Download Grade 8 Science Training Test Answer Key Question 1 Reporting

Grade 8 Science Training Test Answer Key
Question 1
Reporting Category: The Solar System and The Universe
Benchmark: SC.8.8.1 Compare the characteristics of the three main types of rocks
Answer Key: D
The table below shows how four different rocks were formed and gives their composition.
Granite is one kind of intrusive igneous rock.
Which rock described in the table is most likely granite?
A. 1
This answer is not correct. The characteristics of this rock are typical of sedimentary rocks.
Sedimentary rocks form from particles that are compressed (pushed) together over long
periods of time.
B. 2
This answer is not correct. The characteristics of this rock are typical of sedimentary rocks.
Some sedimentary rocks, such as limestone, form when the shells of marine organisms and
calcite are compressed (pushed) together over long periods of time.
C. 3
This answer is not correct. The characteristics of this rock are typical of some igneous rocks.
However, granite is an igneous rock that forms inside Earth’s mantle and not at the surface.
D. 4
This answer is correct. Granite is an igneous rock that forms when magma made of quartz
and other minerals cools and crystallizes below Earth’s surface.
Page 1 of 38
Grade 8 Science Training Test Answer Key
Question 2
Reporting Category: The Solar System and The Universe
Benchmark: SC.8.8.10 Compare the characteristics and movement patterns of the planets in
our solar system
Answer Key: C
Which of the following best describes the inner planets of the solar system?
A. Large gas planets with thick atmospheres
This answer is not correct. This would be a good description for the outer planets, not the
inner planets.
B. Small planets of ice with elliptical orbits
This answer is not correct. All planets have elliptical orbits, but only the dwarf outer planets
are made up largely of ice.
C. Dense, rocky planets with few moons
This answer is correct. The four inner planets are known as the terrestrial planets because
they have solid surfaces and are made from dense minerals and rocks. The inner planets
have fewer moons compared to the outer planets.
D. Barren planets with rings of gas and dust
This answer is not correct. Some of the outer planets have rings of gas and dust, but none of
the inner planets have rings.
Page 2 of 38
Grade 8 Science Training Test Answer Key
Question 3
Reporting Category: The Solar System and The Universe
Benchmark: SC.8.8.8 Describe the composition of objects in the galaxy
Answer Key: B
Many stars in the universe, including the sun, maintain fusion reactions in their cores. Such
stars are known as main sequence stars.
What is the primary fuel of main sequence stars?
A. Uranium
This answer is not correct. Heavy elements like uranium are created when a star goes into its
supernova stage. The supernova stage is after the main sequence stage in the stellar life
cycle.
B. Hydrogen
This answer is correct. A main sequence star, like the sun, is composed of about 73%
hydrogen and 25% helium. In their cores, main sequence stars fuse hydrogen to form helium.
Hydrogen is the fuel of a main sequence star. The main sequence star becomes a red giant
when the amount of hydrogen runs low. Then the star must fuse helium to form carbon. Now
helium is the primary fuel of the star.
C. Oxygen
This answer is not correct. Elements such as carbon, oxygen, and nitrogen make up only 2%
of the elements found in a main sequence star.
D. Carbon
This answer is not correct. Elements such as carbon, oxygen, and nitrogen make up only 2%
of the elements found in a main sequence star.
Page 3 of 38
Grade 8 Science Training Test Answer Key
Question 4
Reporting Category: The Solar System and The Universe
Benchmark: SC.8.8.11 Describe the major components of the universe
A black hole is shown, which is the last stage in a particular type of star’s life cycle.
Place the earlier stages of this star’s life cycle in correct sequence in the blank boxes.
Only three of the star stages shown match this star’s life cycle.
Answer Key:
3 points
For this item, the response correctly:
• places the high-mass main sequence star as the first stage of a star that ends its life as a
black hole
AND
• places the red supergiant as the second stage of a star that ends its life as a black hole
AND
• places the supernova as the last stage of a star before it becomes a black hole.
2 points
For this item, the response correctly:
• places two of the three stages of a star’s life cycle that ends its life as a black hole.
1 point
For this item, the response correctly:
• places one of the three stages of a star’s life cycle that ends its life as a black hole.
0 points
The response provides an incorrect response for all three parts of the item. The response may
have placed the incorrect stage of the star’s life cycle in each of the boxes. The response may
have placed the incorrect and the correct stages of the star’s life cycle in each of the boxes (the
response earns credit if only the correct stage is in the correct box).
