Grade 5 Science Practice Test

Photosynthesis and Cellular Respiration

Plants make their own food through photosynthesis. Using sunlight, carbon dioxide from the air, and water from the soil, plants produce glucose (a sugar) and release oxygen as a byproduct. This process occurs in the chloroplasts of plant cells, which contain a green pigment called chlorophyll that captures light energy. The glucose produced is used by the plant for energy or stored as starch. All living organisms — including plants — also undergo cellular respiration, a process that breaks down glucose and releases the energy stored in it for use by the cell. During respiration, glucose and oxygen react to produce carbon dioxide, water, and usable energy. Plants and animals both respire, but only plants (and some bacteria and algae) also photosynthesize.

1. What are the raw materials (inputs) needed for photosynthesis?

A) Glucose and oxygen B) Carbon dioxide and water C) Sunlight and glucose D) Oxygen and starch

2. What is the role of chlorophyll in photosynthesis?

A) It stores glucose produced during the process. B) It releases oxygen as a waste product. C) It captures light energy used to power photosynthesis. D) It absorbs water from the soil and brings it to the leaves.

3. What do plants do with the glucose produced during photosynthesis?

A) They release it into the soil to feed other organisms. B) They use it for energy or store it as starch. C) They convert it directly into oxygen and release it into the air. D) They pass it to animals through the roots.

4. Which organisms undergo cellular respiration?

A) Only animals B) Only plants C) Only bacteria D) All living organisms, including plants and animals

Question 5. 1-credit Explain how photosynthesis and cellular respiration are opposite processes.

The Rock Cycle

Rocks are constantly being formed, broken down, and reformed in a process called the rock cycle. There are three types of rock. Igneous rock forms when molten rock (magma underground or lava above ground) cools and solidifies. Sedimentary rock forms when layers of sediment — small pieces of rock, shells, or organic material — are compressed and cemented together over time. Metamorphic rock forms when existing rock is subjected to intense heat and pressure, changing its structure without melting it. The rock cycle connects all three types: igneous rock can be weathered into sediment, compressed into sedimentary rock, metamorphosed by heat and pressure, or melted again into magma. No rock type is permanently fixed — all rock eventually changes form, though the process takes millions of years.

6. How does igneous rock form?

A) Layers of sediment are compressed over time. B) Existing rock is changed by heat and pressure without melting. C) Molten rock cools and solidifies. D) Rock is broken down by weathering and deposited in new layers.

7. What is metamorphic rock?

A) Rock formed from cooled lava or magma B) Rock formed from compressed layers of sediment C) Rock that was changed by intense heat and pressure without melting D) Rock dissolved by water and redeposited in a new location

8. What happens to sediment over long periods of time to form sedimentary rock?

A) It melts underground and cools into solid rock. B) It is compressed and cemented together into layers. C) It is heated and squeezed by tectonic plates. D) It is dissolved by water and crystallizes again.

9. Why is the process called the "rock cycle"?

A) Rocks rotate in circles underground. B) The same types of rock always appear in the same order. C) All rocks eventually change from one type to another in an ongoing process. D) Rocks are recycled by humans in a circular manufacturing process.

Question 10. 1-credit Explain one way that igneous rock can eventually become sedimentary rock.

Inherited Traits and Variation

Organisms inherit traits from their parents through genes — segments of DNA found in the chromosomes of cells. Each organism typically inherits one copy of each gene from each parent. Some traits are controlled by a single gene; others are influenced by multiple genes working together. The combination of genes an organism inherits is called its genotype. The physical expression of those genes — what the organism looks like or how it functions — is its phenotype. Not all variation between organisms is inherited. Environmental factors can also influence traits. For example, plants of the same genetic makeup may grow to different sizes depending on the amount of sunlight and water they receive. The combination of inherited traits and environmental influences shapes each individual organism.

11. What carries the genetic information that controls inherited traits?

A) Proteins found in blood B) Genes, which are segments of DNA in chromosomes C) Enzymes produced by the digestive system D) Hormones released by the brain

12. What is the difference between genotype and phenotype?

A) Genotype is what an organism looks like; phenotype is its genetic code. B) Genotype is the combination of genes an organism has; phenotype is how those genes are expressed physically. C) Genotype determines environmental adaptations; phenotype determines inherited traits. D) There is no difference — the two terms are interchangeable.

13. Two plants of identical genetics grow at different sizes. What is the most likely reason?

A) One plant mutated its genes after sprouting. B) Environmental differences such as light or water availability affected their growth. C) One plant inherited more genes from its parent. D) Different soil types changed the plants' genotypes over time.

