GED Science Practice Test

25 practice questions

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1. Question 1 of 25Easy

   A fossil shows a mixture of traits: it has feathers and wings like birds, but also teeth and a long bony tail like reptiles. This fossil is best interpreted as evidence for which claim?

   1. AA. The fossil belongs to neither birds nor reptiles.
   2. BB. Feathers appeared before reptiles existed.
   3. CC. Birds and reptiles share a common ancestor.
   4. DD. Birds evolved from reptiles that could fly.
   Show answer to question 1

   Answer: C. Birds and reptiles share a common ancestor.

   A fossil that combines bird features with reptile features fits a form on a branching lineage connecting the two groups, which supports common ancestry. The claim about flying reptiles goes beyond the text, which says nothing about the fossil's ability to fly.

2. Question 2 of 25Hard

   A student records data on a sample before and after a change. Before: a shiny gray solid that conducts electricity and is attracted by a magnet. After: a reddish-brown powder that does not conduct electricity and is not attracted by a magnet. Which conclusion is best supported by the data?

   1. AA. A physical change occurred because the sample was only broken into smaller pieces.
   2. BB. A chemical change occurred because the properties of the substance changed.
   3. CC. A physical change occurred because the color change was caused by a coating.
   4. DD. No change occurred because the sample is still a solid.
   Show answer to question 2

   Answer: B. A chemical change occurred because the properties of the substance changed.

   The loss of the original properties, such as conductivity and magnetism, shows that a new substance formed, which is a chemical change. Breaking a sample into smaller pieces would change its size but not its color, conductivity, or magnetism.

3. Question 3 of 25Medium

   Passage: After a meal, glucose from digested food enters the blood. The pancreas releases insulin, a hormone that signals body cells to take up glucose from the blood. In type 1 diabetes, the pancreas produces little or no insulin. According to the passage, what happens when the pancreas produces little or no insulin?

   1. AA. The small intestine stops absorbing glucose.
   2. BB. Body cells take up less glucose from the blood.
   3. CC. The kidneys produce more insulin.
   4. DD. The lungs remove excess glucose from the blood.
   Show answer to question 3

   Answer: B. Body cells take up less glucose from the blood.

   Insulin signals cells to take up glucose, so without enough insulin, cells take up less glucose and more remains in the blood. The passage does not say that insulin controls absorption in the small intestine, so that option is incorrect.

4. Question 4 of 25Hard

   A series circuit consists of a 36-volt power supply, a 5.0-ohm fixed resistor, and an unknown variable resistor. An ammeter connected in the circuit measures a total current of 3.0 amperes. What is the resistance of the unknown variable resistor?

   1. AA. 2.4 ohms
   2. BB. 12 ohms
   3. CC. 17 ohms
   4. DD. 7.0 ohms
   Show answer to question 4

   Answer: D. 7.0 ohms

   The total resistance of the circuit is calculated by dividing total voltage by total current (36 volts / 3.0 amperes = 12 ohms). Because the components are in series, the total resistance equals the sum of the component resistances, making the unknown resistance 12 ohms minus 5.0 ohms, which is 7.0 ohms. The value of 12 ohms is incorrect because it represents the total circuit resistance rather than the resistance of the unknown component alone.

5. Question 5 of 25Medium

   A scientist measures the cumulative position of a motorized rover at specific times: At 0 seconds, position is 0 meters. At 2 seconds, position is 6 meters. At 4 seconds, position is 18 meters. At 6 seconds, position is 36 meters. What is the average speed of the rover between 2 seconds and 6 seconds?

   1. AA. 15.0 meters per second
   2. BB. 6.0 meters per second
   3. CC. 9.0 meters per second
   4. DD. 7.5 meters per second
   Show answer to question 5

   Answer: D. 7.5 meters per second

   Between 2 seconds and 6 seconds, the change in distance is 36 meters minus 6 meters, which equals 30 meters. The elapsed time interval is 6 seconds minus 2 seconds, which equals 4 seconds, giving an average speed of 30 meters divided by 4 seconds, or 7.5 meters per second. The value of 6.0 meters per second is incorrect because it calculates the average speed for the entire 6-second journey rather than the specified interval.

6. Question 6 of 25Medium

   A 0.2-kilogram baseball is thrown straight up into the air with an initial velocity of 20 meters per second. As the ball rises to its peak height, air resistance is considered negligible. What happens to the ball's energy as it moves from the moment of release to its peak height?

   1. AA. Kinetic energy increases while potential energy remains constant.
   2. BB. Kinetic energy transforms into gravitational potential energy.
   3. CC. Gravitational potential energy transforms into thermal energy.
   4. DD. Potential energy decreases while kinetic energy increases.
   Show answer to question 6

   Answer: B. Kinetic energy transforms into gravitational potential energy.

