GED Science Practice Test 2025 [Timed 90 minutes – 35 Questions]

Question 1 refers to the following photograph and chart.

Hurricanes such as the one pictured above gather strength as they pass over warm water. According to the chart above, over which of the following bodies of water would a hurricane gather the most strength?

Blood is made up of two main elements: (1) plasma, which is largely water and proteins, and (2) the solid components of blood—red blood cells, white cells, and platelets (important for forming clots). If a patient has lost a lot of blood, he or she may receive a transfusion of “whole blood,” which includes red blood cells and plasma. However, sometimes the patient needs only an increase in the volume of liquid in the bloodstream, in which case plasma alone may be substituted.

A person must be tested for blood type before receiving certain kinds of transfusions because of differences in the ways that red blood cells react to one another. Under what conditions would such testing be necessary?

Questions 3 through 5 are based on the following information.

Coal is formed from the material of plants and other organisms that lived on land and whose remains were covered by mud, which later became rock. Coal is classified by carbon content.

Peat = The remains of plants and organisms that,
because they were covered in bogs, were
prevented by a lack of oxygen from completely
decaying. Still a porous, soft brown mass, peat
has a carbon content of 52%–60%.

Lignite = In time, peat turns into lignite, a soft coal-like
substance that is 60%–65% carbon.

Subbituminous coal = With more time, heat, and pressure, lignite
changes into subbituminous coal, which is about
65%–75% carbon.

Bituminous coal = After even more heat and pressure,
subbituminous coal turns into bituminous coal
with a carbon level of 75%–85%.

Anthracite = This is bituminous coal subjected to another
million years of heat and pressure. Anthracite
has a carbon level of 85%–95% and will burn
only at extremely high temperatures.

A researcher analyzes a piece of coal and finds that it is unusually dense and burns only when subjected to very intense heat. What is the lowest percentage of carbon that this coal is likely to contain?

Enter the _____ %.

Questions 3 through 5 are based on the following information.

Coal is formed from the material of plants and other organisms that lived on land and whose remains were covered by mud, which later became rock. Coal is classified by carbon content.

Peat = The remains of plants and organisms that,
because they were covered in bogs, were
prevented by a lack of oxygen from completely
decaying. Still a porous, soft brown mass, peat
has a carbon content of 52%–60%.

Lignite = In time, peat turns into lignite, a soft coal-like
substance that is 60%–65% carbon.

Subbituminous coal = With more time, heat, and pressure, lignite
changes into subbituminous coal, which is about
65%–75% carbon.

Bituminous coal = After even more heat and pressure,
subbituminous coal turns into bituminous coal
with a carbon level of 75%–85%.

Anthracite = This is bituminous coal subjected to another
million years of heat and pressure. Anthracite
has a carbon level of 85%–95% and will burn
only at extremely high temperatures.

Steel is made in a process in which iron is combined with carbon at extremely high temperatures. Which of the following types of coal might be most useful in this process?

Questions 3 through 5 are based on the following information.

Coal is formed from the material of plants and other organisms that lived on land and whose remains were covered by mud, which later became rock. Coal is classified by carbon content.

Peat = The remains of plants and organisms that,
because they were covered in bogs, were
prevented by a lack of oxygen from completely
decaying. Still a porous, soft brown mass, peat
has a carbon content of 52%–60%.

Lignite = In time, peat turns into lignite, a soft coal-like
substance that is 60%–65% carbon.

Subbituminous coal = With more time, heat, and pressure, lignite
changes into subbituminous coal, which is about
65%–75% carbon.

Bituminous coal = After even more heat and pressure,
subbituminous coal turns into bituminous coal
with a carbon level of 75%–85%.

Anthracite = This is bituminous coal subjected to another
million years of heat and pressure. Anthracite
has a carbon level of 85%–95% and will burn
only at extremely high temperatures.

Steel is made in a process in which iron is combined with carbon at extremely high temperatures. Which of the following types of coal might be most useful in this process?

Drag and drop the appropriate type of coal into each box. (For this practice test, select the appropriate letter in the following option)

Questions 6 and 7 are based on the following information.

