that surrounds Earth.

D is correct because the hydrosphere is the liquid water on Earth, which includes the water in wetlands.

A is incorrect because oxygen is not part of the biosphere, which consists only of living things.

B is incorrect because the oxygen that organisms breathe is not part of the geosphere.

C is correct because the oxygen that organisms breathe is part of the atmosphere that surrounds Earth.

D is incorrect because the oxygen that birds breathe is not part of the hydrosphere.

A is incorrect because rain is part of the hydrosphere.

B is incorrect because lakes are part of the hydrosphere.

C is correct because permafrost and icebergs are solid forms of water, which make up the cryosphere.

D is incorrect because rainfall is part of the hydrosphere.

A is incorrect because the interaction of the geosphere (rocky Earth and its layers) and bio-sphere (living things) do not cause waves and currents to form.

B is incorrect because the interaction of the biosphere (living things) and hydrosphere (liquid water) do not cause waves and currents to form.

C is incorrect because the interaction of the cryosphere (frozen water) and atmosphere (gases surrounding Earth) do not cause waves and currents to form.

D is correct because the sun’s energy in the atmosphere (gases surrounding Earth) creates wind, and the interaction of wind and the hydrosphere (liquid water) produces waves and surface currents.

A is incorrect because mountains are not a source of energy for the whole of Earth’s biosphere.

B is incorrect because trees are part of Earth’s living things and are a source of energy for some things but are not their own source of energy.

C is correct because all of Earth’s living things derive their energy, ultimately, from the sun.

D is incorrect because storms and lightning do not provide energy to living things.

Lesson 2 Quiz

1. A	4. A
2. B	5. C
3. D

A is correct because weathering is the process by which rocks are broken down by physical and chemical means.

B is incorrect because erosion is the process that moves rocks.

C is incorrect because weathering breaks down rocks.

D is incorrect because weathering breaks down rocks, but does not change them into a different type of rock.

A is incorrect because pebble 1 had more abrasion, so it was more easily worn away and is softer.

B is correct because pebble 2 did not wear away as easily as pebble 1, so it is harder.

C is incorrect because the rate of abrasion does not depend on the chemical properties of the rock.

D is incorrect because the rate of abrasion is a physical process, not a chemical process.

A is incorrect because chemical weathering does not lead to the formation of crystals.

B is incorrect because rocks may react with acids but do not usually produce acids when they are weathered.

C is incorrect because chemical weathering wears away the rock, and stronger rock would be more difficult to wear away.

D is correct because the chemical composition of
the rock changes, and the substances usually crumble more easily than the original rock.

A is correct because plant roots and ice wedging can cause cracks in rocks to grow over time.

B is incorrect because wind abrasion does not cause cracks in rocks to grow.

C is incorrect because animal burrowing does not cause cracks in rocks to grow.

D is incorrect because animal burrowing and wind abrasion do not widen cracks in rocks.

A is incorrect because acids are not an agent of physical weathering.

B is incorrect because acids would not decrease physical actions that lead to weathering.

C is correct because acids are agents of chemical weathering, and the decaying leaves will make the soil more acidic.

D is incorrect because chemical weathering happens more quickly in more acidic conditions.

Lesson 3 Quiz

1. A	4. D
2. D	5. C
3. B

A is correct because erosion is defined as the movement of soil or sediment from one place to another.

B is incorrect because the term discharge refers to the amount of water in a water body.

C is incorrect because deposition describes the soil being laid down, and the correct term for the movement of soil from one place to another is erosion.

D is incorrect because weathering is defined as the breakdown of rocks.

A is incorrect because not all liquid water is groundwater, but only water below Earth’s surface.

B is incorrect because groundwater is defined as water below Earth’s surface and can be moving.

C is incorrect because groundwater is defined as water below Earth’s surface, not water on Earth’s surface.

D is correct because groundwater is defined as water below Earth’s surface (collected and stored underground).

A is incorrect because deep valleys in the mountains are commonly caused by streams rather than earthquakes.

B is correct because as streams flow through the mountains, the running water causes erosion and a deep valley forms.

C is incorrect because deep valleys in the mountains are commonly caused by streams, not rock landslides.

D is incorrect because the most likely cause is erosion by water, not erosion by wind.

A is incorrect because the appearance of coarse sand and pebbles in the sediment indicate a higher rate of erosion after a storm.

B is incorrect because the sediment flowing in the stream containing fine sand indicates erosion even before a storm.

