Science EC-6 Second Test

In a temperate forest ecosystem, which of the following organisms is a primary consumer?

deer

Which of the following substances would be safest for use in a fifth-grade science experiment?

dish soap

Samuel rides his bike around the park and over to the pond, and then back to where he started. Which is greater: the distance he traveled or his displacement?

distance

During a sixth-grade unit on suspensions, Mr. Ricky teaches that the color of a suspension depends on how light reflects on the solutes. He uses the examples of glacial lakes, which contain silt from the glacier's movement. When sunlight hits the lake and reflects from this suspended silt, the lake appears a spectacular turquoise blue or green color. Of the following student activities, which would be most useful to include while assessing students' understanding of his unit on suspensions?

drawing a diagram of why glacial lakes are blue

The flow of electrons through a conductive material is also known as what?

electric current

A farmer wonders why water is not moving through his irrigation system. He checks the water pump and finds it is not plugged in. Once he plugs the pump in, water again moves through the system. Which of the following energy transformations occurs when the pump pushes water through the system?

electrical energy to kinetic energy

Carbon (C) is classified as which of the following?

element

To begin, the teacher holds up a metal rod and a pencil and says, "Which object will stick to the magnet?" The students shout out different responses until the teacher places the magnet on each object. This portion of the lesson focuses on which area of the 5-E learning cycle?

engage

Pressures driving natural selection include all of the following except:

equal populations of all organisms

A school's PTA volunteered to make outside improvements to the school. A pile of sand and river rock was delivered to the school for the repair of the playground. After a week of rain, the river rock was still piled high, but the sand was no longer in a pile. What could have happened to the sand?

erosion

She builds a leaf rubbing center with 5 different kinds of leaves. The students can view the leaves under a microscope and use various other tools to conduct observations. Which phase of the 5-E model is this center demonstrating?

exploration

A student measures the volume of 12.8 ml of liquid with a graduated cylinder, checking the measurement three times to obtain volumes of 13.2 ml, 13.2 ml, and 13.1 ml. The student's measurements are:

precise but not accurate.

A grasshopper feeds on a corn plant. The grasshopper is eaten by a chicken, which is then slaughtered and eaten by a farmer. To which trophic level does the grasshopper belong?

primary consumer

What are the functions of the integumentary system?

protects body, regulates temperature, and eliminates wastes

Which two subatomic particles can be found in the nucleus of an atom?

protons and neutrons

A second-grade teacher is planning to teach a lesson on measuring mass. What would be the best introductory activity for his students?

providing balance beam scales and various objects to compare

A scientist is performing an experiment to determine the conductivity of a specific substance. Which of the following actions would increase the reliability of the results?

recording the results of repeated experiments

Which of the following colors of visible light has the longest wavelength?

red

Which of the following body systems is responsible for taking in oxygen and expelling carbon dioxide?

respiratory system

Which of the following rock types will form when windswept sand is buried and hardened into a solid mass?

sedimentary

Which of the following geological processes is most likely to move rock from below the surface of the Earth to the surface?

volcanic activity

An equatorial air mass that originates over land would most likely be described as:

warm and dry.

Casey is playing with her yo-yo. She performs an "around the world" trick, in which the yo-yo travels up and around in a circle before returning to her hand. At which point in its circular path would the yo-yo have the least potential energy?

when the yo-yo is at the bottom of its circular path

Which quality would a scientist be measuring if he were using an anemometer?

wind speed

Which of the following is a primary way carbon dioxide is naturally taken out of the atmosphere?

photosynthesis

If there is a full moon tonight, how many days will pass until the next full moon?

28

A tug-of-war rope is being pulled with a force of 80 N to the left by Jeff and a force of 50 N to the right by Rico. What is the net force acting on the rope?

30 N to the left

A kite flying above a playground is pushed by the wind toward the north with a force of 25 N. The kite string pulls on the kite toward the south with a force of 20 N. What is the net force acting on the kite due to these two forces?

