GED Science Practice Test Welcome to your GED Science Practice Test 1. GED Science: Life Science Which of the following best describes the role of ribosomes in cellular function? A. Synthesis of lipids and detoxification of substances. B. Packaging of proteins for secretion or use within the cell. C. Conversion of glucose into usable energy in the form of ATP. D. Synthesis of proteins based on the information in messenger RNA. None 2. GED Science: Life Science In plants, which of the following structures is primarily responsible for water and nutrient absorption from the soil? A. Stomata B. Xylem C. Phloem D. Root hairs None 3. GED Science: Life Science Which of the following best explains the significance of the phospholipid bilayer in cell membranes? A. It facilitates the diffusion of gases and small hydrophobic molecules. B. It provides structural support for the cell, preventing it from bursting. C. It acts solely as a barrier to protect the cell from its external environment. D. It actively transports all types of molecules into and out of the cell without energy. None 4. GED Science: Life Science What is the primary function of chlorophyll in photosynthesis? A. It captures light energy and converts it into chemical energy. B. It splits water molecules to release oxygen. C. It synthesizes glucose from carbon dioxide and water. D. It transports glucose to different parts of the plant. None 5. GED Science: Life Science What is the primary function of the mitochondria in eukaryotic cells? A. Synthesis of proteins. B. Photosynthesis. C. Cellular respiration and energy production. D. Storage of genetic material. None 6. GED Science: Life Science Which of the following best describes the principle of competitive exclusion in ecology? A. Two species competing for the same resources cannot coexist if other ecological factors are constant. B. Predator and prey populations fluctuate in response to each other, maintaining ecological balance. C. Symbiotic relationships between species are essential for ecosystem stability. D. Biodiversity increases the resilience of an ecosystem to environmental changes. None 7. GED Science: Life Science Which process describes the movement of water across a semipermeable membrane from an area of lower solute concentration to an area of higher solute concentration? A. Osmosis B. Diffusion C. Active transport D. Endocytosis None 8. GED Science: Life Science What is the significance of the Hardy-Weinberg principle in the study of population genetics? A. It describes how mutation rates affect evolutionary change within populations. B. It provides a model that describes how populations evolve over time. C. It outlines the conditions under which a population's allele frequencies will remain constant. D. It explains the role of genetic drift in small populations. None 9. GED Science: Life Science In the theory of evolution, what mechanism explains the increased prevalence of a heritable trait in a population over time? A. Genetic drift. B. Gene flow. C. Natural selection. D. Bottleneck effect. None 10. GED Science: Life Science In an ecosystem, what term describes the maximum population size of a species that the environment can sustain indefinitely? A. Carrying capacity. B. Ecological footprint. C. Biodiversity index. D. Population equilibrium. None 11. GED Science: Life Science In the carbon cycle, what role do decomposers play? A. They convert atmospheric carbon dioxide into organic carbon. B. They release carbon dioxide back into the atmosphere by breaking down dead organisms and waste products. C. They fix atmospheric carbon dioxide into soil, making it available for plant use. D. They store carbon for long periods in their biomass, reducing atmospheric carbon dioxide levels. None 12. GED Science: Life Science Which of the following best describes the role of enzymes in biochemical reactions? A. They decrease the reaction rate by acting as competitive inhibitors. B. They increase the reaction rate by lowering the activation energy. C. They act as substrates for chemical reactions. D. They permanently change shape after a reaction. None 13. GED Science: Life Science Which of the following best defines a keystone species in an ecosystem? A. A species that is the most abundant in an ecosystem. B. A species that has an exceptionally large biomass in the ecosystem. C. A species whose presence and role within an ecosystem have a disproportionate effect on other organisms within the system. D. A species introduced from another ecosystem that disrupts the native species. None 14. GED Science: Life Science What process do plants use to convert atmospheric nitrogen (N2) into a form that can be absorbed and used for growth? A. Photosynthesis. B. Nitrogen fixation. C. Respiration. D. Transpiration. None 15. GED Science: Life Science Which of the following molecules is primarily responsible for carrying oxygen in the blood of most vertebrates? A. Hemoglobin. B. Chlorophyll. C. Glucose. D. Insulin. None 16. GED Science: Life Science In the Linnaean system of classification, which rank directly follows "Order" in the hierarchy? A. Family. B. Genus. C. Species. D. Class. None 17. GED Science: Life Science In genetics, what is the term used to describe an organism that has two different alleles for a particular trait? A. Homozygous. B. Heterozygous. C. Hemizygous. D. Homologous. None 