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Worksheets8th Grade Science FAST Review
Total questions: 45
Worksheet time: 11hrs 15mins
Janice is learning about compounds.
Which of the following best describes a compound?
a substance made up purely of one element
a group of substances that are either acids or bases
a group of substances that can be separated by a physical change
a substance made up of two or more elements that are chemically combined
Scientific theories are developed over time in all areas of science. Which statement best describes scientific theories?
They are based on scientific laws that came first.
They are pieces of scientific evidence that support a hypothesis.
They are explanations of scientific events that may change based on continuous research.
They are predictions of events that usually remain constant because scientific ideas rarely change.
Many interactions occur between the biosphere and the atmosphere. One of these interactions results in changes in atmospheric carbon dioxide (CO2) levels. The graph below shows these changes over a two-year period.
Which of the following changes in the biosphere most likely caused these changes in the atmospheric CO2 levels?
Streams froze in the winter and melted in the spring.
Plants grew leaves in the spring and lost leaves in the fall.
Offspring were born in the summer and matured in the fall.
Soil dried out in the summer and absorbed moisture in the winter.
Jordan adds some soil and plants to a large glass jar to build a terrarium. He waters the plants and then adds two snails, two crickets, and an earthworm to the jar. Jordan then places the lid tightly on the jar and sets it on a sunny windowsill. Based on the law of conservation of mass, which of the following is expected to occur inside Jordan’s terrarium?
The mass will increase as the plants grow and decrease when the snails eat the plants.
The mass will increase as the earthworm digests the soil.
The mass will decrease when the crickets die.
The mass will neither increase nor decrease.
Human body systems interact to keep blood pressure within a normal range. The diagram below represents this interaction.
Which of the following best describes what is occurring in part X of the diagram?
Respiration remains high as other body systems work with the circulatory system.
Blood pressure is regulated as the circulatory system shuts down other body systems.
Blood pressure remains high as the circulatory system shuts down other body systems.
Homeostasis is maintained as the other body systems work with the circulatory system.
The table below shows the range of frequencies, in Hertz (Hz), for part of the electromagnetic spectrum.
Which of the following types of radiation has the longest wavelength?
Infrared
Ultraviolet
X-rays
Gamma rays
An astronomer observes a sunspot. Which of the following describes this feature of the Sun?
a location where heat rises to the Sun’s surface
a location that produces most of the Sun’s heat energy
a location that is cooler than other parts of the Sun’s surface
a location where energy and matter leave the Sun’s atmosphere
Ricky wants to finish constructing a chart that helps classify two organisms. The chart is shown below.
Accurately answering which question would best help distinguish these organisms as members of the animal kingdom rather than the plant or fungi kingdom?
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Atoms are made up of subatomic particles, including neutrons. Which of the following describes a neutron?
has a greater volume than the electron cloud
has more mass than the nucleus
has no charge
has no mass
Two groups of students hypothesized that rocks on Earth’s surface are damaged by acid rain.
● Group X tested the hypothesis by examining properties of some rocks and pouring a weak acid, vinegar, on each of the rocks.
● Group Y later repeated the same procedure with a different group of rocks.
The rocks used for the investigations and the results from each student group are shown below.
Which of the following best describes an advantage Group X has over Group Y in supporting the hypothesis?
Group X tested the rocks before Group Y did.
Group X tested more rocks that are smoother
Group X tested rocks with a greater average mass.
Group X tested a greater variety of rocks than Group Y did.
Mandy applies the brakes on her bicycle and stops quickly to avoid hitting a basketball that bounces into the street. Which of the following best explains what happens to the bicycle’s kinetic energy?
It increases because the tires make a screeching noise.
It is destroyed because Mandy stops the bicycle quickly.
It remains the same because Mandy is the source of energy.
It is transformed to heat because the tires are slowed by friction.
The diagram shows two hypotheses for the same process that occurs beneath Earth’s surface.
Which of the following processes is represented by these hypotheses?
convection current movement in Earth’s mantle
plate movements in Earth’s outer core
layer separation in Earth’s inner core
rock formation in Earth’s lithosphere
North Atlantic right whales live in the ocean near the east coast of the United States and Canada. Fewer than 500 of these whales exist. Which of the following would contribute to the extinction of the North Atlantic right whales?
Species that compete with right whales move to new habitats.