Most seeds will germinate when they have moisture, oxygen, and the right temperature, but different seeds need differing proportions of each of these ingredients. Most seeds require a temperature of between 15 degrees and 27 degrees centigrade to germinate, although some seeds, such as the maple, can germinate in far colder climates, and some other seeds, such as corn, require warmer temperatures. Before germination, seeds must absorb water, but too much absorption of water will encourage the growth of fungus, which can halt the germination process.

Which of the following environments would be most suitable for the germination of corn seeds?

Questions 6 and 7 are based on the following information.

Most seeds will germinate when they have moisture, oxygen, and the right temperature, but different seeds need differing proportions of each of these ingredients. Most seeds require a temperature of between 15 degrees and 27 degrees centigrade to germinate, although some seeds, such as the maple, can germinate in far colder climates, and some other seeds, such as corn, require warmer temperatures. Before germination, seeds must absorb water, but too much absorption of water will encourage the growth of fungus, which can halt the germination process.

Based on the information in the passage, which of the following is most likely true?

During periods of intense activity, the cells of the body need more oxygen than the body is supplying, a situation known as oxygen debt. During these periods, the body’s cells briefly switch to “anaerobic respiration,” which produces lactic acid. The buildup of lactic acid in the tissues signals the brain to increase breathing and heart rates, thus supplying the body with more oxygen.

After which of the following activities would lactic acid most likely be found in the body?

During periods that are unfavorable for growth, some plants become dormant. Woody plants are protected during such periods by their bark. Perennial plants die above ground, but their roots remain alive. Annual plants die, but their seeds survive to continue the life of the species.

Which of the following would most likely be a time of year during which plants might lie dormant?

Question 10 refers to the following diagram.

The diagram above shows various layers of rock that have been deposited over time. Drag and drop the rock layers into the appropriate boxes. (For this practice test, select the letters in the choices.)

Question 11 refers to the following diagram.

Which of the following conclusions is most likely to be true regarding the food chain above?

10. Passive protection is a method by which organisms protect themselves from predators, not by fighting, but by their appearance, smell, or sound. Protective resemblance is a type of passive protection in which an animal’s coloring mimics the natural environment, acting as a kind of camouflage. Protective mimicry is another type of passive protection in which a defenseless organism resembles a more powerful organism. Another interesting example of passive protection is the Monarch butterfly, which smells and tastes so bad to other organisms that virtually no other animal or insect will eat it.

Which of the following is NOT an example of passive protection?

The density of seawater is 1,029 kilograms/meter³. 1 kilogram/liter = 1,000 kilograms/meter³. What is the density of seawater in kilograms/liter? (You may use a calculator.)

Question 14 refers to the following scenario

Researchers in a particular city theorize that decreasing the greenhouse gas emissions in that city will result in better respiratory health for its citizens. In order to test this theory, they institute two programs. The first program provides commuters with financial incentives to take public transportation, and the second program initiates a respiratory care education campaign and provides free clinics for citizens suffering from respiratory health issues.

During the five years after the researchers institute the two programs, greenhouse gas emissions in the city decrease by 50%, and a citywide survey reveals that cases of illness due to respiratory problems have decreased by 65%. Researchers therefore conclude that their theory was correct: Decreasing greenhouse gas emissions resulted in better respiratory health for local citizens.

Which of the following best shows why the researchers’ conclusion is flawed?

Lobsters are crustaceans commonly found in the waters of the Atlantic Ocean off the North American coast between Maine and North Carolina. Researchers studied the weights of these creatures over a period of a few years. Some of the results are displayed in the table below.

The researchers hope to find the most commonly occurring lobster weight for the lobsters studied during the five-year period shown above.

The researchers must calculate the ______ of the weights, which is_______

You may use a calculator.

Amy tracks the monthly snowfall in two areas over a period of several months. One area is a region of high elevation, and the other is an area of low elevation. The table below displays her results.

What is the mean of the data shown in the table?

You may use a calculator.

Scientists calculate the pressure within a gas by using the following equation:

In the equation:

P is the pressure of the gas;
N is the number of particles in the gas;
k is a constant;
T is the temperature of the gas;
V is the volume of the gas

If the number of particles in the gas decreases, which of the following changes will result in an increase in the pressure of the gas?