   As the ball ascends, gravity slows its speed until it momentarily stops at the peak, meaning its kinetic energy decreases to zero. Because total mechanical energy is conserved in the absence of air resistance, the lost kinetic energy is converted into gravitational potential energy. The claim that potential energy decreases while kinetic energy increases describes the ball falling back toward the ground, not rising.

7. Question 7 of 25Hard

   A student sets up four identical potted plants under different combinations of conditions to test the requirements for starch production: - Plant 1: Exposed to light; air with carbon dioxide removed - Plant 2: Kept in darkness; air with normal carbon dioxide - Plant 3: Kept in darkness; air with carbon dioxide removed - Plant 4: Exposed to light; air with normal carbon dioxide After 48 hours, only Plant 4 tests positive for starch in its leaves. Why was it essential to include Plant 4 in this investigation?

   1. AA. To prove that starch forms even when both experimental inputs are absent
   2. BB. To test whether darkness causes carbohydrates to break down more rapidly
   3. CC. To serve as a positive control showing starch production under normal conditions
   4. DD. To verify that removing carbon dioxide causes permanent damage to leaf tissue
   Show answer to question 7

   Answer: C. To serve as a positive control showing starch production under normal conditions

   Plant 4 acts as a positive control because it receives both normal light and carbon dioxide, confirming that the experimental system and plant species are capable of producing starch under standard conditions. Without Plant 4, the absence of starch in the other plants could have been blamed on unhealthy plants or faulty testing rather than the absence of light or carbon dioxide.

8. Question 8 of 25Easy

   A lichen is a close association between a fungus and an alga. The fungus provides a place to live and helps retain minerals, while the alga photosynthesizes and supplies sugars. Both partners benefit from the association. Which term best classifies this relationship?

   1. AA. Parasitism
   2. BB. Competition
   3. CC. Mutualism
   4. DD. Commensalism
   Show answer to question 8

   Answer: C. Mutualism

   Both the fungus and the alga benefit, so the relationship is mutualism. Commensalism would mean only one partner benefits and the other is unaffected, but here both receive a clear benefit.

9. Question 9 of 25Medium

   A student investigated osmosis by soaking identical potato cylinders in different concentrations of sucrose for two hours. The results are summarized below: - 0.0 M sucrose: +15% mass change - 0.2 M sucrose: +7% mass change - 0.4 M sucrose: -1% mass change - 0.6 M sucrose: -8% mass change - 0.8 M sucrose: -16% mass change Based on these data, what is the best estimate for the internal solute concentration of the potato cells?

   1. AA. Between 0.2 M and 0.4 M
   2. BB. Between 0.0 M and 0.2 M
   3. CC. Greater than 0.8 M
   4. DD. Between 0.4 M and 0.6 M
   Show answer to question 9

   Answer: A. Between 0.2 M and 0.4 M

   The internal solute concentration corresponds to the point where there is no net movement of water, resulting in a 0% change in mass. Because the mass change switches from positive (+7%) to negative (-1%) between 0.2 M and 0.4 M, the zero-change isotonic point must lie in that interval. Selecting between 0.4 M and 0.6 M is incorrect because the tissue is already losing mass in that range, indicating a hypertonic surrounding environment.

10. Question 10 of 25Easy

    In a physics laboratory, a student pulls a wooden block across a flat, frictionless track using a calibrated spring scale. The scale reads a constant pulling force of 6.0 newtons, and the block accelerates at a rate of 3.0 meters per second squared. What is the mass of the wooden block?

    1. AA. 2.0 kilograms
    2. BB. 9.0 kilograms
    3. CC. 0.5 kilograms
    4. DD. 18.0 kilograms
    Show answer to question 10

    Answer: A. 2.0 kilograms

    According to Newton's second law, net force equals mass multiplied by acceleration (F = ma). Rearranging the formula to solve for mass gives mass equals net force divided by acceleration (m = F / a), which is 6.0 newtons divided by 3.0 meters per second squared, resulting in 2.0 kilograms. The value of 0.5 kilograms comes from mistakenly dividing acceleration by force instead of force by acceleration.

11. Question 11 of 25Easy

    In a plant, the allele for purple flowers (P) is dominant to the allele for white flowers (p). A homozygous purple-flowered plant (PP) is crossed with a white-flowered plant (pp). What is expected in the offspring?