Humans develop breeding programs for right whales in aquariums.
The environment changes faster than right whale populations can adapt.
New technologies prevent right whales from being caught in fishing gear.
The diagram below identifies three structures found in the human body.
Which level of organization describes each of these three structures?
cell
organ
organism
tissue
A space probe lands on a planet that has half the pull of gravity as Earth.
What effect does this have on the space probe’s weight and mass?
Its weight is reduced to half its weight on Earth, and its mass remains the same as on Earth.
Its weight remains the same as on Earth, and its mass is reduced to half its mass on Earth.
Both its weight and mass are half of what they are on Earth.
Both its weight and mass remain the same as on Earth.
Cells experience similar processes. One of these processes involves controlling cellular wastes. Why do cells undergo processes that control cellular wastes?
All cells must release cellular wastes to maintain homeostasis.
Plant cells eliminate cellular wastes to regulate the rate of cell
reproduction.
Animal cells extract energy from cellular wastes to perform cellular functions.
All cells must release cellular wastes to provide a means of maintaining cell size.
Nancy observes the Moon from the same location outside each night for one week. She notices that when it first appears each night, the Moon is a little farther east than it was the night before. Which of the following is one explanation for her observation?
The Moon’s speed of rotation changes as it revolves around Earth.
The Moon revolves around Earth as Earth revolves around the Sun.
The Moon and Earth take the same amount of time to complete one rotation.
The Moon completes one rotation each time Earth completes one revolution.
Brittany is investigating plant growth. She completes the following activities in class.
Which statement best describes why activity 1 is an experiment and activity 2 is an investigation?
Only activity 1 has a control and variables
Only activity 1 requires the adding of fertilizer.
Activity 1 requires more trials than activity 2 does.
Activity 1 takes more time to set up than activity 2 does.
At a mid-ocean ridge, plates are pulled apart. Fracturing in the sea floor allows magma to move up from the mantle. The diagram below shows two plates that are moving apart
Which process in the rock cycle does this diagram best represent?
chemical weathering of rocks
erosion of sedimentary rocks
compaction of melted rock
formation of igneous rock
Students compared the solubility of sodium chloride (NaCl)
and potassium chloride (KCl) in water at different temperatures. They recorded their results as mass, in grams (g), dissolved in 100 milliliters (mL) of water at different temperatures, in degrees Celsius (°C), as shown in the graph.
Which statement best compares the solubility of these substances?
KCl is more soluble at 20°C than NaCl is.
Both substances are equally soluble at 30°C.
KCl will become less soluble at temperatures greater than 40°C.
Both substances have the same solubility from 20°C through 40°C.
Alligators are found throughout Florida. Some of the characteristics of alligators are listed below.
● They are usually found in slow-flowing rivers.
● Females live in a small area.
● They eat fish, snails, birds, frogs, and mammals.
● Males live in areas of more than five square kilometers.
● They reduce their level of activity during winter.
● Females make large nests and protect their young.
Which limiting factor in an ecosystem would have the greatest impact on the alligator populations in Florida?
reduction of shelter and nesting sites
diseases that affect a certain frog species
competition among male alligators for a mate
increase in the rate of water flowing in a river
Wanda lists some heat transfers that can occur in an ocean, as shown below.
1. Warm water moves upward, and cold water moves downward. 2. Energy from the Sun heats the ocean’s surface.
3. Warm air transfers heat to the ocean as it blows across the
ocean’s surface.
4. A stream of hot water from an opening on the ocean floor heats
the water that touches the stream.
Which description from Wanda’s list best represents radiation?
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Scientists who investigate microscopic fossils are known as micropaleontologists. Which of the following would these scientists most likely study?
the rocks that identify the location of ancient continents
the evidence of changes in the climate of ancient Earth
the different elevations of the surface of ancient Earth
the rocks that contain evidence of ancient organisms
Joanna and Mason hang a small box from a string and place two identical electric fans near the box. When they turn on both fans to the same setting, Joanna and Mason observe that the box begins to swing toward the right, as shown in the illustration below.
Joanna claims that she can balance the forces on the box without turning off the fans. Which of the following would most likely produce the change in motion necessary to support Joanna’s claim?
Change the angle of Fan 2 so that it is blowing air onto the bottom of the box.
