GED: Science

The Science Test is 1 hour and 20 minutes long, and has 50 multiple-choice questions in the following areas:
  • Life Sciences-Biology (45%)

  • Physical Sciences-Physics and Chemistry (35%)

  • Earth and Space Science (20%)

What to Expect

  • Expect questions that test how well you understand major scientific concepts, ideas, and principles.

  • Expect settings that are familiar from everyday life. For example, questions about boiling water in a kitchen or growing flowers in a garden are set in familiar locations.

  • Expect questions on the natural environment, everyday occurrences, and natural phenomena.

  • Expect fewer than half of the questions to come from the life sciences (biology), about a third from the physical sciences (physics and chemistry), and about a fifth from Earth and space science.

  • Expect about half of the questions to ask you to understand information in diagrams, charts, maps, graphs, and tables.

  • Expect some of the questions to be in groups, or sets — that is, two to five questions that refer to the same information, diagram, or chart.

Kinds of Questions

The GED Science Test will test higher-level thinking skills. The exam will not ask you simply to remember facts or basic principles such as the formula for the acceleration of gravity or Einstein's general theory of relativity. However, you are expected to understand important concepts and principles in science.

The questions on the Science Test are grouped as follows:

Comprehension Questions (20%): You should be able to understand the meaning of information presented in readings as well as in maps, diagrams, charts, and graphs. Comprehension questions can be answered simply from the information presented. Comprehension questions will ask

  • What is the main point?

  • What is suggested by the information?

Application Questions (30%): You should be able to reason one step beyond the comprehension level. You must apply information already stated to solve a problem in a different situation. Application questions will ask

  • Can you use given information in a new setting?

  • Can you use suggested information in a new setting?

Analysis Questions (30%): You should be able to understand the important parts of the information given and the relationships between these parts. You must be able to find the methods used to show how ideas are developed. Analysis questions will ask

  • Can you find ideas that are not specifically stated?

  • Can you tell what makes an event happen and what are the results?

  • Can you tell the difference between a fact and a hypothesis?

Evaluation Questions (20%): You should be able to judge the accuracy of stated or assumed material and evaluate its importance. Evaluation questions will ask

  • Can you tell whether the information given would support a point of view?

  • Can you detect why events occur?

  • Can you find why a hypothesis is not correct?

  • Can you predict an outcome?

What You Should Do

Read the information looking for the following key points:

  • What is the main idea?

  • What does the information suggest?

  • Can you see causes and results?

Refer to the information, passage, diagram, chart, graph, or map as often as necessary. Make sure you understand how to read the diagram, chart, graph, or map. Know what information is being presented.

Make sure you understand what the question is asking, for example:

  • Which of the following aspects of cats would a veterinarian consider most important?

  • All the following duties are performed by a male ant except . . .

  • The occurrence of tidal waves in this region indicates . . .

  • Which of the following is the best explanation for . . .

  • Which of the following behaviors is similar to . . .

  • Which of the following has the most value to . . .

  • This relationship would best be classified as . . .

  • Why is it dangerous to . . .

Example Questions

You may be given a comprehension question similar to the question that follows.

  1. During the fertilization of a flower, it is necessary for pollen to reach the central pistil. This fertilization is one mode of sexual reproduction. A male sex cell (pollen) must unite with a female sex cell (ovum within the pistil) to produce a fertile embryo.

    This reproduction requires the contact of two germ cells because

    1. a chemical reaction initiates the fertilization

    2. each contains only half the genetic material

    3. individual cells carry inadequate nutrients

    4. the wind is too erratic for reliable stimulation

    5. vegetable reproduction is by the mechanism of budding

    The right answer is (2). In this question, you are being asked why two germ cells are needed.

    The information given explains that this is a form of sexual reproduction. "A male sex cell (pollen) must unite with a female sex cell (ovum within the pistil) to produce a fertile embryo." So, each sex cell contains only half the chromosomes (the genetic material) that the plant needs.

    You could be given an application question similar to the question that follows.

  2. Corrasion is defined as wind erosion. Corrasion is limited by vegetation (plant cover), snow cover, high rainfall, or lack of wind.

    In which of the following sites would you expect the MOST corrasion?

    1. A desert basin

    2. A mountain range

    3. A prairie grassland

    4. A sheltered valley

    5. A tropical jungle

    The right answer is (1). The desert basin would suffer the most erosion by wind.

    The absence of plant cover and abundance of loose material permit much corrasion. Sand-sized material that is eroded accumulates downwind as dunes.

    You could be given an analysis question similar to this one.

  3. Imagine that Robert is indoors admiring himself in a mirror by the light of a lamp. The light rays that generate such a good self-image have taken a complicated journey.

    Which of the following is the correct sequence of travel for the light?

    1. Bulb-eye-mirror-face

    2. Face-bulb-mirror-eye

    3. Bulb-face-mirror-eye

    4. Mirror-bulb-face-eye

    5. Bulb-mirror-face-eye

    The right answer is (3). To answer this question, you must first decide where this journey begins.

    The source of the light is the bulb. That light reflects from Robert's face and then is reflected again from the mirror. The light finally enters his eye. If you realize that the light begins at the bulb and ends at his eye, you can eliminate choices (1), (2), and (4).

    You might be given an evaluation question similar to this one.

  4. Pure nitrogen is obtained commercially by first liquefying air, which is 78% nitrogen. This liquefying can be accomplished by changing either the temperature or the pressure, or both.

    Which of the following would be the BEST way to condense air to a liquid?

    1. Lowering the temperature very quickly

    2. Lowering the pressure very quickly

    3. Lowering the temperature while raising the pressure

    4. Lowering the pressure while leaving the temperature constant

    5. Raising the temperature

    The right answer is (3). Lowering the temperature can change a gas into a liquid. However, raising the pressure leads to the same result, because it forces the molecules closer together.

    The best procedure would be to lower the temperature of air while you increase the pressure.