    1. AA. Half will have purple and half white flowers.
    2. BB. All will have purple flowers.
    3. CC. All will have white flowers.
    4. DD. Three-fourths will have purple and one-fourth white flowers.
    Show answer to question 11

    Answer: B. All will have purple flowers.

    Every offspring receives P from the PP parent and p from the pp parent, so all are Pp and show the dominant purple trait. A 1:1 ratio would require a heterozygous purple parent, not a homozygous purple parent.

12. Question 12 of 25Medium

    A researcher places an electric heater inside a glass bell jar and removes all the air using a vacuum pump. A digital temperature sensor placed two inches away from the heater, without touching it, records a rapid increase in temperature once the heater is turned on. Which heat transfer process explains how thermal energy reached the sensor?

    1. AA. Radiation, because electromagnetic waves travel across empty space
    2. BB. Advection, because heated particles move in horizontal currents
    3. CC. Convection, because warm air rises away from the heat source
    4. DD. Conduction, because atoms collide across the glass container
    Show answer to question 12

    Answer: A. Radiation, because electromagnetic waves travel across empty space

    Radiation does not require a material medium and can transfer thermal energy through a vacuum via electromagnetic waves. Convection and conduction both require matter to transfer energy, so they cannot operate across the evacuated space inside the bell jar.

13. Question 13 of 25Hard

    A student tests four different motorized carts and records the force, distance, and time for each run: Cart 1 uses 100 newtons over 4 meters in 8 seconds; Cart 2 uses 150 newtons over 2 meters in 3 seconds; Cart 3 uses 200 newtons over 3 meters in 10 seconds; Cart 4 uses 80 newtons over 5 meters in 5 seconds. Which cart operated with the highest power output?

    1. AA. Cart 1
    2. BB. Cart 3
    3. CC. Cart 2
    4. DD. Cart 4
    Show answer to question 13

    Answer: C. Cart 2

    Power equals work divided by time, where work equals force multiplied by distance. Calculating each: Cart 1 produces 50 watts (400 joules / 8 seconds), Cart 2 produces 100 watts (300 joules / 3 seconds), Cart 3 produces 60 watts (600 joules / 10 seconds), and Cart 4 produces 80 watts (400 joules / 5 seconds). Cart 3 is a common trap because it performs the greatest total work (600 joules), but Cart 2 delivers the highest power due to its short running time.

14. Question 14 of 25Easy

    In a grassland, grasshoppers eat grass and field mice eat grass. Hawks eat both grasshoppers and field mice. A drought greatly reduces the grass. Which population is most directly affected first?

    1. AA. Both the grasshopper and mouse populations, because both depend directly on grass
    2. BB. The hawk population, because hawks are at the top of the food chain
    3. CC. The grasshopper population only, because insects cannot store water
    4. DD. Neither consumer population, because consumers do not depend on producers
    Show answer to question 14

    Answer: A. Both the grasshopper and mouse populations, because both depend directly on grass

    Both grasshoppers and mice are primary consumers that feed directly on the grass, so a shortage of grass hits them first. The hawks are affected only indirectly and later, which is why choosing the top predator is the tempting but wrong answer.

15. Question 15 of 25Hard

    Biological energy transfers are governed by the laws of thermodynamics. When one mole of glucose is completely metabolized during aerobic cellular respiration, approximately 2,870 kilojoules (kJ) of potential chemical energy is released. The cell captures roughly 1,150 kJ of this total energy by synthesizing approximately 30 to 32 moles of ATP from ADP and phosphate. The remaining energy cannot be captured in chemical bonds and is dissipated into the surrounding environment as thermal energy (heat). Based on the passage, which statement accurately traces the conservation and transformation of energy during aerobic cellular respiration?

    1. AA. The total chemical energy in glucose is divided into usable chemical energy in ATP and thermal energy released as heat.
    2. BB. The chemical energy stored in ATP exceeds the total amount of potential energy initially present in the glucose molecule.
    3. CC. All the potential chemical energy from glucose is successfully converted into chemical energy stored within ATP.
    4. DD. The energy released as heat is recycled by the cell to produce additional glucose molecules from water and carbon dioxide.
    Show answer to question 15

    Answer: A. The total chemical energy in glucose is divided into usable chemical energy in ATP and thermal energy released as heat.

    The total energy released from glucose breakdown is accounted for by the portion trapped in ATP bonds (usable chemical energy) plus the portion released into the environment as heat (thermal energy). Cellular respiration is not 100 percent efficient, so not all glucose energy ends up in ATP, nor can waste heat be recaptured to synthesize new glucose.