Move Fan 2 so that both fans are blowing air onto the left side of the box.
Change the setting of Fan 2 so that it is blowing less air than Fan 1 is.
Move Fan 2 so that it is the same distance from the box as Fan 1 is.
The Andromeda Galaxy was previously called the Great Andromeda Nebula because astronomers thought this patch of light was composed of glowing gases. In the 1900s, scientists determined the nebula was actually a spiral galaxy. Which of the following describes the relationship between this galaxy and other astronomical bodies?
This galaxy is the largest star and is found in the universe.
This galaxy is surrounded by thousands of stars in the universe.
This galaxy includes a universe that is composed of millions of stars.
This galaxy is one of billions of galaxies in the universe and contains billions of stars.
Throughout history, scientific knowledge has changed. Which of the following resulted in an important change in scientific knowledge?
the observation of phase changes of the Moon
the discovery of the function of the DNA molecule
the development of a hypothesis describing possible life on Mars
the prediction of when a comet would be most clearly visible from Earth
Cassandra flashes a beam of white light toward a prism. The prism separates the white light into different colors. Which of the following causes the separation of the white light?
The white light is concentrated.
The white light is absorbed.
The white light is refracted.
The white light is reflected.
Nyles used a microscope to observe two different types of cells. Drawings of the two cells are shown below.
Which of the following best contrasts the functions of the cell parts labeled X and Y?
Part X stores water for future use, whereas part Y releases water out of the cell.
Part X holds the structures in place in the cell, whereas part Y keeps all molecules from leaving the cell.
Part X provides energy for the cell, whereas part Y helps with photosynthesis in the presence of sunlight.
Part X regulates substances that enter or exit the cell, whereas part Y provides protection and support to the cell.
A student claims that studying rock layers on the side of a mountain would show that Earth has changed over geologic time. Which type of evidence from the rock layers best supports this claim?
Some rock layers are solid, and other rock layers have holes that store water.
Rock layers that are composed of sand and silt are found in different locations.
Rock layers that are thick and smooth are deeper than rock layers that are thin and rough.
Some rock layers contain fossils of plants, and other rock layers contain fossils of marine animals.
In 1980, a scientific journal published an article describing the observations that led to a hypothesis. The hypothesis stated that an asteroid striking Earth brought about the extinction of the dinosaurs. Which of the following would best provide support for a scientific hypothesis?
opinions and personal beliefs
new evidence and personal opinions
new evidence and additional observations
additional observations and informed predictions
Ms. Brooks demonstrated phase changes to her class. She lit a candle and let the melting wax drop into a beaker of cold water, as shown below. The temperature of the water was four degrees Celsius (4°C).
Which statement best explains what happened to the wax as it came in contact with the cold water in the beaker?
The wax changed from a liquid to a solid as it gave off heat to its surroundings.
The wax changed from a liquid to a solid as it increased in temperature.
The wax remained in the liquid phase as it decreased in temperature.
The wax remained in the liquid phase as it absorbed heat.
The planet Saturn takes 10,747 Earth days to complete one orbit around the Sun. Why does Saturn take longer to complete one orbit around the Sun than Earth does?
Saturn has stronger gravity.
Saturn is farther from the Sun.
Saturn has a thicker atmosphere.
Saturn is the only planet with rings.
A group of students slowly poured 100 milliliters (mL) of vegetable
oil, 100 mL of colored water, and 100 mL of corn syrup into a 500-mL beaker. The students observed the beaker after 5 minutes and recorded their observations in their science notebooks. Which of the following are the students most likely trying to compare?
the volume of the liquids
the density of the liquids
the weight of the liquids
the color of the liquids
A chemist observes a reaction between two substances in a closed container. Which of the following would most likely happen if the temperature is increased inside the container?
The rate of the reaction would increase.
The mass of each of the atoms would increase.
The two substances would release nuclear energy.
The two substances would not change into different compounds.
Animal Activity
Coyotes and wild boars are animals that are active during the day and night. Both animals live in areas where human populations are increasing. Scientists collected data from various areas worldwide and concluded that the amount of coyote and wild boar activity is related to the population size of humans. The percentage of activity that occurs at night in different habitats is shown in Figure 1.
Scientists in California collected coyote droppings in habitats with small and large human populations. They used these data to determine the time of day and night that coyotes consumed prey. The scientists’ data are shown in Table 1. Click on the picture to zoom in.
