Earth Science
Space Science
Scientific Investigation
Physical Science
Life Science
100
Convection currents in the atmosphere influence many weather patterns. What property of the air has the most influence on convection currents?
A. the direction of the wind
B. the velocity of the wind
C. the temperature of the air
D. the mass of the air
C. the temperature of the air
✅ Explanation: Convection currents occur due to temperature differences in air, causing movement of warm and cool air.
100
The chart below lists several planets and their distances from the Sun in astronomical units (AU).
Which list correctly orders the length of each planet's year, from shortest to longest?
A. Earth, Mercury, Saturn, Neptune
B. Mercury, Earth, Saturn, Neptune
C. Earth, Mercury, Neptune, Saturn
D. Mercury, Earth, Neptune, Saturn
B. Mercury, Earth, Saturn, Neptune
✅ Explanation: The farther a planet is from the Sun, the longer its orbit (year) takes.
100
Colleen waters the plants in her greenhouse once every day. She wants to find out if the plants will grow more leaves if they are watered more often. She counts the number of leaves on each plant before she starts. She then continues to water half of each type of plant once daily, but she waters the other half of each type twice a day. What is the outcome variable (dependent variable) in Colleen's experiment?
a. the type of plant being grown
b. the number of leaves the plants grow
c. the amount of light the plants receive
d. the number of times the plants are watered
B
Explanation: The dependent (outcome) variable is what is measured — in this case, the number of leaves the plants grow, which depends on how often they are watered.
100
36.
Look at the two pictures below. They show what happened when two solid blocks were each put in a jar containing a liquid.
Based just on what you can see in the pictures, what can you say about the blocks and the jars?
A. Liquid 2 is more dense than liquid 1.
B. The block in jar 1 weighs more than the block in jar 2.
C. The block in jar 1 has a density closer to the density of liquid 1 compared to the desities of the liquid and black in jar 2.
D. The block in jar 1 must be made of metal and the block in jar 2 must be made of wood.
A. Liquid 2 is more dense than liquid 1.
When an object floats in a liquid, how high or low it floats depends on the density of the liquid:
If the liquid is more dense, it provides a stronger upward (buoyant) force, so the object will float higher (less of the object is submerged).
If the liquid is less dense, it provides less buoyant force, so the object will float lower (more of it sinks into the liquid).
100
The picture below show a cell with several parts labeled with numbers.
Which label indicates the part of the cell that contains most of the cell's genetic material?
A. 1
B. 2
C. 3
D. 4
Correct Answer is A
The nucleus is the part of the cell that contains most of the cell’s genetic material (DNA). In standard cell diagrams:
The nucleus is usually a large, central structure, often labeled.
It controls cell activities and stores genetic information.
orrect Answer is
200
Many of Earth's surface features such as mountains or movements such as earthquakes are the result of convention currents. In which layer of the Earth do convection currents occur that cause for formation of mountains and earthquakes?
A. crust
B. mantle
C. outer core
D. innercore
B. mantle
✅ Explanation: Convection currents in the mantle drive plate tectonics, leading to earthquakes and mountain formation.
200
What is the flaw with using apparent brightness rather than absolute brightness to determine the brightness of a star?
a. Apparent brightness does not use the star's color or temperature.
b. Apparent brightness does not take into account the distance of the star from Earth.
c. Apparent brightness is only theoretical; its value cannot be directly measured with equipment.
d. Apparent brightness is only on a comparative scale that determines how bright a star looks from a theoretical distance of 10 parsecs from Earth.
B. Apparent brightness does not take into account the distance of the star from Earth.
✅ Explanation: A star may appear dim because it's far away, not because it's not bright.
200
Mandy wanted to see if a new, environmentally-friendly pesticide will prevent insect damage to tomato plants. After making her hypothesis, she conducts her experiment.
She treats five tomato plants with traditional pesticide and five with the new pesticide. Mandy also leaves five plants untreated as a control. She makes careful notes of how she set up her experiment and then records her data about all of the plants.
Why is it important for Mandy to record her procedures and data accurately?
a. So she can ensure the hypothesis will always be correct.
b. So she can look intelligent when she presents her data
c. So society does not waste money on buying pesticides that do not work
d. So other scientists can replicate the experiment and make sure the results are correct
D
Explanation: In science, accurate data and procedures are crucial so others can replicate the experiment and verify the findings. This helps ensure the validity and reliability of results
200
Which of the following is NOT made up of atoms?
a. heat
b. gas
c. cell
d. solid
A. Heat
Explanation:
Heat is not made up of atoms. Heat is a form of energy — specifically, it's the energy that flows due to a difference in temperature. It comes from the movement (kinetic energy) of atoms and molecules, but heat itself is not matter and doesn’t have atoms.