18. GED Science: Life Science Which cellular structure is responsible for modifying, sorting, and packaging proteins and lipids for secretion or use within the cell? A. Mitochondria B. Golgi apparatus C. Lysosome D. Nucleus None 19. GED Science: Life Science In the context of ecological relationships, what term describes an interaction where one organism benefits and the other is neither harmed nor benefited? A. Mutualism B. Commensalism C. Parasitism D. Amensalism None 20. GED Science: Life Science Which cellular process results in the production of two genetically identical daughter cells from a single parent cell? A. Meiosis. B. Fertilization. C. Mitosis. D. Binary fission. None 21. GED Science: Life Science What is the primary role of the stomata in plant leaves? A. Absorption of nutrients from the soil. B. Capturing light energy for photosynthesis. C. Exchange of gases (CO2 in, O2 out) and transpiration. D. Storage of starch. None 22. GED Science: Life Science Which type of biomolecule is primarily involved in speeding up (catalyzing) chemical reactions in biological organisms? A. Nucleic acids. B. Carbohydrates. C. Lipids. D. Proteins. None 23. GED Science: Life Science Which of the following is a characteristic feature of cancer cells that distinguishes them from normal cells? A. Ability to undergo apoptosis B. Limited number of cell divisions C. Lack of differentiation D. Smaller nucleus None 24. GED Science: Life Science In the nitrogen cycle, what process converts ammonia into nitrite and then into nitrate, making nitrogen available to plants? A. Ammonification B. Nitrification C. Denitrification D. Nitrogen fixation None 25. GED Science: Life Science What is the primary role of cytokines in the immune system? A. To physically capture and engulf pathogens B. To serve as antibodies that neutralize pathogens C. To act as signaling molecules that regulate immune responses D. To directly destroy infected cells and pathogens None 26. GED Science: Life Science What is the primary function of the enzyme Rubisco in photosynthesis? A. Splitting water molecules to release oxygen B. Capturing light energy C. Carbon fixation in the Calvin cycle D. Synthesis of ATP None 27. GED Science: Life Science What term is used to describe a region of an enzyme where the substrate binds and the reaction occurs? A. Active site B. Allosteric site C. Binding domain D. Catalytic core None 28. GED Science: Life Science Which type of cell junctions are primarily responsible for preventing the passage of materials between cells in epithelial tissue? A. Gap junctions B. Desmosomes C. Tight junctions D. Hemidesmosomes None 29. GED Science: Life Science Which principle or law explains the conservation of energy in living systems, particularly how energy is transferred and transformed in biological processes? A. The Law of Segregation B. The First Law of Thermodynamics C. The Law of Independent Assortment D. The Law of Dominance None 30. GED Science: Life Science What type of natural selection results in the favoring of phenotypes at both extremes of the phenotypic range? A. Directional selection B. Stabilizing selection C. Disruptive selection D. Sexual selection None 31. GED Science: Life Science In terms of population genetics, what does the term "gene pool" refer to? A. The total number of genes in a specific population at a given time B. The collection of different alleles in an isolated population C. The total set of genetic information in the gametes of all individuals in a population D. A repository of mutant genes within a species None 32. GED Science: Life Science What is the significance of the discovery of the structure of DNA by Watson and Crick? A. It proved that proteins are the genetic material. B. It led to the development of the first antibiotic. C. It provided the basis for understanding genetic inheritance and mutation. D. It established the role of mitochondria in energy production. None 33. GED Science: Life Science In an ecosystem, which term describes a long-term, stable community that has reached the end of succession? A. Pioneer community B. Climax community C. Secondary community D. Tertiary community None 34. GED Science: Life Science Which organelle is responsible for the breakdown of fatty acids and the detoxification of alcohol in cells? A. Lysosome B. Peroxisome C. Endoplasmic reticulum D. Golgi apparatus None 35. GED Science: Life Science What is the primary mechanism by which antibiotic resistance spreads among bacterial populations? A. Genetic drift B. Conjugation C. Natural selection D. Genetic mutation None 36. GED Science: Life Science What is the primary role of the stomata in plant leaves? A. Absorption of nutrients from the soil. B. Capturing light energy for photosynthesis. C. Exchange of gases (CO2 in, O2 out) and transpiration. D. Storage of starch. None 37. GED Science: Life Science What is the primary ecological role of detritivores in an ecosystem? A. To capture and store solar energy through photosynthesis B. To consume living plants and animals C. To break down dead organic material and recycle nutrients D. To regulate the population sizes of other species through predation None 38. GED Science: Life Science In molecular biology, what process involves the synthesis of a complementary strand of RNA from a DNA