Which of these is the most important role of technology in the wild boar study?
reducing bias during analysis and interpretation of the data
producing graphs from the averages calculated by researchers
collecting data over long periods of time and across great distances
controlling external variables that are difficult for researchers to observe
Coyotes share their habitats with gray foxes, which are related to coyotes and are active at night. Gray foxes eat plants and animals, including some of the same animals that coyotes eat. Which of the following describes the most likely effect that coyotes have on gray foxes in locations with large human populations?
decreased exposure to parasites and disease
increased protection from larger predators
decreased cooperation when finding food
increased competition over prey species
Scientists in Poland used radio collars to track the movements of wild boars in each type of habitat during different times of year. The average daily distances wild boars traveled in each habitat, in kilometers (km), are shown in Figure 2.
Which statement describes how humans in an expanding city most likely affect the wild boars that live nearby?
Humans decrease the effect that natural predators have on wild boars.
Humans remove the plants that wild boars rely on for food and shelter.
Humans create new ponds and lakes that wild boars must travel around.
Humans increase the area of fields available for wild boars and other wildlife.
All plants and animals have threadlike structures in the nucleus of each cell. These structures contain a set of instructions in the form of DNA. Which of the following terms identifies these threadlike structures?
alleles
chromosomes
cytoplasm
mitochondria
Earth’s atmosphere is important to the living organisms of the biosphere. Which of the following describes how the atmosphere best protects living organisms?
by providing enough carbon dioxide in the ocean to support sea animals
by changing oxygen into nitrogen, which can be used as a nutrient for animals
by refracting visible light, allowing certain animals to see and capture their prey
by trapping electromagnetic radiation, keeping temperatures within a range best suited for animal life
A yeast is a single-celled organism that can reproduce sexually or asexually. Which of the following would confirm that a yeast had reproduced asexually?
offspring with its own unique genetic information unlike that of the parent
offspring with the same genetic information as each of its two parents
offspring with half the genetic information from each of two parents
offspring with the same genetic information as the parent
Two Olympic cyclists rode their bicycles on an oval track. The graph below represents the number of 500-meter laps they completed.
Based on the graph, which statement best describes the motion of the cyclists as they rode their bicycles?
Both cyclists made stops about halfway through their rides.
Both cyclists rode their bicycles at about the same speed.
Cyclist 1 rode about twice as fast as Cyclist 2.
Cyclist 2 made more stops than Cyclist 1.
Scientists have collected large amounts of evidence that support the idea shown in the illustration below.
Which of the following is a scientific theory that is best supported by this evidence?
evolution
superposition
plate tectonics
universal gravitation
A scientist observes six lady beetles of the same species that live in the same location. Each of the lady beetles is a different shade of orange or yellow, and each has a different number of black spots. Which statement most likely explains how these differences relate to the evolution of the lady beetle species?
These differences show that the species may learn to adapt to a warmer and drier climate.
These differences show that damage to plants in the habitat has caused the species to develop additional spots.
These differences show that mutations have developed in the population as the species was exposed to pollutants.
These differences show that there is genetic variation in the population that may allow the species to survive changes to its habitat.
Ocean currents in the Pacific Ocean and the Atlantic Ocean affect climate and weather patterns in the United States. The map below shows some of these ocean currents.
A student researches climate data and determines that the eastern United States usually has higher humidity than the western United States does. Based on the ocean currents shown, which statement best explains the difference in humidity?
The air mass in the Atlantic Ocean is warmer than the air mass in the Pacific Ocean is, and a warmer air mass holds more water vapor than a colder air mass does.
The air mass in the Pacific Ocean is colder than the air mass in the Atlantic Ocean is, and a colder air mass causes more evaporation than a warmer air mass causes.
The cold ocean current in the Pacific Ocean causes stronger winds than the warm ocean current in the Atlantic Ocean causes, and moisture evaporates from the Pacific Ocean air mass.
The warm ocean current in the Atlantic Ocean produces denser air masses than the cold ocean current in the Pacific Ocean produces, and the dense air mass in the Atlantic Ocean cannot release precipitation.
Dionne observes her science teacher testing a sample of an unknown substance. She recorded her observations in the table shown below.
Which test would provide evidence of a chemical change?
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