A gas, a cell, and a solid are all types of matter, and all matter is made up of atoms.
200
Leigh Ann is learning about the differences between inherited traits and learned behaviors in organisms. For example, she knows that being able to read is learned, while having straight or curly hair is inherited. How does a person inherit a trait such as hair texture?
A. through the storage of excess fatty acids in tissues
B. through DNA that is passed from parents to offspring
C. through the breakdown of different proteins during birth
D. through different viruses that are passed from parents to offspring
B. through DNA that is passed from parents to offspring
Explanation:
Inherited traits, like hair texture (straight or curly), are passed from parents to offspring through DNA. DNA contains the genetic instructions that determine traits. Each parent contributes half of the genetic material to their child, and the combination of these genes results in the inherited traits.
300
How do the convection currents in Earth’s mantle directly cause the formation of mountain ranges?
A. By pulling oceanic plates apart and causing sea-floor spreading
B. By pushing continental plates together at convergent boundaries
C. By shifting magnetic poles and raising crustal sections
D. By heating up the crust and causing it to expand
B.
Mantle convection pushes plates together, building mountains.
300
Which observation MOST strongly supports the idea that the universe is expanding?
A. Planets orbiting in ellipses
B. Redshift in the light from distant galaxies
C. Discovery of black holes
D. Presence of cosmic dust clouds
B.
Redshift shows galaxies moving away, indicating expansion.
300
In science, a theory is different from how we use the term "theory" to apply to everyday ideas. The statement, "It's only a theory" might mean something very different than "theory" when used as a scientific term.
What is the best way to explain the word, "theory," when used in science?
a. In science, there is no difference between a law and a theory.
b. In science, there are few principles that can be considered theories.
c. In science, a theory is well supported by observations and/or experimental data.
d. In science, a theory is a completely accurate and reliable fact about natural events.
C
Explanation: A scientific theory is a well-supported explanation of some aspect of the natural world based on a body of evidence from observations and experiments.
300
Based on its location on the partial periodic table shown below, which element would you predict has chemical properties that are most similar to argon (Ar)?
A. Chlorine (Cl)
B. Helium (He)
C. Nitrogen (N)
D. Zinc (Zn)
B. Helium (He)
Explanation:
Elements in the same group (column) on the periodic table have similar chemical properties because they have the same number of valence electrons.
300
In a human body, which of the following represents the highest level of structural organization?
A. an atom in the lung
B. lung tissue
C. the lungs
D. the respiratory system
D. the respiratory system
Explanation:
In the human body, structural organization follows this order from simplest to most complex:
Cells → Tissues → Organs → Organ Systems → Organism
400
The diagram below shows the collision of two tectonic plates in Asia.
What is a result of this collision?
A. Volcanoes erupt periodically.
B. The Tibetan Plateau slowly sinks.
C. The Himalayas increase in height each year.
D. Glaciers on the Tibetan Plateau melt.
C. The Himalayas increase in height each year.
✅ Explanation: The collision of the Indian and Eurasian plates causes the uplift of the Himalayas.
400
What causes the phases of the Moon?
A. the tilt of Earth on its axis
B. Earth's shadow being cast on the Moon
C. the relative positions of the Sun, Moon, and Earth
D. the elliptical orbit that Earth travels around the Sun
C. the relative positions of the Sun, Moon, and Earth
✅ Explanation: Moon phases result from how sunlight hits the Moon and how much of that is visible from Earth.
400
Scientific laws and scientific theories are important to our understanding of the natural world. In what way is a scientific law different from a scientific theory?
a. A law is true in all situations and all circumstances, while a theory is only true in certain instances.
b. A law describes the major ideas of the universe, while theories are based on the smaller ideas of the universe.
c. A law is based on testable facts and data, while a theory is just a combination of one or more hypotheses that have not been tested.
d. A law expresses a relationship between two or more variables, while a theory explains the mechanism of how something happens.
D
Explanation: A scientific law describes what happens (often using math), while a theory explains why or how something happens.