template? A. Translation B. Replication C. Transcription D. Reverse transcription None 39. GED Science: Life Science In which phase of mitosis do the chromosomes align at the cell's equatorial plane, ready for separation? A. Prophase B. Metaphase C. Anaphase D. Telophase None 40. GED Science: Earth and Space Science Which layer of the Earth is liquid and responsible for the creation of the Earth's magnetic field? A. Crust B. Mantle C. Outer core D. Inner core None 41. GED Science: Earth and Space Science What phenomenon explains the redshift observed in the light from distant galaxies? A. The Doppler Effect, indicating these galaxies are moving away from us. B. The impact of interstellar dust, which reddens the light. C. The gravitational pull of the Earth bending the light. D. The blue shift, indicating these galaxies are moving towards us. None 42. GED Science: Earth and Space Science In the context of plate tectonics, what is subduction? A. The process where two tectonic plates move away from each other. B. The process where a tectonic plate moves sideways along the boundary of another plate. C. The process where one tectonic plate slides beneath another and is forced into the mantle. D. The process where two tectonic plates collide and rise up to form mountains. None 43. GED Science: Earth and Space Science What is the significance of the Oort Cloud in our solar system? A. It is the primary source of the Earth's meteor showers. B. It is believed to be the source of long-period comets. C. It contains the asteroid belt between Mars and Jupiter. D. It is the region where the Sun's solar wind is stopped by interstellar medium. None 44. GED Science: Earth and Space Science Which of the following best describes the term "albedo" in the context of Earth's climate system? A. The measure of Earth's surface temperature. B. The measure of the Earth's ability to reflect sunlight. C. The amount of carbon dioxide in the Earth's atmosphere. D. The rate at which the Earth's surface absorbs heat. None 45. GED Science: Earth and Space Science What mechanism drives the movement of the Earth's tectonic plates? A. Solar radiation B. Lunar gravitational pull C. Mantle convection D. Magnetic field interactions None 46. GED Science: Earth and Space Science What is the primary reason for the high surface temperatures on Venus? A. Its proximity to the Sun B. Its slow rotational period C. The greenhouse effect caused by its thick atmosphere D. Volcanic activity on its surface None 47. GED Science: Earth and Space Science What does the term "aphelion" refer to in the context of Earth's orbit around the Sun? A. The point at which the Earth is closest to the Sun. B. The point at which the Earth is farthest from the Sun. C. The path the Earth takes as it orbits the Sun. D. The speed at which the Earth orbits the Sun. None 48. GED Science: Earth and Space Science What principle explains why Earth experiences different solar eclipses, such as partial, total, and annular eclipses? A. The variation in the Moon's distance from the Earth due to its elliptical orbit. B. The difference in size between the Sun and the Moon. C. The Earth's rotation on its axis. D. The alignment of the Milky Way galaxy. None 49. GED Science: Earth and Space Science Which of the following is a consequence of the Coriolis effect on Earth? A. The formation of deserts at specific latitudes. B. The deflection of wind and ocean currents. C. The change in the length of days and nights. D. The variation in atmospheric pressure across latitudes. None 50. GED Science: Earth and Space Science How does the theory of plate tectonics explain the distribution of fossil evidence across widely separated continents? A. By suggesting continents move due to solar winds. B. By indicating a worldwide flood that spread species globally. C. By proposing that continents were once connected but have drifted apart. D. By claiming that similar species evolved independently on different continents. None 51. GED Science: Earth and Space Science What is the primary driver of ocean currents? A. The rotation of the Earth on its axis. B. The gravitational pull of the Moon and the Sun. C. Differences in water density and temperature. D. Underwater volcanic activity. None 52. GED Science: Earth and Space Science In terms of geological time scales, what marks the boundary between the Paleozoic and Mesozoic eras? A. The Cambrian Explosion B. The Permian-Triassic Extinction Event C. The Cretaceous-Paleogene Extinction Event D. The Devonian Period None 53. GED Science: Earth and Space Science What does the term "Kepler's Third Law" refer to in the context of planetary motion? A. The planets orbit the Sun in elliptical paths. B. The square of the orbital period of a planet is proportional to the cube of the semi-major axis of its orbit. C. For every action, there is an equal and opposite reaction. D. The orbit of every planet is an ellipse with the Sun at one of the two foci. None 54. GED Science: Earth and Space Science What role do greenhouse gases play in Earth's climate system? A. They reflect sunlight back into space. B. They absorb and emit infrared radiation, warming the Earth's surface. C. They decrease the temperature of the Earth's surface. D. They protect the Earth from harmful solar radiation. None 55. GED Science: Earth and Space Science Which layer