5 N to the north

Black colored fur is dominant over white colored fur in hamsters. A black colored hamster (Bb) is mated with a purebred, white colored hamster (bb). What percentage of their offspring will have the genotype Bb?

50%

Red flowers are dominant over white flowers in roses. A heterozygous red flowering rose is mated with a purebred, white colored rose. What percentage of their offspring will have the genotype rr?

50%

If 2.2 lb = 1 kg, and Mary weighs 120 lbs, how much does she weigh in kg?

55 kg

If there is a first-quarter moon tonight, how many days will pass until the next full moon?

7

A classroom is 7.5 meters wide. How many centimeters wide is the room?

750 cm

Consider the following Punnett square. If A is dominant over a, what percentage of the offspring would be expected to show the dominant phenotype?

A a a Aa aa a Aa aa NOT 25%

Janeth is at the lake with her friends on a beautiful day. By evening, she and her friends are hurrying towards shelter from an oncoming thunderstorm. What is the most likely cause of this sudden thunderstorm?

A cold air front has met a warm air front and forced the warm air up. The moisture in the air condensed into thunderheads.

Which of the following statements best illustrates how to help students develop ethical thinking in science?

A regular and consistent focus on how science can affect society, for good or bad.

How long does it take for the earth to make one complete rotation on its axis?

About 24 hours

Which of the following statements about chimpanzees most effectively relates structure to function?

Chimpanzees have opposable thumbs on all four hands to swing from trees.

After teaching a unit on evolution, Mrs. Reed asks her students to write a paragraph on the likely reason that modern African Elephants have big ears while Asian Elephants have smaller ears. One of her students turns in the following: "All elephants had small ears. One year, it was very hot in Africa. Some of the African elephants started to grow bigger ears to help release more heat and cool off. The elephants that grew the biggest ears lived and were able to have more offspring. The offspring were born with the bigger ears from their parents." What is the student's misconception?

Acquired traits are passed onto offspring.

Certain plant species can reproduce asexually through the processes of budding or through spore dispersal. Which of the following is a disadvantage for plants that employ this type of reproduction?

All offspring are genetically identical, so a disease can wipe out an entire population.

Newton's third law of motion states that for every action there is an equal and opposite reaction. Which of the following is the best example of the application of this law?

An airplane moves in the opposite direction of the air pushed out by its engines.

Which of the following is false?

High tides only occur on the side of the earth closest to the moon.

Which of the following interventions would be most beneficial for a visual learner who is struggling to differentiate between DNA and RNA?

Ask the student to color a picture of the DNA molecule and RNA molecule. Ask the student to highlight the differences.

A student is struggling to differentiate between artificial selection and natural selection. Which of the following interventions would best help this student?

Asking students to pair up and create a Venn diagram of artificial selection and natural selection together.

In a cross between a black guinea pig and a brown guinea pig, all of the offspring are black and none of the offspring are brown. Which of the following is most likely true?

Black fur color is dominant in guinea pigs.

Susanne and Xavier are workers on a road construction crew. When lifting a rock, Xavier lifts the rock straight up, but Susanne uses a lever, as shown.

Both do the same amount of work.

A population of lizards, some with green coloring and some with brown coloring, is introduced into a field that is mostly dirt. A few generations later, the majority of the lizards have brown coloring. Which of the following best explains this change?

Brown colored lizards are better able to hide from their predators.

The rusting of an iron chain can be classified as which of the following?

Chemical change

Ms. Medure's fourth-grade class is studying volcanoes. She chooses to have her students build papier-mâché models of volcanoes, both to help them learn volcanic structure and also to help them learn the benefits and limitations of scientific models. In addition to building the models, which of the following activities best supports her learning goals about scientific models?

Class discussions on how the models are like and different from real volcanoes.

Which is the most age-appropriate approach for teaching early elementary students to understand the meaning of "renewable" when discussing renewable and non-renewable resources?