400
All of the following would be helpful in separating a mixture of sand and salt EXCEPT
a. a magnet
b. a glass cup
c. a filter paper and funnel
d. water
a. a magnet
400
A cell can be seen by looking through a microscope. Seeing which of these organelles would let you know that you are looking at a plant cell?
a. mitochondria
b. chloroplast
c. cell membrane
d. nucleus
b. chloroplast
Explanation:
Chloroplasts are organelles found only in plant cells (and some algae). They are responsible for photosynthesis, the process by which plants make their own food using sunlight. If you see chloroplasts through a microscope, you can be sure you are looking at a plant cell.
500
Thomas has a sample of materials and needs to determine its age. He can determine its relative-age by comparing the rock layer the sample came from to another rock layer. Why is it sometimes difficult to determine the age of materials in this way?
a.The oldest layers of rock are too close to the Earth's liquid mantle.
b.The youngest layers of rocks do not contain enough materials to evaluate.
c.The sequence of rock layers can be disturbed by erosion and earthquakes.
d.The rock layers have too many different types of rocks to determine their age.
C. The sequence of rock layers can be disturbed by erosion and earthquakes.
✅ Explanation: These events can disrupt the original layering, making relative dating more difficult.
500
The current model of our Solar System is called the heliocentric model, which means the Sun is at the center. Before scientists developed the current model, which is best supported by the evidence, what was believed to be the center of our solar system?
A. The Solar System had no center because all the planets' orbits were random.
B. A star other than the Sun was the center of the Solar System.
C. A black hole was the center of the Solar System.
D. Earth was the center of the Solar System.
D. Earth was the center of the Solar System.
✅ Explanation: The geocentric model placed Earth at the center before the heliocentric model replaced it.
500
A swimming team wants to select one of three fabrics for their new swimsuits. Each fabric is made of a different material. The team decides to do the following experiment:
They cut the same size pieces from each fabric and wet each piece with the same amount of water. They hang the pieces in the sunlight and they check every two minutes to see if any of the pieces are dry.
What can the team find out about the different fabrics from doing just this experiment?
A. If the amount of water affects how long it takes the pieces of fabric to dry.
B. If the type of fabric affects how long it takes the pieces of fabric to dry.
C. If the amount of water and the amount of light affect how long it takes the pieces of fabric to dry.
D. If the type of fabric, the amount of water, and the amount of light affect how long it takes the pieces of fabric to dry.
B
If the type of fabric affects how long it takes the pieces of fabric to dry.
✅ Since the experiment controls water and sunlight, the only variable is fabric type, so the team can conclude how fabric type affects drying time
500
The chart below shows part of the electromagnetic spectrum.
Which statement is true regarding this part of the spectrum?
A. Violet has the longest wavelength.
B. Violet has the highest frequency.
C. Violet has the lowest energy levels.
D. Violet is not able to be seen by humans.
B. Violet has the highest frequency.
Explanation:
In the visible light spectrum, violet light has the shortest wavelength and the highest frequency and energy.
Red light has the longest wavelength and the lowest frequency and energy.
ROYGBIV
500
Sandra measured her heart rate and her breathing rate at rest and again after doing 50 jumping jacks.
What is the main reason that both her heart rate and her breathing rate went up with exercise?
a. They both sped up to supply her working muscles with enough oxygen to remain in homeostasis.
b. Her lungs and heart ran short on oxygen while she was exercising and sped up to maintain homeostasis.
c. Her muscles were out of shape and required extra blood and oxygen in order to maintain her jumping pace.
d. They both increased in order to carry heat away from her working muscles more efficiently.
a. They both sped up to supply her working muscles with enough oxygen to remain in homeostasis.
Explanation:
During exercise, muscles need more oxygen to produce energy. To meet this increased demand:
The heart rate speeds up to pump more oxygen-rich blood to the muscles.
The breathing rate increases to bring more oxygen into the lungs and remove carbon dioxide.
This helps the body maintain homeostasis — keeping internal conditions (like oxygen levels) stable even when physical activity increases.
600
If the mid-Atlantic Ridge continues spreading, what will MOST likely happen in the next 10 million years?
A. The Atlantic Ocean will shrink, forming a supercontinent.
B. New mountains will form in the middle of the Atlantic.
C. The Atlantic Ocean will widen as plates move apart.
D. Earth’s rotation will slow due to shifting mass.
C.
Seafloor spreading widens the Atlantic as plates move apart. Divergent Boundaries
600
The colors of various main sequence stars are shown below.
Which list correctly ranks these stars in order of increasing temperature?