16. Question 16 of 25Easy

    A hydrologist tracks water moving through a coastal watershed. Solar energy warms the ocean surface, causing liquid water to vaporize and enter the air. As the moist air rises and cools over a coastal mountain range, tiny droplets form clouds that eventually release rain over a forest floor. Which sequence correctly traces the movement of water between reservoirs in this system?

    1. AA. Atmospheric reservoir to groundwater reservoir to ocean reservoir
    2. BB. Terrestrial surface reservoir to biosphere reservoir to atmospheric reservoir
    3. CC. Ocean reservoir to atmospheric reservoir to terrestrial surface reservoir
    4. DD. Ocean reservoir to deep lithospheric reservoir to atmospheric reservoir
    Show answer to question 16

    Answer: C. Ocean reservoir to atmospheric reservoir to terrestrial surface reservoir

    Solar energy causes evaporation of ocean water into the atmosphere, which then condenses and falls as precipitation onto the land surface. The sequence moving from the ocean reservoir to the atmospheric reservoir and finally to the terrestrial surface reservoir directly tracks this pathway. The choice tracing movement from the terrestrial surface to the biosphere to the atmosphere describes plant uptake and transpiration rather than ocean evaporation and rainfall.

17. Question 17 of 25Easy

    A geologist observes a layer of loose sand and shell fragments along a coastline. Over millions of years, additional layers accumulate on top of these materials. Which sequence of processes will transform these loose sediments into a solid sedimentary rock?

    1. AA. Intense heating and plastic deformation
    2. BB. Melting followed by rapid cooling
    3. CC. Compaction and mineral cementation
    4. DD. Uplift followed by chemical weathering
    Show answer to question 17

    Answer: C. Compaction and mineral cementation

    Sedimentary rocks form through lithification, where accumulating layers exert pressure to compact loose sediments, and dissolved minerals precipitate out of water to cement the particles together. Melting followed by rapid cooling produces igneous rock, not sedimentary rock.

18. Question 18 of 25Medium

    A study reports that people who carry a cigarette lighter are more likely to develop lung cancer than people who do not carry one. Which explanation for this link is most likely?

    1. AA. Lung cancer makes people start carrying lighters.
    2. BB. Smoking is linked to both lighters and cancer.
    3. CC. Lighter use directly damages the lungs over time.
    4. DD. People who avoid lighters are healthier overall.
    Show answer to question 18

    Answer: B. Smoking is linked to both lighters and cancer.

    Smoking is a confounding variable: it is associated with carrying a lighter and is a well-established cause of lung cancer, so it can create an apparent link between lighters and cancer. A lighter itself does not expose the lungs to carcinogens. The idea that cancer leads people to buy lighters reverses the likely direction of events.

19. Question 19 of 25Hard

    A geologist analyzes two rock columns from the same region. Column 1: Top layer: Siltstone containing Fossil C Middle layer: Sandstone containing Fossil B Bottom layer: Shale containing Fossil A Column 2: Top layer: Limestone containing Fossil D Middle layer: Siltstone containing Fossil C Bottom layer: Shale containing Fossil A (Sandstone with Fossil B is absent due to erosion) Assuming neither rock sequence has been overturned, what is the correct chronological sequence of these fossils from oldest to youngest?

    1. AA. Fossil B, Fossil A, Fossil C, Fossil D
    2. BB. Fossil D, Fossil C, Fossil B, Fossil A
    3. CC. Fossil A, Fossil C, Fossil B, Fossil D
    4. DD. Fossil A, Fossil B, Fossil C, Fossil D
    Show answer to question 19

    Answer: D. Fossil A, Fossil B, Fossil C, Fossil D

    In Column 1, the law of superposition establishes that Fossil A is older than Fossil B, which is older than Fossil C. In Column 2, Fossil D appears directly above Fossil C, indicating that Fossil D is the youngest of all, while erosion accounts for the missing layer containing Fossil B. Listing the fossils in reverse order incorrectly treats the topmost, youngest layers as the oldest, violating basic stratigraphic principles.

20. Question 20 of 25Medium

    Cart A (2.0 kg, moving east at 3.0 m/s) collides with cart B (3.0 kg, moving west at 2.0 m/s) on a frictionless track, and they stick together. What is the total momentum of the system before the collision, and what happens to that total momentum?

    1. AA. 12 kg m/s east; the total momentum stays 12 kg m/s east after the collision.
    2. BB. 0 kg m/s; the total momentum becomes 6 kg m/s east after the collision.
    3. CC. 6 kg m/s east; the total momentum drops to half after the collision.
    4. DD. 0 kg m/s; the total momentum stays 0 kg m/s after the collision.
    Show answer to question 20

    Answer: D. 0 kg m/s; the total momentum stays 0 kg m/s after the collision.