Compare how long it would take to grow, gather, or form more of each resource (i.e. grow a tree, gather sunlight, or make coal).

Which of the following units is most appropriate to measure the volume of a solid?

Cubic centimeters

A meteorite impact with Earth could send large amounts of dust into the atmosphere. Which of the following changes is most likely to follow from an increase in atmospheric dust?

Decreased transmission of solar radiation causing lower global temperatures

The uneven heating of the Earth results in which of the following?

Deserts commonly found near the Tropic of Cancer and Tropic of Capricorn.

Some traits or characteristics in humans are either dominant or recessive. For example, brown eye color is dominant over blue eye color. If an individual has two alleles for blue eyes, his eye color will be blue. However, if he has one allele for brown eyes and the other one is for blue eyes, his eye color will be brown. Based on this example, which of the following statements is true?

Dominant characteristics mask the presence of recessive characteristics.

Which of the following activities would contribute to global warming?

Driving a gasoline-powered car

Which of the following best explains why a large volcanic eruption decreases the average temperature of a region for several years after the eruption?

Expelled ash and dust block solar radiation.

A teacher of early elementary students would like to incorporate additional digital technology into classroom learning. Which of the following is the most effective approach?

Find ways to purposefully integrate technology into current lesson plans, such as using science-based programs to supplement core content science instruction.

Which of the following is not a major component of the earth's atmosphere?

Fluorine

A teacher plays a game-show style review game with her students halfway through the unit. Which of the following types of assessment is this an example of?

Formative assessment

Which kingdom would an organism belong to if it were a eukaryotic multicellular heterotroph with chitin in its cell walls?

Fungi

Which of the following can be attributed to active geothermal activity?

Geysers

A teacher wants his students to learn about different forms of energy in everyday life. Which of the following is the most engaging way to start a lesson that relates to the lesson goals and encourages students to see themselves as scientists?

Give students time to rotate through several hands-on science experiments that demonstrate the transformation of energy from one form to another.

Sally would like to measure the volume of liquid water produced by a reaction. Which of the following tools would be most appropriate for her to use?

Graduated cylinder

Which of the following is the best example of a behavioral adaptation?

Grizzly bears in Alaska will hibernate in the winter.

Mr. Zeno has prepared mixtures of sand and pebbles. He divides his students into groups and tells them they are teams of geologists with a task of separating a mixture. Which of the following activities would best help students learn the process of doing science?

Have many different tools available for students use, including tweezers and a wire mesh. Briefly explain how to use each tool. Encourage the groups to decide how to complete the task.

After reading a story about a world that runs out of natural resources, a second-grade teacher wants students to think deeply about what they could do to prevent this in our world. Which of the following activities best supports critical thinking and relates to the lesson goal?

Have small groups of students discuss and evaluate their own thoughts about what they could do personally to conserve resources.

During a unit on organisms and environments, Mr. Woodland wants his second-grade students to identify factors in the environment that affect plant growth. Students design investigations that involve growing bean plants in paper cups and exposing the plants to environmental variables of their choice. After the beans sprout, the students measure and record the heights of their bean plants. At the end of the investigation, students will be asked to present their data in a way that will be quick and easy to understand. Which of the following is the best way to incorporate technology into this lesson?

Have students record and graph their data in a spreadsheet that they can access each time they make a measurement.

Students are asked to build rubber band cars that will travel long distances. After the students build and test the cars, the teacher asks the students to develop hypotheses about the effects of changes they might make to their cars. Which of the following questions would best encourage students to come up with scientifically testable hypotheses about possible changes?

How could you change your car to make it travel further?

A student is investigating the growth of Elodea under different light sources. Which of the following is the best research question for this student?

How does the type of light source affect the rate of photosynthesis of Elodea plants?

Why is it important for scientists around the world to adhere to the same system of measurement?

It allows for easier and more consistent communication of results.