of the Earth's atmosphere contains the ozone layer? A. Troposphere B. Stratosphere C. Mesosphere D. Thermosphere None 56. GED Science: Earth and Space Science What is the main reason for the phenomenon of tides on Earth? A. The Earth's rotation on its axis. B. The gravitational pull of the Sun and the Moon on the Earth's oceans. C. Atmospheric pressure changes. D. Thermal expansion of water. None 57. GED Science: Earth and Space Science In the context of the water cycle, what process describes the movement of water from the ground to the atmosphere? A. Condensation B. Precipitation C. Evaporation D. Percolation None 58. GED Science: Earth and Space Science What is the significance of the Chicxulub crater in understanding Earth's history? A. It provides evidence of the Earth's formation. B. It is linked to the extinction of the dinosaurs. C. It marks the impact site of the first artificial satellite. D. It signifies the beginning of the Ice Age. None 59. GED Science: Earth and Space Science What is the primary cause of the Earth's seasons? A. The Earth's distance from the Sun varies throughout the year. B. The tilt of the Earth's rotational axis relative to its orbit around the Sun. C. The varying speed of the Earth's orbit around the Sun. D. The Sun's changing position in the Milky Way galaxy. None 60. GED Science: Physical Science What happens to the resistance in a wire if its length is doubled and its diameter is halved? A. The resistance is halved. B. The resistance is doubled. C. The resistance is quadrupled. D. The resistance remains the same. None 61. GED Science: Physical Science What is the term for the amount of energy required to raise the temperature of 1 gram of water by 1 degree Celsius? A. Joule B. Calorie C. Watt D. Newton None 62. GED Science: Physical Science Which of the following processes is an example of a chemical change? A. Boiling water B. Dissolving sugar in water C. Rusting of iron D. Melting of ice None 63. GED Science: Physical Science Which law explains the behavior of gas when temperature increases at constant volume? A. Boyle's Law B. Charles's Law C. Gay-Lussac's Law D. Avogadro's Law None 64. GED Science: Physical Science In the context of physical science, which element is classified as a noble gas? A. Hydrogen B. Nitrogen C. Argon D. Oxygen None 65. GED Science: Physical Science In an electrical circuit, if the voltage is held constant and the resistance increases, what happens to the current? A. The current increases. B. The current decreases. C. The current remains unchanged. D. The current initially decreases, then increases. None 66. GED Science: Physical Science Which principle explains why a helium balloon rises in the air? A. Pascal's principle B. Archimedes' principle C. Newton's third law of motion D. Boyle's law None 67. GED Science: Physical Science What is the primary force responsible for the formation of chemical bonds? A. Gravitational force B. Electromagnetic force C. Strong nuclear force D. Weak nuclear force None 68. GED Science: Physical Science Which atomic particle is directly involved in chemical reactions? A. Neutron B. Proton C. Electron D. Nucleon None 69. GED Science: Physical Science What is the phenomenon where light bends as it passes from one medium to another called? A. Reflection B. Refraction C. Polarization D. Dispersion None 70. GED Science: Physical Science In a redox reaction, what happens to the element that is oxidized? A. It gains electrons. B. It loses electrons. C. It gains protons. D. It loses protons. None 71. GED Science: Physical Science What principle is demonstrated when a mirror reflects light to form an image? A. Refraction B. Diffraction C. Interference D. Reflection None 72. GED Science: Physical Science Which concept is described by the Second Law of Thermodynamics? A. Energy is conserved within a closed system. B. The total entropy of an isolated system can never decrease over time. C. Temperature remains constant during a phase change. D. Pressure and volume of a gas are inversely proportional at constant temperature. None 73. GED Science: Physical Science What is the name of the phase change from gas to liquid? A. Freezing B. Melting C. Condensation D. Sublimation None 74. GED Science: Physical Science What is the outcome of a displacement reaction between zinc metal and copper sulfate solution? A. Zinc sulfate and copper metal B. Copper and zinc oxide C. Zinc oxide and copper sulfate D. Copper sulfate and zinc chloride None 75. GED Science: Physical Science What property of a wave is directly proportional to its energy? A. Amplitude B. Wavelength C. Speed D. Frequency None 76. GED Science: Physical Science Which of the following describes the Heisenberg Uncertainty Principle? A. It is impossible to determine both the position and velocity of an electron simultaneously with absolute precision. B. The position of an electron in an atom can be precisely determined if its energy level is known. C. The velocity of particles in a gas can be calculated with absolute certainty if the temperature is fixed. D. Electrons orbit the nucleus in predictable paths with known positions and velocities. None 77. GED Science: Physical Science In an exothermic reaction, energy is: A. Absorbed from the surroundings. B. Released into the surroundings. C. Neither absorbed nor released; it remains