14. From how many parents does a sexually reproducing organism typically inherit one copy of each gene?

A) One parent B) Two parents C) Three or more parents D) The number of parents varies by species.

Question 15. 1-credit Explain why two siblings from the same parents may look different from each other.

Decomposers and the Nutrient Cycle

Decomposers — primarily fungi and bacteria — play a critical role in ecosystems by breaking down dead organisms and waste products into simpler chemical compounds. This process, called decomposition, releases nutrients such as nitrogen, phosphorus, and carbon back into the soil and water, where they can be absorbed by plants. Without decomposers, dead material would accumulate and the nutrients locked inside would never be recycled. Decomposers are essential to the nitrogen cycle, which moves nitrogen from the atmosphere into the soil and back. Some bacteria convert nitrogen gas from the air into forms that plants can absorb — a process called nitrogen fixation. Plants then take up this nitrogen to build proteins. Animals get nitrogen by eating plants or other animals. When organisms die, decomposers break them down and release nitrogen back into the soil and atmosphere.

16. What do decomposers do in an ecosystem?

A) They capture sunlight and convert it to food. B) They hunt and eat primary consumers. C) They break down dead organisms and return nutrients to the soil. D) They transport nutrients from the soil into plant roots.

17. What would happen to an ecosystem if all decomposers disappeared?

A) Plants would grow faster because there would be no competition for nutrients. B) Dead material would accumulate and nutrients would not be recycled back to the soil. C) Animals would take on the role of decomposers by eating dead organisms. D) The ecosystem would eventually reach a stable balance without decomposers.

18. What is nitrogen fixation?

A) The process by which plants store nitrogen as starch B) The conversion of nitrogen gas from the air into forms plants can absorb C) The release of nitrogen from animal waste into the atmosphere D) The chemical reaction that joins nitrogen to oxygen in soil water

19. How do animals obtain the nitrogen they need?

A) They absorb it directly from the air through their lungs. B) They drink water that contains dissolved nitrogen. C) They eat plants or other animals that contain nitrogen in their proteins. D) They extract it from soil through their skin.

Question 20. 1-credit Explain why decomposers are important to producers (plants) in an ecosystem.

Simple Machines and Work

A simple machine is a device that changes the direction or magnitude of a force, making work easier. The six types of simple machines are the lever, wheel and axle, pulley, inclined plane, wedge, and screw. A lever consists of a rigid bar that pivots on a fulcrum. By placing the fulcrum closer to a heavy load, a small force applied at the opposite end can lift the load. A pulley uses a wheel and rope to redirect force, and multiple pulleys can multiply the force applied. An inclined plane (a ramp) spreads the work of lifting over a longer distance, requiring less force at any one time. While simple machines reduce the force needed, they do not reduce the total work done — the trade-off is that a smaller force must be applied over a longer distance.

21. What is the main purpose of a simple machine?

A) To increase the total amount of work done B) To change the direction or magnitude of a force to make work easier C) To eliminate the need for any force to move an object D) To store energy for later use

22. How does moving a fulcrum closer to a load affect a lever?

A) It requires more force at the opposite end to lift the load. B) It requires less force at the opposite end to lift the load. C) It has no effect on the force needed. D) It doubles the weight of the load.

23. How does an inclined plane make it easier to lift a heavy object?

A) It reduces the total work that needs to be done. B) It increases the force applied at any one moment. C) It spreads work over a longer distance so less force is needed at any point. D) It converts gravitational energy into mechanical energy.

24. Why do simple machines not reduce the total work done?

A) They always add friction that increases total work. B) A reduced force must be applied over a longer distance, keeping total work the same. C) Simple machines convert work into heat, which cancels any savings. D) The weight of the machine itself adds to the total work required.

Question 25. 1-credit Give one example of how a simple machine is used in everyday life and explain how it makes a task easier.

Natural Disasters and Earth's Surface

Natural disasters can quickly reshape Earth's surface. Earthquakes occur when stress that has built up along tectonic plate boundaries is suddenly released, sending seismic waves through the ground. Strong earthquakes can crack the ground, collapse buildings, and, if they occur under the ocean, trigger tsunamis — massive waves that travel across the ocean and inundate coastal areas. Volcanoes erupt when magma from the mantle reaches the surface, releasing lava, ash, and gases. Volcanic ash can travel hundreds of miles and block sunlight, affecting climate. Over time, lava cools to form new land. Landslides occur when unstable rock or soil on a slope loses support — often after heavy rain or earthquakes — and rapidly slides downhill. Floods occur when water overflows its normal boundaries, caused by intense rainfall, rapid snowmelt, or storm surges from hurricanes.