A hockey puck is sliding to the right at constant speed. Suddenly forces of 10 N to the left and 10 N to the right are applied to the puck at the same time. What is the resulting motion of the hockey puck?

It continues to move right at constant speed.

Mrs. Conner wants to pre-assess the class regarding their knowledge of the periodic table of elements, inquire about their interest in the subject, then follow up with what students have learned. Which of the following formative assessment tools would be a good choice for Mrs. Conner?

K-W-L chart

Which speed vs. time graph best represents the motion of a car slowing at a constant rate as it approaches a stoplight?

L backwards /

Which of the following scientists won two Nobel Prizes, one in physics and one in chemistry, and discovered the elements Radium and Polonium?

Marie Curie

Students in Ms. Carson's class are having trouble understanding how genetic variation allows natural selection to happen. What can Ms. Carson do to address this misconception?

Ms. Carson can buy a bag of multi-colored fruit candy and ask each student to pick out their favorite flavor. Afterwards, Ms. Carson can show students the candy so they can see that their least favorite flavors are less likely to get picked.

A sixth-grade science teacher is teaching an inquiry-based unit on animal behavior. Which of the following questions would best lead to the development of an investigation relevant to students' lives?

NOT most dangerous pet!

Which of the following topics might a teacher want to review before starting a lesson on the carbon cycle?

NOT water cycle

Which of the following sources of energy is nonrenewable?

Natural Gas

Which of the following is the furthest planet from the sun?

Neptune

Which of the following is true about stars?

Star color is dependent upon their temperature.

A fourth-grade class built a model of the solar system. Each student group worked in isolation and was responsible for building one assigned representation of a planet, moon, or other object. Which limitation is the greatest concern for the class, with regards to the solar system model, once it is put together?

Planet sizes will not be built to scale

Which of the following is a key characteristic of scientific inquiry?

Scientific theories are open to change as new information is discovered.

Which bodily process aids in maintaining homeostasis?

Shivering when cold

Which of the following activities would provide the most beneficial learning experience for a third-grade class studying the planets and their positions relative to each other?

Students create a scaled-down model of the solar system on the field using inflatable planets.

In a lesson about friction, students in a fourth-grade class work in groups to measure the speeds of differently-shaped objects sliding down a slope. The students are instructed to measure the speed of each object three times with a stopwatch. Which of the following best describes a learning outcome of this activity?

Students practice using repeated trials to decrease the margin of error.

The Moon's gravity pulled on the Apollo 11 rocket as it landed on the Moon. Which of the following statements correctly compares the Moon's gravitational force on Apollo 11 with Apollo 11's gravitational force on the Moon?

The Moon and Apollo 11 exerted the same amount of force but in opposite directions.

A frozen ice cream bar was left in the sun and melted. Which statement is true regarding the physical properties of the ice cream bar after it melted?

The arrangement of molecules had changed.

Mr. Sandberg's students are frustrated because they all performed well on the homework assignments, but the large majority of them failed the most recent exam. In reviewing the test questions, the students noticed they were much more complex than the homework questions. The students approach Mr. Sandberg with their concern that the test has questions they were not prepared to answer. Which of the following best describes the students' concern about the assessment?

The assessment does not have content validity.

Which statement best describes why a cork floats in water?

The density of cork is less than the density of water.

A test given at the end of a unit on weather and climate is an example of:

a summative assessment.

A forest was cleared and turned into a field of organic soybean plants. Which of the following most likely occurred?

The number of insect species decreased.

Why does a red dress appear red when white light shines on it?

The pigments in the red dress reflect red light and absorb most other colors.

Which of the following can be true of compressional waves with a high frequency?

They are sound waves with a high pitch.

Which of the following is not true of compounds?

They cannot contain more than one element.

Which of the following would result if two objects with opposite electrostatic charges are placed near one another?

They will attract one another.

Which of the following functions are performed by a plant's stomata?

Transpiration of water out of the leaves.

Which of the following scenarios is not an example of maintaining homeostasis?