A. Achernar, Altair, Sun, Barnard's Star
B. Sun, Achernar, Altair, Barnard's Star
C. Barnard's Star, Sun, Altair, Achernar
D. Sun, Barnard's Star, Altair, Achernar
C. Barnard's Star, Sun, Altair, Achernar
✅ Explanation: Red stars are coolest, followed by yellow, white, and blue as the hottest.
600
A paleontologist who is trying to figure out if a meteor impact killed all the dinosaurs would not be able to find an answer by setting up an experiment. Which of the following would be the best way for a paleontologist to approach this problem?
A. search for dinosaur fossils in many places and note where the fossils stop appearing in the rock layers at each location
B. study the evidence a meteor impact leaves in a rock layer, then look for that evidence in the layers of rock that formed after those layers with dinosaur fossils
C. wait for a very large meteor to hit Earth again and see which kinds of animals are killed by it
D. study similar kinds of disasters that result in large animals becoming extinct
B
Explanation: Since paleontologists cannot recreate past events, they rely on geological evidence. Studying rock layers for signs of a meteor impact near the extinction layer helps test the meteor theory.
600
Francesca is drawing a picture of the electromagnetic spectrum. She needs to order the types of electromagnetic radiation from the lowest to highest frequency. Which of the following shows the correct order of the electromagnetic spectrum, from lowest to highest frequency?
A. visible, UV, infrared, X-ray, microwave, radio, gamma
B. radio, visible, microwave, infrared, UV, X-ray, gamma
C. gamma, UV, microwave, infrared, radio, X-ray, visible
D. radio, microwave, infrared, visible, UV, X-ray, gamma
D. radio, microwave, infrared, visible, UV, X-ray, gamma
HINT: Raging Martians Invaded Venus Using X-ray Guns
Explanation:
The electromagnetic spectrum ordered from lowest to highest frequency (and also from longest to shortest wavelength) goes like this:
Radio
Microwave
Infrared
Visible light
Ultraviolet (UV)
X-ray
Gamma rays
600
The infection-fighting cells that are produced by the immune system are manufactured in specific places around the body, for example, in the lymph nodes and the spleen. However, an infection can occur anywhere in the body. How do these infection-fighting cells manage to move around the body and get to the sites of infection?
a. There are lymph nodes every few millimeters all over the body.
b. They are excreted and float freely around the body, hunting infections.
c. They are carried around the body in the circulatory system.
d. They are moved around the body as muscles squeeze against them.
c. They are carried around the body in the circulatory system.
Explanation:
Infection-fighting cells, such as white blood cells, are produced in places like the lymph nodes and spleen, but they travel through the body using the circulatory system (blood vessels). The blood carries these cells to wherever they are needed, including sites of infection or injury.
700
Base your answer to the following question on the map below and on your knowledge of Earth science. The map shows typical weather systems over North America. Letters X, Y, and Z represent locations on the map. The isobars on the map are measured in millibars (mb). Which type of front extends northwest from location Y?
a. warm front
b. cold front
c. occluded front
d. stationary front
B.
Cold Front
Symbol: Blue line with triangles.
Triangles point in the direction the cold air is pushing.
Meaning: Cold air is advancing and forcing warm air upward. Often causes heavy rain or storms followed by cooler, drier air.
Warm Front
Symbol: Red line with semicircles.
Semicircles point in the direction the warm air is moving.
Meaning: Warm air is advancing and rising over cooler air. Usually brings steady rain and warmer temperatures after the front passes.
Occluded Front
Symbol: Purple line with alternating semicircles and triangles on the same side.
Meaning: A cold front catches up to a warm front. This can bring complex weather — rain, thunderstorms, and shifting winds.
Stationary Front
Symbol: Line with alternating red semicircles and blue triangles on opposite sides.
Meaning: Warm and cold air masses meet but neither is strong enough to move the other. This can cause cloudy skies and extended periods of rain.
700
Which statement is true regarding measuring distances in space?
A. An astronomical unit (AU) is larger than a light year.
B. The time taken for light to travel through our Solar System is longer than that for light to travel through the Milky Way.
C. The Earth is one astronomical unit (AU) from the Sun.
D. All of the terrestrial planets are more than one astronomical unit (AU) from the Sun.
C. The Earth is one astronomical unit (AU) from the Sun.
✅ Explanation: 1 AU is the average distance from Earth to the Sun.