C is incorrect because the appearance of coarse sand and pebbles in the sediment indicate a higher rate of erosion after a storm.

D is correct because the particle load, or size of particles, is greater after a storm, and large par-ticles cause more erosion than small particles.

A is incorrect because an alluvial fan forms because of a change in slope and speed, not from an increase in water volume.

B is incorrect because sediment falls out because the land is flatter, not because the land is steeper.

C is correct because as the stream entered an area with a lower slope, it spread out and moved slower, and the slower speed caused sediment to drop out.

D is incorrect because an alluvial fan forms as a stream spreads out and becomes wider.

Lesson 4 Quiz

1. D	4. B
2. A	5. B
3. B

A is incorrect because a dune is an example of deposition by wind, not mass movement caused by gravity.

B is incorrect because loess is an example of deposition by wind, not mass movement caused by gravity.

C is incorrect because a glacier is an example of erosion and deposition by ice, not mass move-ment caused by gravity.

D is correct because a mudslide is an example of mass movement caused by gravity.

A is correct because loess is rich in minerals and forms good soil for growing crops.

B is incorrect because loess does not contain bits of rock; it is made of layers of fine-grained sediment.

C is incorrect because loess does erode easily, which is not a property that makes it valuable.

D is incorrect because loess is not difficult to find.

A is incorrect because the sediment does not play a role in whether the lake will dry up; the sediment is necessary to form a shoreline to contain the water.

B is correct because without the sediment, the water would not stay contained.

C is incorrect because although vegetation needs sediment in order to grow, vegetation is not necessary for the formation of the lake.

D is incorrect because sediment does not play a role in ice melting.

A is incorrect because although it must be below freezing for a glacier to form, there must also be lots of snow, so it will not usually be dry.

B is correct because for a glacier to form it must be cold and more snow must fall than melts, so the snow can be compacted into a glacier.

C is incorrect because although there must be a fair amount of precipitation, it must be cold, not mild, for a glacier to form.

D is incorrect because although it must be below freezing for a glacier to form, more snow must fall than melts.

A is incorrect because the lake bed was dry, so ice was not a factor in forming the dunes; rather, the sand was blown from the lake bed by wind.

B is correct because wind is the agent responsible for the formation of the sand dunes, with the sand at the bottom of the dry lake bed.

C is incorrect because the lake bed was dry, so water could not have formed the dunes.

D is incorrect because gravity would pull sediment and sand toward Earth, and because the sand dunes rise above the lake bed, they were most likely formed by wind.

Lesson 5 Quiz

1. A	4. A
2. C	5. C
3. D

A is correct because soil formation begins with rock breaking up into small pieces.

B is incorrect because bedrock is solid rock that lies below layers of soil.

C is incorrect because ice wedging involves water freezing and thawing in cracks of rock.

D is incorrect because rock is an inorganic material. Organic material is made of once-living material.

A is incorrect because the water that seeps into the soil will cause chemical weathering.

B is incorrect because erosion does not aid in soil formation.

C is correct because the mixing action of larger burrowing animals helps the function of de-composers and the aeration of the soil.

D is incorrect because exfoliation is not the process by which the tortoise breaks up rocks.

A is incorrect because although larger animals can affect the physical characteristics of soil by digging burrows, microorganisms are too small to dig burrows.

B is incorrect because atmospheric forces, not microorganisms, are the agents of weathering on Earth’s surface.

C is incorrect because pore spaces and moisture describe physical characteristics of soil; also, microorganisms are too small to have much effect on the presence of pore spaces in soil.

D is correct because microorganisms decompose dead organisms and return nutrients to the soil, which affects the soil’s chemistry.

A is correct because the organic and chemical nutrients that plants need to grow are most abun-dant in horizon A

B is incorrect because rock fragments have little to do with soil fertility.

C is incorrect because soil fertility is the soil’s ability to hold and supply nutrients to plants, not the ability to hold or supply water.

D is incorrect because the solid rock in horizon D contains little organic material, so does not contribute to soil fertility.

A is incorrect because pore spaces are spaces between soil particles through which water and air can move.

B is incorrect because humus is dark, organic material, whereas weathered sediment is inorganic material.

C is correct because humus is dark, organic material formed in soil from the decayed remains of plants and animals.

D is incorrect because soil is a loose mixture of rock fragments, organic material, water, and air that can support the growth of vegetation.