Verbal communication

Which of the following is the best example of an acquired trait?

a child perfecting how to play basketball

Pieces of broken rock often become cemented together to form a new rock. This rock is referred to as:

a sedimentary rock.

Which of the following substances would be attracted to a magnet?

a steel paperclip

Which of the following environmental pressures would not be a primary contributor to the process of natural selection?

abundance of food

Which nitrogen base pairs with thymine in the DNA molecule?

adenine

Mr. Chang's fourth-grade students are just finishing a unit on solar energy. They built solar cookers and solar heaters, and the students are excited about the potentials of using solar energy in the future. Which additional activity would best help students make wise decisions about using solar energy when they are home and business owners?

an age-appropriate cost/benefit analysis

An increase in carbon dioxide (CO2) emissions on Earth is thought to be responsible for which of the following?

an increase in Earth's average temperatures

Ms. Santiago, a fourth-grade teacher at Santine Elementary school, was given a grant to purchase a weather station for her class. After installing the station, Ms. Santiago has had her students record the weather each day for an entire month. One day Ms. Santiago divides her students into groups and asks each group to categorize and draw conclusions from their month-long wind direction measurements. Of the following science practices, which one is the primary focus of this lesson plan?

analyzing and interpreting data

The wind speed in two different cities was recorded on a line graph. Which instrument was most likely used to gather the data recorded?

anemometer

During a unit on cell structures, a teacher would like to gauge student understanding. Which of the following formative assessments would be most useful for this purpose?

asking students to write an essay describing the differences between cell types

Which of the following is an example of a negative feedback system?

body temperature regulation

Which of the following is a reactant of the photosynthesis reaction?

carbon dioxide

Having students create three-dimensional models of a generic animal cell would be most suited for teaching which of the following biological concepts?

cell organelle structure

Global weather patterns or short-term climatic changes can be impacted by which of the following?

changes in global winds and ocean currents

A basketball player holds a basketball, ready to jump and shoot the ball. The player jumps in the air and shoots the ball toward the basket. Which of the following energy transformations occurs to power the player's jump shot?

chemical energy to kinetic energy

Which of the following systems in the human body functions as the system responsible for transporting food and water waste?

circulatory system

A polar air mass that originates over land would most likely be described as:

cold and dry

Cattle egrets are birds that live near cattle because as the cattle graze, insects in the ground are stirred up to the surface. When the insects are stirred to the surface, the birds eat the insects. The cattle are unaffected by the birds or the insects. This relationship between the cattle egrets and the cattle can best be described as:

commensalism.

A teacher uses a long copper pipe in a demonstration during a lesson on heat transfer. The teacher puts one end of the pipe on a warm hot plate and allows the far end of the pipe to extend over the desk. The teacher asks one student to feel and describe the changes in the temperature with time along the length of the pipe. Which of the following is the teacher demonstrating?

conduction

As a demonstration during a unit on heat transfer, a teacher heats one end of a long metal rod and later measures the temperature at different positions along the rod. Which of the following processes is demonstrated by the range of temperatures?

conduction

Weather systems, plate tectonics, and plant growth are three systems that experience change. Which of the following is a unifying concept that is directly involved in all three systems?

conservation of energy

Ms. Medure's fourth-grade class is studying volcanoes. Which of the following activities linked to science practices best supports the instruction of "change in natural systems" as related to volcanic eruptions?

constructing explanations about how landscapes are altered by volcanic activity

Which of the following is an example of a positive feedback system?

contractions during labor and childbirth

As a demonstration during a unit on plate tectonics, a teacher holds an aluminum pie plate over a smoky candle and has the students observe how the smoke spreads and moves around and over the edges of the plate. Which of the following is demonstrated by the movement of the smoke?

convection

Which type of tectonic plate boundary involves two continental plates moving toward each other?

convergent

Of the following, which contributes the most to water pollution in streams?

fertilizers and pesticides

Which of the following correctly lists the primary function of the leaves of a plant?

gas exchange and photosynthesis

Comets are composed of:

gas, dust, and ice.