700
Alex and Jennifer conducted an experiment to test reaction times in grabbing a meter stick after it is dropped. They each tested 15 friends. Alex dropped the meter stick for his friends and Jennifer dropped the meter stick for her friends while the other one timed the reactions. Jennifer's friends reacted on average, 0.9 seconds faster than Alex's friends. Jennifer concluded that her friends were faster.
Which of the following should she do next to check her results?
A. Try a different reaction time experiment.
B. Try the experiment again, this time using a ruler instead of a meter stick.
C. Repeat the experiment as it was done the first time but using only Jennifer's friends.
D. Repeat the experiment and have one person drop the meter stick for all the friends tested.
Correct Answer:
D. Repeat the experiment and have one person drop the meter stick for all the friends tested.
Explanation:
Option D is correct because it helps control one of the key variables in the experiment: the person dropping the meter stick. In the original experiment, Jennifer dropped the stick for her group and Alex dropped it for his group, which could have unintentionally caused differences in the timing or method. By having the same person drop the stick for all participants, Jennifer can reduce this variable and make the comparison between the groups fairer and more scientifically valid.
700
On a sunny day, Heidi and some of her classmates are playing kickball during PE. She kicks the ball past second base, and it rolls uphill to a stop. She runs to first base, but before she gets any farther, the bell rings and everyone has to go back inside.
Which of these is an example of kinetic energy changing to potential energy?
a. the ball rolling uphill to a stop
b. the bell ringing inside the school
c. the Sun warming the playground
d. the players running from base to base
a. the ball rolling uphill to a stop
Explanation:
Kinetic energy is the energy of motion.
Potential energy is stored energy based on position — like an object sitting at the top of a hill.
When the ball is rolling uphill, it's moving (kinetic energy), but as it goes higher, it gains potential energy because it's climbing against gravity. When it finally stops at the top, all that motion energy has converted into stored potential energy due to its elevated position.
700
Which of the following are the three main classification domains?
A. Fungus, Plants, and Animals
B. Bacteria, Archaea, and Eukarya
C. Protist, Fungus, and Plants
D. Bacteria, Virus, and Eukarya
B. Bacteria, Archaea, and Eukarya
Explanation:
The three main domains used to classify all life on Earth are:
Bacteria: Single-celled organisms without a nucleus (prokaryotes).
Archaea: Also single-celled prokaryotes but different from bacteria in their genetics and ability to live in extreme environments.
Eukarya: Organisms whose cells have a nucleus. This domain includes plants, animals, fungi, and protists.
800
Scientists hypothesize that 66 million years ago an enormous asteroid hit Earth, sending out a cloud of dust into the Earth's atmosphere and spread around nearly all of Earth. This cloud of dust is thought to have contained particples that would have a chemical composition unique to asteroids. Which of the following would be evidence to support this hypothesis?
A.Fossils show that all plant and animal life became extinct.
B. The fossils of ancient trees show very little growth during this time.
C. A large portion of the asteroid is still embedded in the Earth's crust.
D. An identical layer of sediment can be seen in different parts of the world.
D. An identical layer of sediment can be seen in different parts of the world.
Explanation: This global sediment layer suggests a widespread event like an asteroid impact.
800
Based on the distances of the planets from the Sun, which of the following is an accurate comparison?
A. The surface temperature of Earth is lower than the surface temperature of Jupiter.
B. The surface temperature of Mars is lower than the surface temperature of Neptune.
C. The surface temperature of Saturn is higher than the surface temperature of Venus.
D. The surface temperature of Mercury is higher than the surface temperature of Uranus.
D. The surface temperature of Mercury is higher than the surface temperature of Uranus.
✅ Explanation: Mercury is much closer to the Sun, making it significantly hotter than distant Uranus.
800
44.
Vinnie places his cold drink on the roof of a hot car. Which of the following correctly describes what happens next?
A. The temperature of the drink increases as it sends cold into the hot metal of the car.
B. Heat is transferred from the car into the drink and increases the temperature of the drink.
C. Cold is transferred from the drink into the metal of the car, decreasing the temperature of the roof.
D. The temperature of the area under the drink decreases until it is the same temperature as the cold drink.
B. Heat is transferred from the car into the drink and increases the temperature of the drink.
Explanation:
Heat transfer always occurs from a warmer object to a colder object. The hot car roof has more thermal energy than the cold drink. Therefore, heat flows from the car roof into the drink, raising the drink's temperature. Options A, C, and D incorrectly describe heat transfer as the movement of "cold," which is a misnomer. Cold is simply the absence of heat.