26. What causes an earthquake?

A) Magma pushing up through the crust from the mantle B) The sudden release of stress built up along tectonic plate boundaries C) Heavy rainfall saturating the ground and causing it to shift D) Large waves striking coastlines and shaking the ground

27. How can volcanic eruptions affect climate?

A) Lava flows into the ocean and raises sea levels significantly. B) Volcanic gases cause acid rain that melts glaciers. C) Ash clouds block sunlight, temporarily lowering temperatures. D) Heat from lava warms the surrounding atmosphere permanently.

28. What combination of conditions often triggers a landslide?

A) Cold temperatures and strong winds B) Unstable soil or rock on a slope that loses support, often after rain or earthquakes C) Ocean waves undercutting a cliff over thousands of years D) A sudden increase in air pressure above a mountainous region

29. How do underwater earthquakes cause tsunamis?

A) They heat the ocean water, causing massive evaporation. B) They displace large amounts of water, generating massive waves that travel across the ocean. C) They shift ocean currents, pushing water toward coastlines. D) They pull the ocean floor down, creating a vacuum that water rushes to fill.

Question 30. 1-credit Explain one positive and one negative effect of volcanic eruptions on Earth's surface.

Ocean Currents and Climate

Ocean currents are large, continuous movements of ocean water driven by differences in temperature and salinity (salt content), as well as by wind. Warm water from the tropics flows toward the poles, and cold water near the poles flows back toward the equator, creating a global system called thermohaline circulation — sometimes called the ocean conveyor belt. Ocean currents significantly influence climate. The Gulf Stream, a warm current in the North Atlantic, carries heat from the Gulf of Mexico to Western Europe, making the climate there much milder than other regions at the same latitude. Currents also affect precipitation patterns and can intensify or weaken storms. Ocean temperatures influence hurricane strength — warmer surface water provides more energy for hurricane formation. Rising global temperatures are altering ocean currents, potentially disrupting the climate systems that millions of people depend on.

31. What drives ocean currents?

A) Differences in temperature and salinity, and wind B) Rotation of Earth around the sun C) Tidal forces from the moon pulling water in different directions D) Differences in atmospheric pressure above the ocean surface

32. How does the Gulf Stream affect Western Europe's climate?

A) It brings cold water that keeps summers mild and winters short. B) It carries warm water that makes the climate milder than other regions at the same latitude. C) It causes heavy rainfall in winter and drought in summer. D) It has no significant effect on Western Europe's climate.

33. How do warmer ocean surface temperatures affect hurricanes?

A) They weaken hurricanes by reducing air pressure over the ocean. B) They slow hurricanes down by increasing water resistance. C) They provide more energy for hurricane formation and intensification. D) They redirect hurricanes away from land masses.

34. What is thermohaline circulation?

A) A type of storm caused by differences in ocean temperature B) The global system of ocean currents driven by temperature and salinity differences C) The process by which ocean water evaporates to form clouds D) A current that only affects tropical regions near the equator

Question 35. 1-credit Explain how ocean currents affect climate in coastal regions.

Stars and Life Cycles

Stars are enormous balls of hot gas held together by gravity and powered by nuclear fusion — a process in which hydrogen atoms are fused together under extreme pressure and temperature, releasing tremendous amounts of energy as light and heat. Our sun is an average-sized star. All stars are born in nebulae — vast clouds of gas and dust — when gravity pulls the material together until it becomes dense enough to begin fusion. Stars spend most of their lives in a stable phase called the main sequence. How long a star spends in this phase depends on its mass — larger stars burn through their fuel faster. When a star runs out of hydrogen fuel, it expands into a red giant. A star like our sun will eventually shed its outer layers, leaving a small, dense core called a white dwarf. More massive stars end in a dramatic explosion called a supernova, leaving behind either a neutron star or a black hole.

36. What powers stars like our sun?

A) The gravitational pull of nearby planets B) Chemical reactions between hydrogen and oxygen C) Nuclear fusion of hydrogen atoms D) Electrical energy generated by magnetic fields

37. Where are stars born?

A) In the cores of existing stars when they explode B) In nebulae — clouds of gas and dust pulled together by gravity C) In black holes that release material when they collapse D) From comets and asteroids that accumulate in orbit around a planet

38. How does a star's mass affect its lifetime?

A) More massive stars live longer because they have more fuel. B) All stars live approximately the same length of time regardless of mass. C) More massive stars burn through fuel faster and live shorter lives. D) Less massive stars burn out instantly because they lack enough pressure for fusion.

39. What does a star like our sun eventually become after the red giant phase?

A) A neutron star B) A black hole C) A supernova D) A white dwarf

Question 40. 1-credit Explain what happens to a star when it runs out of hydrogen fuel.

Grade 5 Science Practice Test — Version C