GED Science Practice Test

GED Science Practice Test

Get ready for test day with a GED Science practice test (answers at the end of the post).

This practice set covers questions from all three GED Science subject areas:

  • Physical Science
  • Earth and Space Science
  • Life Science
    Need more practice? Try this GED Science practice test from GED Testing Service (clink on the Science link on the right sidebar to download). You should also check out our top tips for GED science success to get yourself prepped to achieve your best score.

    GED Science Practice Test

    Questions 1-3 are based on the following information and diagram.

    Genes come in pairs—one inherited from each parent. The genes for most traits are either dominant or recessive. If one of the two genes for a trait is dominant, the dominant trait is the one that will be expressed. A recessive gene may be present but will remain hidden if paired with a dominant gene. The only way for a recessive trait to be expressed is if both genes in a pair are recessive.

    Dominant genes are represented by capital letters, and recessive genes are represented by lower case letters. An organism who has two matching genes for a trait (AA or aa) is called homozygous. An organism with non-matching genes for a trait (Aa) is called heterozygous.

    Punnett squares are used to show the possible combinations for traits of the offspring when parent organisms breed. Gregor Mendel studied genetic inheritance in pea plants. The flowers of pea plants could be either purple or white. The Punnett square below shows what happens when two heterozygous purple flowers cross with one another. B represents the dominant purple gene and b represents the recessive white gene.

    GED Science Practice Test: Pea plant punnett square- Magoosh
    Image by Madprime.

    1. According to this Punnett square, the likelihood that the offspring will be purple is

    A) 25%
    B) 50%
    C) 75%
    D) 100%

    2. If just one of these parent pea plants were homozygous instead of heterozygous, the chances of the offspring being white would ________.

    A) increase.
    B) decrease.
    C) stay the same.
    D) Not enough information given.

    3. Brown eyes are dominant and blue eyes are recessive. Someone who has blue eyes must be ________ for that trait.

    A) homozygous
    B) heterozygous

    Questions 4-6 are based on the following information and diagram.

    The moon takes 28 days to revolve around Earth. This period is known as a lunar cycle. As the moon and Earth change position relative to one another and to the sun, the moon appears differently when viewed from Earth. The moon emits no light of its own, so “moonlight” is actually the sun’s light reflecting off of the moon’s surface. Depending on how the sunlight hits it at different times, the moon looks very different from Earth throughout the lunar cycle. These changes are known as the phases of the moon.

    GED Science Practice Test: Phases of the Moon- Magoosh
    Image by Andonee.

    4. During a new moon,

    A) sunlight does not hit the surface of the moon.
    B) the moon appears fully lit from Earth.
    C) the lighted side of the moon is not visible from Earth.
    D) the moon is at its closest point to Earth.

    5. Waning occurs when a moon is changing from a ______ to a _______ moon.

    A) full; new
    B) new; full

    6. The length of a lunar cycle is based on

    A) the moon’s rotation on its axis.
    B) the Earth’s rotation on its axis.
    C) the Earth’s orbit around the sun.
    D) the moon’s orbit around the Earth.

    Questions 7-10 are based on the following information and diagram.

    The periodic table lists all of the known elements. The elements are listed in order of atomic number, from least to greatest. An element’s atomic number (shown in the upper left corner of each element on the periodic table below) is equal to the number of protons in one atom of that element. The periodic table also lists the element’s atomic weight, which is approximately equal to the sum of the number of protons and neutrons in one atom of the element, since the weight of electrons is considered negligible. The number of electrons and the number of protons in an atom are equal.

    GED Science Practice Test: periodic table- Magoosh

    7. How many protons are in an atom of gold?

    8. Which of these has the largest atomic mass?

    A) Carbon
    B) Helium
    C) Nitrogen
    D) Sodium

    9. Which of these elements has fewer electrons than boron?

    A) Oxygen
    B) Sodium
    C) Helium
    D) Neon

    10. An atom of beryllium (Be) contains how many neutrons?

    Questions 11- 12 are based on the information and diagram below.