800
According to the modern classification system, which list is written correctly from least specific to most specific?
A. species, genus, family, order
B. phylum, class, genus, order
C. class, order, genus, species
D. phylum, order, species, family
C. class, order, genus, species
Explanation:
In the modern classification system (the Linnaean system), organisms are classified in a hierarchical manner from least specific (broad categories) to most specific.
Dear King Philip Came Over For Good Soup
900
Which of the following is true about wind and water changing the size of mountains over many millions of years?
A. The continuous movement of wind and water changes the size of mountains over many millions of years
B. Nothing can change the size of mountains over many millions of years, not even the continuous movement of wind and water.
C. The continuous movement of wind and water changes the size of some mountains, but not all mountains.
D. Even though mountains change in size over many millions of years, the changes are not due to the continuous movement of wind and water.
A. The continuous movement of wind and water changes the size of mountains over many millions of years.
Explanation: Weathering and erosion gradually wear down mountains over geologic time.
900
Jill is creating a model of the Solar System. She uses a basketball to represent the Sun. Additional materials she has available include, from largest to smallest include a tennis ball, a ping pong call, a marble, and a grain of sand. The table below shows additional objects in the solar system that Jill plans to incorporate in her model using the four available materials.
Which object would best represent Earth in Jills model?
A. tennis ball
B. ping pong ball
C. marble
D. grain of sand
C. marble
Explanation: In scale models, Earth is best represented by a marble compared to the Sun as a basketball
900
Two boys wearing in-line skates are standing on a smooth surface with the palms of their hands touching and their arms bent, as shown below.
If Boy X pushes by straightening his arms out while Boy Y holds his arms in the original position, what is the motion of the two boys?
A. Boy X does not move and Boy Y moves backward.
B. Boy Y does not move and Boy X moves backward.
C. Boy X and Boy Y both move backward.
D. The motion depends on how hard Boy X pushes.
C. Boy X and Boy Y both move backward.
Explanation: This scenario demonstrates Newton's Third Law of Motion: for every action, there is an equal and opposite reaction. When Boy X pushes by straightening his arms, he exerts a force on Boy Y. Simultaneously, Boy Y exerts an equal and opposite force back on Boy X. Because they are on a smooth surface, both boys will move backward away from each other due to these forces.
900
Joe has a cat with black fur (BB) and a cat with white fur (bb). What would be the genotype of their offspring?
A. BB
B. Bb
C. bb
D. BBbb
B. Bb
Explanation:
The black fur color (B) is dominant over the white fur color (b). Joe has one cat with black fur (genotype BB) and another with white fur (genotype bb).
1000
Meg designs an experiment to see which of three types of sneakers provides the most friction. She uses the equipment listed below.
1. Sneaker 1
2. Sneaker 2
3. Sneaker 3
4. Spring scale
She uses the setup illustrated below and pulls the spring scale to the left.
In what direction does the force of friction act?
A. To the left
B. To the right
C. Upward
D. Downward
B. To the right
Explanation: Friction opposes motion. Meg is pulling the sneaker to the left. Therefore, the force of friction, which resists this movement, acts in the opposite direction, which is to the right.
1000
In the diagram of a food web below, the arrows show the direction of energy flow. Each arrow points from the organism that is consumed to the organism that consumes it.
Which statement best explains why decomposers are an important part of this food web?
A. They use sunlight to make their own food.
B. They give off oxygen for animals to breathe.
C. They provide camouflage for small animals.
D. They make nutrients available to plants.
D. They make nutrients available to plants.
Explanation: Decomposers, such as bacteria and fungi, break down dead organisms and waste materials. This process recycles nutrients back into the soil, making them available for plants to absorb and use for growth. Without decomposers, nutrients would remain locked in dead matter, and the energy flow in the food web would be disrupted.
1100
The flashlight shown below has no batteries. It is operated by squeezing and letting go of the handle. Inside the body of the flashlight are gears, which are shown below .
Which sequence best identifies the energy transfers that take place within the flashlight to produce light?
A. Kinetic to electrical to light
B. Kinetic to chemical to light
C. Chemical to electrical to light
D. Chemical to kinetic to light
A. Kinetic to electrical to light.
Squeezing the handle initiates the process with kinetic energy (motion). The gears convert this motion into a rotating generator, producing electrical energy. Finally, this electrical energy powers the bulb, resulting in light energy. The absence of batteries eliminates chemical energy as a factor.