Page 4 of 38
Grade 8 Science Training Test Answer Key
Sample Student Answer:
Explanation of Correct Answer:
The high-mass main sequence star will become a red supergiant and then a supernova. The
supernova will then become a black hole, which is the last stage in this particular star’s life.
Page 5 of 38
Grade 8 Science Training Test Answer Key
Question 5
Reporting Category: Biological and Physical Sciences
Benchmark: SC.8.6.3 Identify the characteristics and properties of mechanical and
electromagnetic waves
Answer Key: D
The diagram shows the locations of several students and two mirrors.
•
•
•
Student P is standing in Room 1 looking into Room 2.
Student R is standing in Room 2. There are two mirrors in Room 2.
Student Q and Student S are in Room 3.
Student P can see one student in Mirror M.
Which student can Student P see in Mirror M?
A. Student P
Student P cannot see himself in the mirror because the mirror is tilted away from him.
B. Student Q
Student Q is not visible to Student P because there is a wall between Student Q and the
lower mirror.
C. Student R
Student R is not visible to Student P because there is a wall between them and light would
not go from Student R to either mirror and enter the eyes of Student P because of the
mirrors' locations and tilt.
D. Student S
This answer is correct. Light from Student S goes to the right, hits the lower mirror, goes
up, hits the upper mirror, goes left, and enters Student P's eyes.
Page 6 of 38
Grade 8 Science Training Test Answer Key
Question 6
Reporting Category: Biological & Physical Sciences
Benchmark: SC.8.6.1 Explain the relationship between the color of light and
wavelength within the electromagnetic spectrum
Answer Key: D
Which diagram correctly orders different colors of light according to the value of a
property?
A.
This answer is not correct. The color of light is unrelated to its amplitude.
B.
This answer is not correct. The color of light is unrelated to its amplitude.
C.
This answer is not correct. Red light has a longer wavelength than blue light.
D.
This answer is correct. Red light has a longer wavelength than blue light.
Page 7 of 38
Grade 8 Science Training Test Answer Key
Question 7
Reporting Category: Biological & Physical Sciences
Benchmark: SC.8.7.1 Explain that every object has mass and therefore exerts a
gravitational force on other objects
Answer Key: A
A student studies gravity, using objects that have the same mass.
Which two objects have the greatest gravitational force acting between them?
A.
This answer is correct. If all masses are equal, then the force is greatest
between the closest objects.
B.
This answer is not correct. The gravitational force between two objects decreases
as their separation increases.
C.
This answer is not correct. The gravitational force between two objects decreases
as their separation increases, and shape effects are very small.
D.
This answer is not correct. The gravitational force between two objects decreases
as their separation increases, and shape effects are very small.
Page 8 of 38
Grade 8 Science Training Test Answer Key
Question 8
Reporting Category: The Solar System & The Universe
Benchmark: SC.8.8.10 Compare the characteristics and movement patterns of the
planets in our solar system
Answer Key: C
The atmospheres of which two planets are composed mainly of hydrogen and helium
gases?
A. Mars and Mercury
This answer is not correct. Mars' atmosphere is mostly carbon dioxide.
B. Mars and Saturn
This answer is not correct. Mars' atmosphere is mostly carbon dioxide.
C. Saturn and Neptune
This answer is correct. Saturn and Neptune are both outer planets. Their
atmospheres are composed mostly of hydrogen and helium.
D. Venus and Neptune
This answer is not correct. Venus' atmosphere is mostly carbon dioxide.
Page 9 of 38
Grade 8 Science Training Test Answer Key
Question 9
Reporting Category: The Solar System & The Universe
Benchmark: SC.8.8.2 Illustrate the rock cycle and explain how igneous, metamorphic,
and sedimentary rocks are formed
Answer Key: B
A rock is pushed deep underground in an area where mountain-building is occurring,
and undergoes the following processes.
•
•
•
First, the rock experiences high pressure that causes its minerals to align
themselves in bands.
Second, the rock is pushed further underground and completely melts, then
erupts from a volcano and hardens.
Third, the rock is broken down by wind and water into small particles, which flow
into a river and get compressed into rock.
Which order correctly shows this progression of rock types?
A.
This answer is not correct. The first stage is metamorphic and the second stage is
igneous.
B.