    Momentum is a vector, so cart B's westward momentum subtracts from cart A's eastward momentum: 6 kg m/s east plus 6 kg m/s west gives a total of zero. Because total momentum is conserved in the collision, the stuck-together carts must also have zero total momentum, meaning they are at rest. Adding the two sizes to get 12 kg m/s ignores the opposite directions.

21. Question 21 of 25Medium

    In a reaction, breaking the bonds in the reactants requires 600 kJ, and forming the bonds in the products releases 450 kJ. Which statement describes the overall energy change?

    1. AA. The reaction releases 150 kJ and is exothermic.
    2. BB. The reaction absorbs 150 kJ and is endothermic.
    3. CC. The reaction absorbs 1,050 kJ and is endothermic.
    4. DD. The reaction releases 1,050 kJ and is exothermic.
    Show answer to question 21

    Answer: B. The reaction absorbs 150 kJ and is endothermic.

    More energy is needed to break the reactant bonds (600 kJ) than is released when product bonds form (450 kJ). The net difference is 150 kJ absorbed, so the reaction is endothermic. Subtracting in the other order or adding the two values would give the wrong sign or amount.

22. Question 22 of 25Medium

    Which statement best describes how the nucleus and ribosomes work together in a cell?

    1. AA. The nucleus supplies energy for protein building, and ribosomes break proteins apart.
    2. BB. The nucleus builds proteins, and ribosomes store the instructions for making them.
    3. CC. The nucleus packages proteins into vesicles, and ribosomes carry them to the membrane.
    4. DD. The nucleus stores instructions for making proteins, and ribosomes use them to build proteins.
    Show answer to question 22

    Answer: D. The nucleus stores instructions for making proteins, and ribosomes use them to build proteins.

    DNA in the nucleus carries the coded instructions for proteins, and ribosomes are the structures where amino acids are joined into proteins. The option that reverses these roles confuses where the instructions are kept with where the building happens.

23. Question 23 of 25Medium

    A student measures four waves traveling in the same medium. Wave P: frequency 100 Hz, wavelength 3.0 m. Wave Q: frequency 150 Hz, wavelength 2.0 m. Wave R: frequency 200 Hz, wavelength 1.5 m. Wave S: frequency 250 Hz, wavelength 1.0 m. Which wave has a speed different from the others?

    1. AA. Wave S
    2. BB. Wave P
    3. CC. Wave R
    4. DD. Wave Q
    Show answer to question 23

    Answer: A. Wave S

    Multiplying frequency by wavelength gives 300 m/s for waves P, Q, and R, but 250 m/s for wave S, so wave S is the one with a different speed. The highest frequency alone does not determine speed, because wavelength also changes.

24. Question 24 of 25Medium

    Why is an energy pyramid usually widest at the bottom?

    1. AA. Decomposers store most of the energy at the base of the pyramid
    2. BB. Higher trophic levels contain more individuals than lower levels
    3. CC. Predators are larger than their prey at every trophic level
    4. DD. Producers capture the most energy, and higher levels receive less
    Show answer to question 24

    Answer: D. Producers capture the most energy, and higher levels receive less

    An energy pyramid is widest at the bottom because producers contain the most energy and each consumer level receives only part of that energy. Larger predator size or more individuals at higher levels does not explain the pyramid's shape.

25. Question 25 of 25Hard

    A botanist hypothesizes that a newly developed fungal root treatment increases drought tolerance in corn seedlings. The botanist inoculates 50 corn seedlings with the fungus and withholds all water for two weeks. At the end of the trial, 42 seedlings survive. The botanist concludes that the fungal treatment successfully protected the seedlings from drought. Which addition to the experiment is most necessary to justify the botanist's conclusion?

    1. AA. A group of 50 uninoculated seedlings that receives normal watering throughout the two weeks
    2. BB. A group of 50 inoculated seedlings grown with double the standard amount of fertilizer
    3. CC. A group of 50 uninoculated seedlings that has all water withheld for the same two weeks
    4. DD. A group of 50 inoculated seedlings kept in an environment with freezing temperatures
    Show answer to question 25

    Answer: C. A group of 50 uninoculated seedlings that has all water withheld for the same two weeks

    To demonstrate that the fungal treatment improved survival during a drought, the researcher must compare the treated group to an untreated control group exposed to the exact same drought conditions. Without an uninoculated group deprived of water, it is impossible to determine whether 42 out of 50 is an improvement or typical for untreated corn seedlings. Testing untreated seedlings with normal watering would show standard growth, but it would not reveal how untreated seedlings fare when water is withheld.

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