Mr. Harris has several English-language learners in his classroom. He is currently beginning a unit about circuits. Which of the following activities will be most effective in engaging Mr. Harris' English-language learners in a lesson?

giving students bulbs, batteries, and connecting wires and asking them to try to make the bulbs light up

Which of the following is the principal type of energy stored behind a hydroelectric dam?

gravitational potential energy

Which of the following activities best helps students practice the process skill of classification?

grouping minerals according to their colors

Which of the following characteristics always describes a liquid?

has a non-fixed shape has a fixed volume

A third-grade science teacher is teaching a lesson on erosion. He wants to incorporate technology to help students explore these issues across history and in current climates around the world. An example of an appropriate activity would be to:

have students use the internet to find accounts of the Dust Bowl and current farming practices that prevent erosion.

Which activity would be appropriate for a second-grade class studying the water cycle?

having groups use easily accessible materials (such as rocks, popsicle sticks, etc.) to build a 3D model of the water cycle

A teacher would like to assess the students' understanding of how the other Solar System planets differ from Earth. Which of the following would be the most effective way to do this?

having student pairs brainstorm what humans would need to live on the other planets

Following an investigation on how the length of shadows changes throughout the day, Mr. Vasquez would like to assess his students' knowledge of the relationship between shadow length and time. Which of the following would be the best assessment to use?

having students draw pictures of shadows at various times of the day

Students in a first-grade class are learning which colors result when primary colors are combined. Which of the following is the most effective way to assess student understanding of the concept?

having students select and combine primary colors of clay to make specified secondary colors

Which of the following best describes the frequency and wavelength of a sound with a high pitch?

high frequency and short wavelength

Imagine that the US president's science advisor wants to perform a risk assessment of several scientific proposals before recommending which should be fully supported by federal funds. Which of the following steps should the advisor take first?

identifying the problems that need solutions

Which of the following rock types will form when lava cools quickly above ground?

igneous

Freshwater is a limited resource that is needed to sustain much of life on Earth. Which of the following reduces the availability of fresh drinking water for humans and animals?

increased crop irrigation

Heart disease is a major threat to human life in the United States. Which of the following lifestyle changes is the most likely to reduce the incidence of heart disease?

increasing the amount of exercise

A wind turbine converts:

kinetic energy into electrical energy.

Which of the following is the responsibility of the teacher with regard to the use of chemicals?

knowing the chemicals used in each laboratory experiment and reviewing the material safety data sheet for them

Which macromolecule provides long-term energy storage and insulation?

lipids

Quartz can be classified as which of the following?

mineral

Which organelle is responsible for generating large amounts of adenosine triphosphate (ATP)?

mitochondria

Which organelle is responsible for breaking down glucose into energy for the cell?

mitochondrion

Albinism (lack of pigmentation) in an organism is most likely the result of which of the following?

mutation

The remora is a fish that attaches itself to a shark by using a suction disk on its head. The sharks do not like to eat the remora, and the remora feeds on parasites that live on sharks' skin as well as the shark's leftovers. This is an example of which of the following?

mutualism

During a fission reaction in a power plant uranium atoms break apart and emit energy used to make steam. Which of the following energy transformations takes place during this process?

nuclear energy to thermal energy

Which of the following is the largest structure within a snake?

organ system

Of the following, which is most appropriate to do after testing a hypothesis?

organize data

The earth is divided into four distinct layers. Which layer is composed of very hot, liquid material?

outer core

Ticks are mites that attach themselves to animals, such as dogs, and suck blood. In doing so, ticks transmit diseases, such as Lyme disease, to the animals. Which type of interaction does this describe?

parasitism

Ms. Jones assigns her students a task in which they must act out a play with students representing color-coded chromosomes. The play must illustrate the process of crossing-over, and show the resulting cells having different color combinations than the parents to show that they are genetically different. This would be a good activity for students to learn about which topic?