This answer is correct. The rock formed from high pressure is metamorphic, the
rock formed from the volcano is igneous, and the last process causes it to be
sedimentary.
C.
This answer is not correct. The second stage is igneous and the third stage is
sedimentary.
D.
This answer is not correct. The first stage is metamorphic and the third stage is
sedimentary.
Page 10 of 38
Grade 8 Science Training Test Answer Key
Question 10
Reporting Category: The Scientific Process
Benchmark: SC.8.1.2 Communicate the significant components of the experimental
design and results of a scientific investigation
The table shows the data from an investigation on the effect of sunlight on the growth of
plant seedlings.
A. Identify the dependent variable.
B. Explain why Trial 4 is designed incorrectly.
Type your answer in the space provided.
Answer Key:
Correct Dependent Variable:
• The dependent variable is height.
Correct Explanations Why Trial 4 is Designed Incorrectly:
• In Trial 4, the water was changed from previous trials.
• The controlled variable was changed in Trial 4.
• The water was changed in Trial 4.
• The water did not remain the same in Trial 4.
Page 11 of 38
Grade 8 Science Training Test Answer Key
2 points
The answer identifies the dependent variable. The answer correctly explains why trial 4
is designed incorrectly.
1 point
The answer identifies the dependent variable. OR The answer correctly explains why
trial 4 is designed incorrectly.
0 points
The answer does not identify the dependent variable or explain why trial 4 is designed
incorrectly.
Page 12 of 38
Grade 8 Science Training Test Answer Key
Question 11
Reporting Category: The Solar System and the Universe
Benchmark: SC.8.8.3 Describe how the Earth's motions and tilt on its axis affect the seasons
and weather patterns
Answer Key: B
The diagram below shows the tilt of Earth’s axis while Earth is in a certain position in its orbital
path around the sun.
In this diagram, what season is it in the northern hemisphere?
A. Spring
This answer is not correct. As the Earth revolves around the sun, Earth’s axis always points
toward the North Star. Thus, during revolution the North Pole sometimes points toward or
away from the sun. As the Earth travels around the sun and the North Pole is beginning to
point toward the sun, the Northern Hemisphere experiences spring.
B. Summer
This answer is correct. When the North Pole tilts toward the sun, the sun’s rays strike the
Northern Hemisphere more directly. When the sun’s rays strike the Northern Hemisphere
directly, the region is warmer and thus experiences the summer season.
C. Fall
This answer is not correct. As the Earth revolves around the sun, Earth’s axis always points
toward the North Star. Thus, during revolution the North Pole sometimes points toward or
away from the sun. As the Earth travels around the sun and the North Pole is beginning to
point away the sun, the Northern Hemisphere experiences fall.
D. Winter
Page 13 of 38
Grade 8 Science Training Test Answer Key
This answer is not correct. When the North Pole tilts away from the sun, the sun’s rays strike
the Northern Hemisphere less directly. When the sun light is less direct, the region is cooler
and thus experiences the winter season.
Page 14 of 38
Grade 8 Science Training Test Answer Key
Question 12
Reporting Category: The Solar System and The Universe
Benchmark: SC.8.8.5 Explain the concepts of continental drift and plate tectonics
Answer Key: B
Which of the following best describes Earth’s tectonic plates?
A. They move away from each other at the equator.
This answer is not correct. Tectonic plate boundaries occur along Earth’s surface, not just at
the equator. At divergent plate boundaries, tectonic plates move away from each other.
B. They move because of convection currents in the mantle.
This answer is correct. Earth’s core and radioactivity within the mantle heat mantle
material. The heated material rises through the cooler material above it. This rising of
heated material and sinking of cooler material creates convection current within the mantle.
This convection current in the mantle moves tectonic plates above it.
C. They collide at midocean ridges.
This answer is not correct. Midocean ridges are divergent plate boundaries. At divergent
plate boundaries tectonic plates move away from each other.
D. They form at subduction zones.
This answer is not correct. The subduction zone is a region at a plate boundary where one
tectonic plate moves under another tectonic plate. As one tectonic plate moves below the
other, the plate is melted and fluid is released into the mantle above.
Page 15 of 38
Grade 8 Science Training Test Answer Key
Question 13
Reporting Category: Biological and Physical Sciences
Benchmark: SC.8.5.1 Describe how changes in the physical environment affect the survival of
organisms
Answer Key: A
Humans accidentally introduced a new predator into an ecosystem. It began to act as an
invasive species by preying on a native animal.