    A food chain describes the transfer of energy through an ecosystem. Plants are called producers because they make their own food using the photosynthesis. Organisms get their energy by eating other organisms are known as consumers. Consumers in a food chain are leveled (i.e., primary consumer, secondary consumer, etc.).

    GED Science Practice Test: Food-chain- Magoosh
    Image by Siyavula Education

    11. In the diagram, which organism is the primary consumer?

    12. Which statement is true based on the diagram?

    A) The mouse receives energy from the owl.
    B) The grasshopper is a source of energy for the grass.
    C) The grass provides energy for the grasshopper.
    D) The owl provides energy for the mouse.

    Questions 13-15 are based on the following diagrams, which show the sources of electricity generation for the states of Maine and Washington, respectively, in 2014.

    GED Science Practice Test: Electricity- Magoosh
    Maine and Washington images by Plazak.

    13. Maine and Washington’s percentages of electricity generation are MOST comparable for

    A) biomass.
    B) hydroelectricity.
    C) natural gas.
    D) wind.

    14. The largest percentage of Washington’s electricity comes from

    A) a fossil fuel.
    B) water.
    C) organic matter.
    D) radioactive materials.

    15. Which of these does Maine rely on more heavily than Washington does?

    A) Hydroelectricity
    B) Biomass
    C) Coal
    D) Nuclear

    Answer Key

    1. C
    Three out of the four possible offspring display the purple trait, which is 75%.

    2. D
    Not enough information is given. The answer depends on whether the homozygous parent plant is purple (BB) or white (bb). If it is purple (BB), crossing it with the heterozygous plant (Bb) would result in BB, BB, Bb, or Bb, all of which would present as purple, lowering the chances of a white offspring to 0%. If, however, the homozygous parent plant was white (bb), a cross with the Bb plant would result in either Bb, Bb, bb, or bb, increasing the chances of getting a white offspring to 50% (up from the original 25%).

    3. A
    In order for a recessive trait to show, both genes in a pair must be recessive. If both genes match, it is called homozygous.

    4. C
    A new moon occurs when the sun lights the side of the moon that faces away from Earth. From Earth’s surface, the lighted side cannot be seen.

    5. A
    Waning means to get smaller. The moon is said to be waning as it moves from a full moon through the gibbous, quarter, and crescent stages to a new moon. When the cycle begins again and the new moon moves through the stages back towards a full moon, it is known as waxing, which means getting bigger.

    6. D
    The lunar cycle is 28 days long, which is the length of time it takes for the moon to orbit around the Earth.

    7. 79
    Gold (Au) has an atomic number of 79, which is equal to its number of protons.

    8. D
    Sodium (Na) has a mass of 22.989 AMU, which is larger than the other elements listed.

    9. C
    Atoms have an equal number of protons and electrons, so the number of electrons in an atom is equal to its atomic number. Boron (B) has 5 electrons. The only choice that has fewer than 5 electrons is helium (He), which has 2.

    10. 5
    Beryllium (Be) has an atomic number of 4, which means it has 4 protons. It has an atomic mass of about 9 AMU. Atomic mass is roughly equal to the sum of the number of protons and the number of neutrons. Subtract the protons from the mass to find the number of neutrons. 9-4=5, so beryllium has 5 neutrons.

    11. Grasshopper
    The grasshopper is the first consumer—the one that eats the producer (in this case, the grass). This is called a primary consumer.

    12. C
    The grasshopper gets energy by eating the grass.

    13. D
    Wind is responsible for 6.1% of Maine’s electricity generation and 5.7% of Washington’s. This is the closest of any two sources.

    14. B
    76.6% of Washington’s electricity comes from hydroelectric power, which harnesses water to generate electricity.

    15. B
    22.3% of Maine’s electricity comes from biomass, whereas only 1.4% of Washington’s electricity does. In all of the other listed sources, Washington has a higher percentage than Maine.