constant. D. First absorbed, then released, resulting in no net change. None 78. GED Science: Physical Science What type of bond is formed when two atoms share a pair of electrons? A. Ionic bond B. Covalent bond C. Metallic bond D. Hydrogen bond None 79. GED Science: Physical Science In a chemical equation, what does the principle of conservation of mass require? A. The total mass of the reactants equals the total mass of the products. B. The mass of the products is greater than the mass of the reactants. C. The mass of the reactants is greater than the mass of the products. D. Only the number of atoms for each element must be conserved, not the mass. None 80. GED Science: Physical Science The phase change from solid directly to gas is known as: A. Condensation B. Freezing C. Sublimation D. Deposition None 81. GED Science: Physical Science What phenomenon occurs when light waves change direction as they pass from one medium to another, causing an object to appear bent? A. Reflection B. Refraction C. Diffraction D. Interference None 82. GED Science: Physical Science What is the unit of electrical resistance? A. Ampere B. Ohm C. Volt D. Watt None 83. GED Science: Physical Science The principle that states the energy cannot be created or destroyed, only transformed or transferred, is known as: A. The law of conservation of momentum B. The law of conservation of mass C. The law of conservation of energy D. The law of definite proportions None 84. GED Science: Physical Science Which gas law relates the pressure and volume of a gas at constant temperature? A. Charles's Law B. Boyle's Law C. Gay-Lussac's Law D. Avogadro's Law None 85. GED Science: Physical Science What law states that the total pressure exerted by a mixture of gases is equal to the sum of the pressures that each gas would exert if it were alone? A. Charles's Law B. Boyle's Law C. Dalton's Law of Partial Pressures D. Gay-Lussac's Law None 86. GED Science: Physical Science What is the primary force that holds the nucleus of an atom together, despite the repulsive force between protons? A. Electromagnetic force B. Gravitational force C. Strong nuclear force D. Weak nuclear force None 87. GED Science: Physical Science Which of the following is a characteristic property of nonmetals? A. High thermal conductivity B. High electrical conductivity C. High ionization energy D. High ductility None 88. GED Science: Physical Science Which of the following elements has the highest electronegativity? A. Fluorine B. Uranium C. Sodium D. Calcium None 89. GED Science: Physical Science Which principle explains the behavior of a gas when it undergoes an adiabatic compression, assuming no heat is exchanged with the environment? A. Boyle's Law B. Charles's Law C. Gay-Lussac's Law D. The First Law of Thermodynamics None 90. GED Science: Physical Science What phenomenon explains the splitting of white light into its component colors when passing through a prism? A. Reflection B. Refraction C. Diffraction D. Dispersion None 91. GED Science: Physical Science Which atomic model introduced the concept of quantized energy levels for electrons? A. Dalton's atomic model B. Thomson's "plum pudding" model C. Rutherford's nuclear model D. Bohr's model None 92. GED Science: Physical Science In an electrochemical cell, what is the function of the salt bridge? A. To increase the voltage output B. To prevent the mixing of the reactants C. To allow the flow of ions and maintain electrical neutrality D. To act as a physical barrier between the anode and cathode None 93. GED Science: Physical Science What is the term for the minimum amount of fissile material needed to maintain a nuclear chain reaction? A. Critical mass B. Activation energy C. Half-life D. Binding energy None 94. GED Science: Physical Science What phenomenon is observed when the frequency of a wave source is moving towards an observer increases? A. The Doppler Effect B. The photoelectric effect C. Snell's Law D. Hubble's Law None 95. GED Science: Physical Science In quantum mechanics, what does the wave function of a particle describe? A. The probability of finding a particle in a particular location B. The exact location and velocity of a particle C. The total energy of a particle in a stable orbit D. The electromagnetic field generated by the particle None 96. GED Science: Physical Science Which of the following is a unit of power? A. Joule B. Pascal C. Watt D. Newton None 97. GED Science: Physical Science In a solution, if the solute concentration is higher outside the cell membrane than inside, what is the direction of water movement through osmosis? A. From inside to outside the cell B. From outside to inside the cell C. No movement of water D. Equally in both directions None 98. GED Science: Physical Science What is the primary mechanism by which heat is transferred in fluids? A. Conduction B. Convection C. Radiation D. Diffusion None 99. GED Science: Physical Science Which of the following elements is a liquid at room temperature? A. Mercury B. Gold C. Iron D. Aluminum None 100. GED Science: Life Science In the context of genetic variation, which mechanism is responsible for the new combinations of genetic material seen in sexually reproducing organisms? A. Mutation B. Genetic drift C. Meiosis and fertilization D. Natural selection None 1 out of 100 Time is Up! Time's up