Which graph shows what would have happened to the invasive species in this new ecosystem?
A.
This answer is correct. The population of the introduced species would start off small and
then increase because of the available food source.
Page 16 of 38
Grade 8 Science Training Test Answer Key
B.
This answer is not correct. The population of the invasive species would have started out
much lower and then increased.
C.
This answer is not correct. The population of the invasive species would start low and then
increase since there was an available food source.
Page 17 of 38
Grade 8 Science Training Test Answer Key
D.
This answer is not correct. The population of the invasive species would have started out
low and then increased.
Page 18 of 38
Grade 8 Science Training Test Answer Key
Question 14
Reporting Category: Biological and Physical Sciences
Benchmark: SC.8.6.2 Explain how seismic waves provide scientists with information about the
structure of Earth's interior
Answer Key: D
A geologist checks her seismometer for activity after an earthquake that occurs on the other
side of Earth. The instrument records P-waves, but not S-waves.
What statement explains why S-waves are not recorded?
A. Seismometers do not record evidence of S-waves.
This answer is not correct. Both S-waves and P-waves register on seismometers.
B. S-waves travel in a different direction than P-waves.
This answer is not correct. Both S-waves and P-waves radiate away from earthquake
epicenters.
C. The earthquake was not strong enough to produce S-waves.
This answer is not correct. All earthquakes produce S-waves.
D. The S-waves were stopped by a liquid interior layer.
This answer is correct. S-waves do not pass through the liquid outer core near the center
of Earth.
Page 19 of 38
Grade 8 Science Training Test Answer Key
Question 15
Reporting Category: The Universe
Benchmark: SC.8.8.9 Explain the predictable motions of the Earth and moon
Earth, the sun, and the orbital path of the moon are shown.
A. Using the “Connect Line” tool, draw two lines between blue dots that show where Earth’s
shadow can cause a total lunar eclipse (an eclipse of the moon).
B. Place the moon at a position in its orbit where a total lunar eclipse can be seen from Earth.
•
•
•
The lines should begin at the blue dots around the sun and end at the blue dots on the right
side of Earth.
Only one line should be drawn from a particular point.
Not all of the blue dots need to have lines between them.
Answer Key:
2 points
For this item, a full-credit response correctly:
• draws two lines that correctly demonstrate how Earth creates a shadow
AND
• places the moon at the correct location in its orbit around the Earth.
1 point
For this item, a full-credit response correctly:
• draws two lines that correctly demonstrate how Earth creates a shadow
OR
• places the moon at the correct location in its orbit around the Earth.
0 points
The response provides an incorrect response for both parts of the item. The response may have
drawn more than two lines. The response may have started and ended both lines at incorrect
positions. The response may have placed the moon in the incorrect position in its orbit around
Earth. The response may have placed more than one moon around the Earth (the response
earns credit if only two lines are drawn and one moon is placed in its correct location in its orbit
around the Earth).
Page 20 of 38
Grade 8 Science Training Test Answer Key
Sample Student Answer:
Explanation of Correct Answer:
A total lunar eclipse (an eclipse of the moon) occurs during at full moon and when the moon
passes through the Earth’s shadow. The two lines indicate the boundaries of the shadow that is
created by Earth. When the moon passes into Earth’s shadow a total lunar eclipse occurs.
Lunar eclipses do not occur every month because the plane of Earth’s orbit around the sun and
the plane of the moon’s orbit around Earth are slightly different.
Page 21 of 38
Grade 8 Science Training Test Answer Key
Question 16
Reporting Category: Science Process
Benchmark: SC.8.1.1 Determine the link(s) between evidence and the conclusion(s) of an
investigation
Answer Key: A
A student comparing the effectiveness of two types of fertilizer plants two bean seeds in
separate pots of equal size. Equal amounts of each type of fertilizer, X and Y, are added to each
pot. The plants are then placed in the sun and watered equal amounts for four weeks. At the
end of each week, the student measures the height of each plant and records her data in the
table shown.
According to the data, what conclusion can be made about the fertilizers?
A. Fertilizer X causes plants to grow at a faster rate than Fertilizer Y.
This answer is correct. The data show that a plant given fertilizer X will grow faster than
one given fertilizer Y.
B. Fertilizer X increases the amount of leaves on the plant.
This answer is not correct. This is a conclusion that cannot be drawn about how fertilizer X
affects leaf production from the data collected.