There are four basic types of chemical reactions, as shown in the table below

The balanced chemical equation describing the reaction between hydrogen and fluorine is shown below.

H₂ + F₂ → 2HF

Which of the four basic types of chemical reactions is this?

Question 19 refers to the following graph.

According to the chart above, which of the following regions had the largest projected increase in the number of AIDS deaths between 2011 and 2020?

Scientists classify stars according to the following categories: O, B, A, F, G, K, M. A star’s category depends upon its spectral type, which is determined by its temperature. The chart below shows five stars of different categories, along with their temperatures.

However, rather than measuring star temperature in degrees Fahrenheit, scientists typically measure star temperature in units of Kelvin. The conversion from Kelvin to Fahrenheit is given by the following formula:

What is the approximate temperature of the A-type star in Kelvin?
You may use a calculator.

Questions 21 and 22 refer to the following graph.

According to the information above, which of the following statements is true?

Questions 21 and 22 refer to the following graph.

Select the point on the graph that would be of the most importance in foretelling an earthquake in Nicaragua. (Select an X in the Drop-Down section for this practice test.)

21. or years, paleontologists have debated whether the archaeopteryx, a creature that lived 150 million years ago, was an early species of bird or a dinosaur that spent most of its time on the ground. Its feathers and wings were of only limited use, they say, and could not sustain flight.

Ornithologists, on the other hand, believe that archaeopteryx was first and foremost a bird. As evidence, they point to fossil remains of the creature that show its claws were curved so that it could perch on tree limbs. Curved claws would have prevented the animal from walking or running quickly on the ground.

According to paleontologists, the archaeopteryx was incapable of:

21. or years, paleontologists have debated whether the archaeopteryx, a creature that lived 150 million years ago, was an early species of bird or a dinosaur that spent most of its time on the ground. Its feathers and wings were of only limited use, they say, and could not sustain flight.

Ornithologists, on the other hand, believe that archaeopteryx was first and foremost a bird. As evidence, they point to fossil remains of the creature that show its claws were curved so that it could perch on tree limbs. Curved claws would have prevented the animal from walking or running quickly on the ground.

According to the theory advanced by ornithologists, which of the following is most likely to have been a modern-day descendant of the archaeopteryx?

24. In science, work is defined as the component of force parallel to motion multiplied by displacement. One reason that individuals use ramps, rather than lifting heavy items straight up, is that using a ramp increases total displacement but reduces the amount of force required to move an object by exactly the same amount as the increase in displacement, provided that the ramp’s surface is frictionless.

According to the information in the paragraph, using a ramp with a frictionless surface will have which of the following effects?

Below is a table listing the concentrations of chemicals found in human blood and urine.

Based on the table above, which of the following chemicals is NOT normally found in urine?

In a certain forest, foxes prey on rabbits. A virus that infects only rabbits spreads through the forest, killing many rabbits.

Which of the following is most likely to occur to the fox population?

A solar eclipse is a celestial event during which the sun appears partially or totally obstructed when viewed from a certain location on Earth. The diagram below shows a solar eclipse.

Based on the information above, which of the following is mostly likely to be true during a solar eclipse?

Questions 29 and 30 refer to the following passage.

Pathogenic microbes, microorganisms that cause disease, include viruses, bacteria, fungi, and protozoa. Such microbes can invade hosts through several pathways, including through the air, through direct or indirect physical contact, through blood, and through other bodily fluids.

Medical researchers are currently attempting to find better treatments for microbial diseases by developing new pharmaceuticals. Currently, many doctors prescribe penicillin, which is derived from the spores of a fungus and which prevents the growth of new bacteria, to treat bacteria-induced microbial diseases, and antiviral compounds to combat viruses. However, such treatments do not always eradicate the relevant diseases, and while some microbe-induced illnesses, such as chickenpox, may not be life-threatening, others, such as those that cause Ebola, can be deadly.

Below is a chart of some common microbe-induced illnesses and their causes.

Which of the following is most likely treatable with penicillin?

Questions 29 and 30 refer to the following passage.