sexual reproduction

Of the following, which is a sedimentary rock?

shale

Carbonated water is made by dissolving carbon dioxide gas in water. Carbonated water is classified as which of the following?

solution

After a completed lesson on reflection, Ms. Zoya looks at herself in a hand-held mirror, smiling and commenting on her reflection. She then tries to look at her image in a piece of white paper and acts puzzled because she cannot see herself. She asks students why she can see herself in a mirror but not in the paper, writes their theories on the board, and asks for ideas on how to test their theories. What concept about light is Ms. Zoya most likely using as she teaches the science process of experimental design?

specular and diffuse reflection

Mrs. Campbell, a third-grade science teacher, is teaching conservation practices. What can her class do to demonstrate they have learned to make informed choices, based on the needs of the environment?

start a paper and plastic recycling program

A liquid is heated to its boiling point temperature. If further heat is added to the liquid it will:

stay at its boiling point temperature until all of the liquid has evaporated.

Which of the following is an abiotic factor in an ecosystem?

temperature

Mr. Shields is teaching a unit on magnetism with his third-grade students. Many have a misconception that all metals are attracted to magnets. Which of the following activities would most effectively help his students think critically about this statement?

testing magnetic attraction with a variety of metals

Which of the following best accounts for day and night on Earth?

the Earth's rotation on its axis

Where is the majority of nitrogen on Earth?

the atmosphere

Students perform an investigation to compare the relative specific heats of sand, water, and soil. They fill plastic cups with the same mass of each material, place a temperature probe in each sample, and put the samples the same distance beneath identical flood lamps. Students record temperature data for 2 minutes while the lamps are on, and continue recording data for 1 minute after the lamps are turned off. Which of the following is the dependent variable in this experiment?

the change in temperature of the materials

When deciding to house a live animal in the classroom, the risk of a potential health hazard to the student or animal must be weighed against the educational value added. What guidelines must first be considered to address this potential hazard, prior to making a choice of getting the animal for the classroom?

the children that might be affected by allergic symptoms

A weatherman on the local news is describing a cold front reaching and pushing up warm air later in the day. Which of the following is the weatherman most likely explaining? Select all answers that apply.

the development of thunderstorm clouds the likelihood of rain

Michelle pours lemonade powder into a cup of ice and water. She stirs it with a spoon to mix up the powder more quickly. What is the solvent?

the liquid water

During a lesson on waves, Ms. Chavez asks her students to stand side-by-side in a long line and link elbows. She asks them to be ready to squat when someone tugs their elbow down and stand back up when someone tugs their elbow up. Ms. Chavez goes to one end of the line, links elbows, squats and stands back up. As she squats, she naturally tugs downward on the elbow of the student next to her, who then tugs downward on the next student and so on. As she stands again she naturally tugs upward on the student next to her, and the signal moves down the line. The result is a wave that starts with Ms. Chavez and travels down the line of students. Each student squats and stands as the wave passes. Which of the following concepts about waves is Ms. Chavez most likely trying to teach?

the nature of a transverse wave

A 5th-grade teacher provides models of various visuals that her students can incorporate into their research presentations. Which of the following would most reasonably be visually represented by a flow chart?

the process of completing phone calls in the first year following the invention of the telephone

Mr. Reynolds is working through a unit on healthy lifestyles. He wants to incorporate the leading cause of preventable death in the United States. Which of the following causes of death should Mr. Reynolds use?

tobacco use

Which of the following would not be characterized as an adaptation to warmer than average global temperatures in recent decades?

trees dropping leaves in winter

Which of the following activities best helps students practice the process skill of observing?

using a magnifying glass to inspect the small features on the surface of a leaf

Ms. Mendez wants her students to practice process skills during a unit on the rise of mammals after the dinosaur extinction. Which of the following activities best helps students practice the process skill of communicating?

using evidence to explain why mammals thrived at that time