C. Fertilizer Y causes plants to grow more root hairs than Fertilizer X.
This answer is not correct. The student did not record any data on the number of root hairs
grown by each plant. Therefore, a conclusion cannot be drawn about how the fertilizers
affect root hair growth.
D. Fertilizer Y increases the amount of carbon dioxide plants can take in.
This answer is not correct. The student did not measure how much carbon dioxide was
absorbed by either plant. Therefore, a conclusion cannot be drawn about how either fertilizer
affects carbon dioxide absorption.
Page 22 of 38
Grade 8 Science Training Test Answer Key
Question 17
Reporting Category: Science Process
Benchmark: SC.8.2.1 Describe significant relationships among society, science, and
technology and how one impacts the other.
Answer Key: C
Scientists are able to study all of Earth’s surface using electromagnetic radiation and special
cameras on satellites. This is called remote sensing. Before remote sensing provided this data,
scientists had to hike, drive, or fly airplanes over hard-to-reach areas.
Which is a benefit of using remote sensing instead of older technologies?
A. Scientists are able to draw conclusions without having to analyze data.
This answer is not correct. Conclusions must be based on the analysis of data. Evidence
must support a conclusion even if data was gathered using a new type of technology.
B. Scientists are able to predict earthquakes in distant locations.
This answer is not correct. Earthquakes cannot be reliably predicted, even with satellites.
C. Scientists can analyze more data and spend less time collecting data.
This answer is correct. Satellites allow scientists to use the large amounts of data
gathered by a satellite without spending a lot of time collecting the data in person.
D. Scientists can study layers beneath Earth’s surface more easily.
This answer is not correct. The satellites described above gather information about Earth's
surface.
Page 23 of 38
Grade 8 Science Training Test Answer Key
Question 18
Reporting Category: Science Process
Benchmark: SC.8.2.2 Describe how scale and mathematical models can be used to support
and explain scientific data.
Answer Key: C
For fifty years beginning in 1940, volunteers counted the number of birds in different habitats
around Honolulu for one day each year. The graph shows the data for the annual bird count
during this time.
Which statement best describes the trend in the data from 1940 to 1990?
A. The number of birds seen increased exponentially, doubling about each decade.
This answer is not correct. If the number of birds seen increased exponentially by doubling
each decade, the trend line would show about 50 birds in 1950, 100 birds in 1960, 200 birds
in 1970, etc.
B. The number of birds seen increased exponentially, doubling about every 20 years.
This answer is not correct. If the number of birds seen increased exponentially by doubling
every 20 years, the trend line would show about 50 birds in 1960, 100 in 1980, etc.
C. The number of birds seen increased steadily at a rate of about 30 birds per decade.
This answer is correct. The trend line through the average of the points on the graph
shows a steady growth rate of about 30 birds per decade.
Page 24 of 38
Grade 8 Science Training Test Answer Key
D. The number of birds seen increased steadily at a rate of about 50 birds per decade.
This answer is not correct. If the number of birds increased at a steady growth rate of 50
birds per decade, the trend line would show 50 birds in 1950, 100 birds in 1960, 150 birds in
1970, etc.
Page 25 of 38
Grade 8 Science Training Test Answer Key
Question 19
Reporting Category: The Solar System and The Universe
Benchmark: SC.8.8.4 Explain how the sun is the major source of energy influencing climate
and weather on Earth.
Answer Key: B
The diagram shows a sea breeze. A sea breeze blows from the sea toward the land.
What is the role of the sun in creating a sea breeze?
A. The sun warms the land, creating a condition of higher air pressure that pulls in the cooler
sea air.
This answer is not correct. When the air above the land is warmed, its density decreases.
Therefore, its air pressure becomes lower, not higher.
B. The sun warms the land faster than the sea, causing the air above the land to expand and
rise.
This answer is correct. Because the land surface warms faster than the ocean surface, the
air above the land becomes warmer and less dense, and it rises. This creates an area of low
pressure that draws the cooler sea air inland.
C. The sun warms the sea, creating waves that move the air above the sea surface toward the
land.
This answer is not correct. While solar energy is indirectly involved in the formation of the
ocean’s surface waves, these waves are caused by the wind, not the other way around.
D. The sun warms the sea faster than the land, causing the air above the sea to expand and
spread out.