Pathogenic microbes, microorganisms that cause disease, include viruses, bacteria, fungi, and protozoa. Such microbes can invade hosts through several pathways, including through the air, through direct or indirect physical contact, through blood, and through other bodily fluids.

Medical researchers are currently attempting to find better treatments for microbial diseases by developing new pharmaceuticals. Currently, many doctors prescribe penicillin, which is derived from the spores of a fungus and which prevents the growth of new bacteria, to treat bacteria-induced microbial diseases, and antiviral compounds to combat viruses. However, such treatments do not always eradicate the relevant diseases, and while some microbe-induced illnesses, such as chickenpox, may not be life-threatening, others, such as those that cause Ebola, can be deadly.

Below is a chart of some common microbe-induced illnesses and their causes.

Medical researchers fear that preventing those suffering from microbial diseases from having physical contact with others may not be sufficient to stop the spread of such diseases. Which of the following quotes from the passage supports this idea?

Questions 31 and 32 refer to the following passage.

Hereditary traits are encoded by genes that are located on chromosomes. Chromosomes come in pairs, and the pair of genes for a particular feature determines the characteristics of that trait. In many cases, genes exhibit a pattern called classical dominance. In such cases, the gene for a dominant trait is always expressed when present. An individual may have only a dominant gene and have two copies of that gene, or an individual may be hybrid and have one dominant gene and one recessive gene. In hybrids, the dominant gene hides the expression of the recessive gene. A recessive gene is expressed only when both copies of the gene are recessive.

In literature, dominant genes are represented by capital letters, while recessive genes are represented by lowercase letters.

In pea plants, pea color is a hereditary trait. Green comes from a dominant gene, and yellow comes from a recessive gene, so that if a plant has one gene for green and one gene for yellow, that plant will produce green peas.

The following Punnett Square shows the results when two hybrid pea plants produce new plants. Punnett Squares predict the likelihood of a specific gene combination occurring. Approximately 75% of the offspring in this case are green, and the rest are yellow.

Which of the following is the best explanation for the results displayed in this Punnett Square?

Questions 31 and 32 refer to the following passage.

Hereditary traits are encoded by genes that are located on chromosomes. Chromosomes come in pairs, and the pair of genes for a particular feature determines the characteristics of that trait. In many cases, genes exhibit a pattern called classical dominance. In such cases, the gene for a dominant trait is always expressed when present. An individual may have only a dominant gene and have two copies of that gene, or an individual may be hybrid and have one dominant gene and one recessive gene. In hybrids, the dominant gene hides the expression of the recessive gene. A recessive gene is expressed only when both copies of the gene are recessive.

In literature, dominant genes are represented by capital letters, while recessive genes are represented by lowercase letters.

In pea plants, pea color is a hereditary trait. Green comes from a dominant gene, and yellow comes from a recessive gene, so that if a plant has one gene for green and one gene for yellow, that plant will produce green peas.

The following Punnett Square shows the results when two hybrid pea plants produce new plants. Punnett Squares predict the likelihood of a specific gene combination occurring. Approximately 75% of the offspring in this case are green, and the rest are yellow.

Dimples result from a dominant gene, and a lack of dimples results from a recessive gene. Based on the information in the passage, which of the following will be true for an individual who is a hybrid?

Questions 33 and 34 refer to the following graph.

The graph below shows a science experiment in which a sample of ice at −20 degrees C is heated to 120 degrees C. During the experiment, the ice melted into water and then the water boiled and turned into steam.

Based on the information presented above, which of the following statements is most accurate?

Questions 33 and 34 refer to the following graph.

The graph below shows a science experiment in which a sample of ice at −20 degrees C is heated to 120 degrees C. During the experiment, the ice melted into water and then the water boiled and turned into steam.

Select the area on the graph during which the entire sample consists of liquid water. (For this practice test, write an X from the drop-down.)

33. Bees are insects that play an important role in any ecosystem that has flowering plants. Bees serve as primary pollinators and enable flowering plants to reproduce. Scientists estimate that nearly one-third of the human food supply consists of plants that depend on bees for pollination.

Based on the information above, which characteristic of bees is most important to an ecosystem?