ASVAB General Science Practice Test 1 2 — Questions and Answers
Question 1: What is the process by which plants convert sunlight, water, and carbon dioxide into glucose and oxygen?
- Cellular respiration
- Fermentation
- Photosynthesis (Correct answer)
- Transpiration
Correct answer: Photosynthesis
Photosynthesis occurs in the chloroplasts of plant cells using chlorophyll to absorb light energy. The overall reaction is: 6CO2 + 6H2O + light energy → C6H12O6 + 6O2. Cellular respiration is essentially the reverse process, breaking down glucose to release energy.
Question 2: A rock layer contains fossils of marine animals, yet the rock is found on a mountaintop. What does this most likely indicate?
- The fossils were carried there by a large animal
- The mountaintop was once covered by a sea, and geological forces lifted it over time (Correct answer)
- Marine animals once lived at high altitudes in the past
- The rock layer formed from volcanic activity that mimics marine features
Correct answer: The mountaintop was once covered by a sea, and geological forces lifted it over time
Marine fossils found at high elevations are classic evidence of plate tectonics and geological uplift. Sedimentary rock forms in ocean floors, trapping marine organisms as fossils. Over millions of years, colliding tectonic plates can push former seabeds upward to form mountains, as occurred with the Himalayas and Appalachians.
Question 3: Which of the following describes a physical change rather than a chemical change?
- Iron rusting when exposed to water and oxygen
- Wood burning to produce ash and smoke
- Ice melting into liquid water (Correct answer)
- Baking soda and vinegar reacting to produce carbon dioxide gas
Correct answer: Ice melting into liquid water
A physical change alters the form or appearance of a substance without changing its chemical composition. Ice melting changes water from solid to liquid — it is still H2O. Chemical changes (like rusting, burning, or the baking soda reaction) produce new substances with different chemical properties.
Question 4: What is the primary function of red blood cells (erythrocytes)?
- To fight infections and produce antibodies
- To transport oxygen from the lungs to body tissues using hemoglobin (Correct answer)
- To initiate blood clotting at sites of injury
- To remove waste products from tissues
Correct answer: To transport oxygen from the lungs to body tissues using hemoglobin
Red blood cells contain hemoglobin, an iron-containing protein that binds to oxygen in the lungs and releases it to cells throughout the body. RBCs lack a nucleus in their mature form, maximizing space for hemoglobin. White blood cells fight infection; platelets handle clotting.
Question 5: According to Newton's Third Law of Motion, when a swimmer pushes backward against the water, what happens?
- The water absorbs the force and nothing pushes back
- The water pushes forward on the swimmer with an equal and opposite force (Correct answer)
- The swimmer's force decreases the water's momentum
- The swimmer experiences a smaller reaction force due to water's density
Correct answer: The water pushes forward on the swimmer with an equal and opposite force
Newton's Third Law states that for every action there is an equal and opposite reaction. When the swimmer pushes the water backward (action), the water pushes the swimmer forward (reaction) with the same magnitude of force. This reaction force propels the swimmer through the water.
Question 6: What layer of Earth's atmosphere contains the ozone layer that protects Earth from harmful ultraviolet radiation?
- Troposphere
- Mesosphere
- Stratosphere (Correct answer)
- Thermosphere
Correct answer: Stratosphere
The ozone layer is located in the stratosphere, approximately 15 to 35 kilometers above Earth's surface. Ozone (O3) molecules absorb most of the Sun's harmful UV-B and UV-C radiation. The troposphere is the lowest layer where weather occurs; the mesosphere is above the stratosphere.
ASVAB General Science Practice Test 1 2
What is the process by which plants convert sunlight, water, and carbon dioxide into glucose and oxygen?