This answer is not correct. While it is true that heated air will expand, solar energy warms
the land surface faster than the ocean surface.
Page 26 of 38
Grade 8 Science Training Test Answer Key
Question 20
Reporting Category: The Solar System and The Universe
Benchmark: SC.8.8.6 Explain the relationship between density and convection currents in the
ocean and atmosphere.
Answer Key: D
The list shows the procedure that a student used to perform an experiment.
•
•
•
•
Fill a large container with ice water.
Fill a small, open jar with warm water and add two drops of blue food coloring.
Lower the small jar to the bottom of the large container of ice water.
Observe and document what happens.
What phenomenon was this student investigating?
A. Changes in water temperature
This answer is not correct. The procedure did not include the use of a thermometer to
measure water temperatures.
B. Changes in water pressure
This answer is not correct. The procedure did not include the use of a water pressure gauge
to measure water pressure.
C. Conduction between the two jars
This answer is not correct. While conduction occurs between the warm and cold water, and
between the two jars where they touch, the procedure does not include instruction on how to
measure conduction.
D. Convection currents in the water
This answer is correct. Introducing the dyed, warm water into the cold water provides the
conditions necessary for convection to occur: two masses of water with different densities
due to their different temperatures.
Page 27 of 38
Grade 8 Science Training Test Answer Key
Question 21
Reporting Category: Life and Environmental Sciences
Benchmark: SC.8.5.1: Describe how changes in the physical environment affect the survival of
organisms
Answer Key: C
Answer Key (Part II): A; D; E
Part A
The Hawaiian stilt was once a common bird on all the major islands in Hawai‘i. Today, the bird
is on the endangered species list. Some information about the Hawaiian stilt is shown in the
table.
Information About the Hawaiian Stilt
Predators of the
Organisms Consumed by
the Hawaiian Stilt
Habitat and Behavior of the
Hawaiian Stilt
Hawaiian Stilt
•
Non-native species such
as dogs, cats, and
mongooses
•
•
•
Worms
Crabs
Small fishes
A. Aquatic habitats with low
levels of water (about 13
cm)
Which graph represents the results of successful intervention to preserve the Hawaiian stilt
population?
A.
This answer is not correct. Successful human intervention will cause an increase in the
population of the bird, not an increase and then a decrease.
Page 28 of 38
Grade 8 Science Training Test Answer Key
B.
This answer is not correct. Successful human intervention will cause an increase in the
population of the bird, not minor increases and decreases.
C.
This answer is correct. Successful human intervention will cause an increase in the
population of the bird.
D.
This answer is not correct. Successful human intervention will cause an increase in the
population of the bird, not a decrease.
Page 29 of 38
Grade 8 Science Training Test Answer Key
Part B
Select the intervention(s) that could result in the trend of the graph you chose in Part A.
A. Habitat restoration
This answer is correct. This is a conservation effort to protect the species to help their
population increase.
B. Introduction of invasive species
This answer is not correct. This is not a conservation effort and will harm the species,
causing a decrease in the population due to competition and predation.
C. Land use development
This answer is not correct. This is not a conservation effort and will harm the habitats of
the species, causing a decrease in the population.
D. Pollution control
This answer is correct. This is a conservation effort to protect the species to help their
population increase.
E. Wetland conservation
This answer is correct. This is a conservation effort to protect the species to help their
population increase.
Page 30 of 38
Grade 8 Science Training Test Answer Key
Question 22
Reporting Category: Earth and Space Science
Benchmark: SC.8.8.8: Describe the composition of objects in the galaxy
A student is writing a report that describes the composition of objects in space. The passage
contains three highlighted words that may be incorrect. Click on each highlighted word to select
the correct word.
For this item, a full-credit response includes
•
“Comets” selected in first choice (1 point)
AND
•
“Stars” selected in second choice (1 point)
AND
•
“star” selected in fourth choice (1 point)
Page 31 of 38
Grade 8 Science Training Test Answer Key
Question 23
Reporting Category: Physical Science
Benchmark: SC.8.8.8: Describe the composition of objects in the galaxy
Select the frequency and wavelength of each color of light.
Row
Column
1
a
2
c
3
b
4
b
5
c
6
a
Page 32 of 38
Grade 8 Science Training Test Answer Key
Question 24
Reporting Category: Earth and Space Science
Benchmark: SC.8.8.6: Explain the relationship between density and convection currents in the
ocean and atmosphere
Students create the classroom model shown in the diagram. A cup of dyed ice water is attached
to the inside of a tank filled with water at 30° C. The ice water flows into the tank through a small
hole in the bottom of the cup, as shown.
