By Murray Shukyn, Dale E. Shuttleworth, Achim K. Krull

The GED Science test will seek to ask questions that evaluate your understanding of basic science concepts. You will encounter short readings followed by questions. Read the questions carefully and work at a steady pace.

Sample questions

Give these sample questions a try to see how you will do on test day.

Passage A

Climate change, along with habitat destruction and pollution, is one of the important stressors that can contribute to species extinction. The IPCC estimates that 20–30% of the plant and animal species evaluated so far in climate change studies are at risk of extinction if temperatures reach levels projected to occur by the end of this century.

Projected rates of species extinctions are 10 times greater than recently observed global average rates and 10,000 times greater than rates observed in the distant past (as recorded in fossils).

  1. One of the great dangers to the earth as a result of climate change is the ________ of species.

Passage B

[W]hen coral reefs become stressed, they expel microorganisms that live within their tissues and are essential to their health. This is known as coral bleaching. As ocean temperatures warm and the acidity of the ocean increases, bleaching and coral die-offs are likely to become more frequent. Chronically stressed coral reefs are less likely to recover.

  1. Coral bleaching refers to

    • (A) chemical reaction between the ocean waters and microorganisms in the coral

    • (B) expulsion of microorganisms from within coral reefs

    • (C) the effect of extremely strong sunlight on coral reefs

    • (D) not enough information

Passage C

For many species, the climate where they live or spend part of the year influences key stages of their annual life cycle, such as migration, blooming, and mating. As the climate has warmed in recent decades, the timing of these events has changed in some parts of the country. Some examples are:

  • Warmer springs have led to earlier nesting for 28 migratory bird species on the East Coast of the United States.

  • Northeastern birds that winter in the southern United States are returning north in the spring 13 days earlier than they did in the early 20th century.

  • In a California study, 16 out of 23 butterfly species shifted their migration timing and arrived earlier.

Changes like these can lead to mismatches in the timing of migration, breeding, and food availability. Growth and survival are reduced when migrants arrive at a location before or after food sources are present.

  1. Severe climate changes can lead to extinction of a species though ________ in aspects of their lives upon which their survival depends.

Passage D

New remote sensing technologies are empowering scientists to measure and understand subtle changes in the Earth’s surface and interior that reflect the response of the Earth to both the internal forces that lead to volcanic eruptions, earthquakes, landslides and sea-level change and the climatic forces that sculpt the Earth’s surface.

For instance, InSAR [interferometric synthetic aperture radar] and LiDAR [light detection and ranging] measurements from satellite and airborne sensors are used to provide images of millimeter scale surface changes that indicate an awakening of volcanic activity long before seismic tremors are felt. Ground based geodetic GPS instruments provide time continuous measurements of this activity though they are often lost during intense volcanic activity.

Thermal infrared remote sensing data from NASA satellites signal impending activity by measuring ground temperatures and variations in the composition of lava flows as well as the sulfur dioxide in volcanic plumes. The combination of instruments provide accurate information that can be used for both long term and short hazard assessment.

These same LiDAR, InSAR and thermal instruments also provide accurate information on the velocity of ice steams, sub glacial lake activity, glacial rebound of the Earth’s crust, and the retreat and advance of mountain glaciers that are related to climatic changes.

  1. New remote sensing technologies provide ________ that may lead to long and short-term hazard assessment.

Passage E

By observing galaxies formed billions of years ago, astronomers have been able to paint an increasingly detailed picture of how the universe evolved. According to the widely accepted Big Bang theory, our universe was born in an explosive moment approximately fifteen billion years ago.

All of the universe’s matter and energy — even the fabric of space itself — was compressed into an infinitesimally small volume and then began expanding at an incredible rate. Within minutes, the universe had grown to the size of the solar system and cooled enough so that equal numbers of protons, neutrons, and the simplest atomic nuclei had formed.

  1. Astronomers believe that the universe evolved about _________ billion years ago.


Compare your answers against the answers below.

Passage A

  1. extinction. The passage states that climate change will cause species to become extinct at an accelerated rate.

Passage B

  1. B. expulsion of microorganisms from within coral reefs. Stressed coral reefs expel microorganisms essential to their health. Choice (A) sounds correct if you skim the passage, but it’s incorrect. Choice (C) is also wrong because there’s no mention of the effect of sunlight on the reefs, and Choice (D) is wrong because you have enough information to answer the question.

Passage C

  1. mismatches. These mismatches can lead to dramatic changes in the lives of a species, which could lead to eventual extinction.

Passage D

  1. information. According to the passage, all of the technologies mentioned provide information that may help scientists in assessing the potential for impending hazards.

Passage E

  1. 15. The Big Bang theory says that this series of occurrences took place about 15 billion years ago.