Select the two large systems the students can investigate using this model.
A. Density Currents
This answer is correct. The investigation allows students to model density currents as
colder, denser water sinks, warms, and then rises as less dense water.
B. Global wind current patterns
This answer is correct. Because air with different densities and temperatures produces
convection currents in the atmosphere, the model can be used to investigate global wind
current patterns.
Page 33 of 38
Grade 8 Science Training Test Answer Key
C. Ocean water biomes
This answer is not correct. The investigation models convection currents produced by
differing densities of water, not ecosystems within the ocean.
D. Temperature profile of ocean water
This answer is not correct. While the investigation deals with different temperatures. it
does not deal with the temperature striations in ocean water.
E. Upwelling of water currents
This answer is not correct. The investigation models convection currents produced by
differing densities of water, not the replacement of surface water pushed away by wind
with water from beneath the surface.
Page 34 of 38
Grade 8 Science Training Test Answer Key
Question 25
Reporting Category: Physical Science
Benchmark: SC.8.6.1: Explain the relationship between the color of light and wavelength within
the electromagnetic spectrum
A table lists different colors of light.
Complete the table by ranking these different colors of light by wavelength, from longest
wavelength (1) to shortest (6).
Exemplar:
5
Blue
4
Green
2
Orange
1
Red
6
Violet
3
Yellow
Page 35 of 38
Grade 8 Science Training Test Answer Key
Question 26
Reporting Category: Physical Science
Benchmark: SC.8.6.2: Explain how seismic waves provide scientists with information about the
structure of Earth's interior
An article describing what people learn from Earthquake waves is shown.
Select the sentence that describes how refraction works.
Learning about Earth’s interior from Earthquakes
Earthquake p-waves and s-waves travel through Earth. All over the planet, scientists record and
measure earthquake waves with seismographs when they arrive. Scientists have noticed that pwaves go through the center of Earth at a faster speed than they do in surface rock. From that,
scientists infer that the middle of the Earth is denser than the surface. Also, p-waves and s-waves
seem to change direction slightly at certain depths within Earth. When a wave goes from one
density of material to another, it can bend. Scientists infer from this that the places where the
waves changed direction are the boundaries between different Earth layers.
Exemplar:
•
Students select “When a wave goes from one density of material to another, it can bend.”
and only that sentence.
Page 36 of 38
Grade 8 Science Training Test Answer Key
Question 27
Reporting Category: Earth and Space Science
Benchmark: SC.8.8.9 Explain the predictable motions of the Earth and moon
Students in Hawaii are tracking the daily location of the sun and moon twice a week to determine
patterns in their movement and appearance.
Design and conduct an investigation using the students’ observations.
Select the two statements about the expected observations on Monday of Week 5 that are
supported by the simulation results.
A. Sunrise will occur at 5:00 a.m.
Page 37 of 38
Grade 8 Science Training Test Answer Key
This answer is not correct. The sunrise pattern shows that the sun rises later each day,
so one would not expect the sun to rise earlier than any sunrise given in the simulation.
B. The lunar phase will be the New Moon.
This answer is correct. The moon will begin its lunar cycle again during Week 5,
starting with the New Moon also seen in Week 1.
C. The sun and moon will rise around 6:05 a.m.
This answer is correct. The moon and sun rise around the same time during Week 5,
repeating the beginning of the cycle that began in Week 1.
D. Sunset will occur at the same time as the moon rises.
This answer is not correct. The sunset occurred at the same time that the moon rose
during Week 3, when the lunar phase was the Full Moon. In the lunar cycle shown in the
simulation, this phenomenon will be seen again during Week 7, not during Week 5.
E. The Full Moon will rise at 12:30 p.m. and set at 12:30 a.m.
This answer is not correct. The moon rise and set times are incorrect. The Full Moon
rises around sunset, roughly 6:00 p.m., and sets at sunrise, roughly 6:00 a.m.
Additionally, Week 5 will see a New Moon, not a Full Moon.
F. The moon will be below the horizon during daylight hours.
This answer is not correct. During Week 1, the moon was above the horizon during
daylight hours. This phenomenon repeats during Week 5, so the moon is above, not
below the horizon during the day.
Page 38 of 38