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Grade 7 · Science · curriculum collection

Grade 7 Science, NGSS domains

8 units for Grade 7 science, organised by NGSS disciplinary core idea domain: Physical Sciences, Life Sciences, Earth and Space Sciences. Each unit has a short lesson, a practice worksheet and a review worksheet, both with answer keys.

8 units16 worksheets192 questions with answers
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Answer-checked and approved on 29 October 2026

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Aligned by StudyBrix at domain level. Not an official publication of, or endorsed by, the standards' authors. Framework: Next Generation Science Standards.

Units in teaching order

01

PS Physical Sciences

Matter & forces

Properties of materials, states of matter, forces and simple measurements of motion and density.

Short lesson: Matter and changes

Study guide for Grades 3 to 7: 20 key ideas, including solid, liquid and gas; 3 practice questions.

A change of state is physical. Heating does not automatically mean a new substance has formed.

  • Solid. A state of matter with a definite shape and volume under ordinary classroom conditions.
  • Liquid. A state of matter with a definite volume that takes the shape of its container.
  • Gas. A state of matter that expands to fill the available container.
  • Melting. A change from solid to liquid.

Read the full study guide

Worksheets

A practice worksheet and a review worksheet, 12 and 12 questions.

Worksheets (PDF)Answer keys (PDF)
Practice worksheet: 12 questions

  1. A model vehicle travels 3300 m in 33 s at constant speed. What is its speed in m/s?

  2. A sample has mass 170 g and volume 17 cm³. Calculate density in g/cm³.

  3. What is the change from liquid water to water vapour called?

    1. Evaporation
    2. Condensation
    3. Freezing
    4. Melting

  4. Matter and changes: which term fits this description? A change from liquid to solid.

    1. Mass
    2. Freezing
    3. Physical change
    4. Melting

  5. During melting, which statement best describes a simple particle model?

    1. Particles become less fixed in their arrangement.
    2. All particles split into atoms.
    3. Particles stop moving.
    4. Mass must double.

  6. Which material is generally a good conductor of electricity?

    1. Rubber
    2. Copper
    3. Glass
    4. Dry wood

  7. Which force pulls a dropped ball towards Earth?

    1. Friction only
    2. Gravity
    3. Sound
    4. Magnetism

  8. A model vehicle travels 1430 m in 26 s at constant speed. What is its speed in m/s?

  9. A sample has mass 184 g and volume 46 cm³. Calculate density in g/cm³.

  10. Matter and changes: which term fits this description? A combination of substances not all chemically bonded into a single pure substance.

    1. Mixture
    2. Physical change
    3. Density
    4. Freezing

  11. State one limitation of a simple drawing of circles used to model a liquid.

  12. A model vehicle travels 405 m in 5 s at constant speed. What is its speed in m/s?

Answer key
  1. 100 m/s 3300 ÷ 33 = 100 m/s
  2. 10 g/cm³ 170 ÷ 17 = 10 g/cm³
  3. Evaporation
  4. Freezing Freezing: A change from liquid to solid.
  5. Particles become less fixed in their arrangement.
  6. Copper
  7. Gravity
  8. 55 m/s 1430 ÷ 26 = 55 m/s
  9. 4 g/cm³ 184 ÷ 46 = 4 g/cm³
  10. Mixture Mixture: A combination of substances not all chemically bonded into a single pure substance.
  11. It may omit three-dimensional motion, molecular shapes, scale, interactions or the variety of particle types.
  12. 81 m/s 405 ÷ 5 = 81 m/s
Review worksheet: 12 questions

  1. A model vehicle travels 4557 m in 49 s at constant speed. What is its speed in m/s?

  2. A sample has mass 84 g and volume 28 cm³. Calculate density in g/cm³.

  3. In a solid, particles are best described as

    1. usually kilometres apart
    2. vibrating around relatively fixed positions
    3. having no interactions
    4. completely motionless

  4. Matter and changes: which term fits this description? A measure of an object's inertia, expressed in kilograms in SI.

    1. Mass
    2. Density
    3. Conductor
    4. Gas

  5. A model vehicle travels 242 m in 22 s at constant speed. What is its speed in m/s?

  6. A sample has mass 748 g and volume 68 cm³. Calculate density in g/cm³.

  7. A sealed container holds liquid water and water vapour. When vapour condenses, what happens to total water mass?

    1. It becomes zero.
    2. It must decrease.
    3. It stays the same if nothing enters or leaves.
    4. It doubles automatically.

  8. Matter and changes: which term fits this description? A state of matter with a definite shape and volume under ordinary classroom conditions.

    1. Liquid
    2. Solid
    3. Sublimation
    4. Freezing

  9. A model vehicle travels 567 m in 27 s at constant speed. What is its speed in m/s?

  10. A sample has mass 374 g and volume 34 cm³. Calculate density in g/cm³.

  11. Which is evidence of diffusion?

    1. A dissolved dye gradually spreads through still water.
    2. A solid gains a name.
    3. A ruler becomes longer on paper.
    4. A scale is switched off.

  12. Matter and changes: which term fits this description? A material through which electricity or heat can pass relatively readily.

    1. Conductor
    2. Solid
    3. Density
    4. Deposition
Answer key
  1. 93 m/s 4557 ÷ 49 = 93 m/s
  2. 3 g/cm³ 84 ÷ 28 = 3 g/cm³
  3. vibrating around relatively fixed positions
  4. Mass Mass: A measure of an object's inertia, expressed in kilograms in SI.
  5. 11 m/s 242 ÷ 22 = 11 m/s
  6. 11 g/cm³ 748 ÷ 68 = 11 g/cm³
  7. It stays the same if nothing enters or leaves.
  8. Solid Solid: A state of matter with a definite shape and volume under ordinary classroom conditions.
  9. 21 m/s 567 ÷ 27 = 21 m/s
  10. 11 g/cm³ 374 ÷ 34 = 11 g/cm³
  11. A dissolved dye gradually spreads through still water.
  12. Conductor Conductor: A material through which electricity or heat can pass relatively readily.

Related ready-made worksheets: Grade 7 Matter & forces worksheet

02

PS Physical Sciences

Motion and energy

Calculations with velocity, acceleration, force, work, energy and power.

Short lesson: Motion, forces and energy

Study guide for Grades 7 to 11: 20 key ideas, including distance, displacement and speed; 3 practice questions.

Zero net force means zero acceleration, not necessarily zero velocity. An object can move steadily in equilibrium.

  • Distance. The total length of the path travelled by an object.
  • Displacement. The directed change from initial position to final position.
  • Speed. The rate at which distance is travelled.
  • Velocity. The rate of change of position, including direction.

Read the full study guide

Worksheets

A practice worksheet and a review worksheet, 12 and 12 questions.

Worksheets (PDF)Answer keys (PDF)
Practice worksheet: 12 questions

  1. An object moves at constant velocity -19 m/s for 39 s. Find displacement in m.

  2. A device receives 7900 J and delivers 7110 J of useful energy. Find its efficiency as a percentage.

  3. Motion, forces and energy: which term fits this description? A contact force perpendicular to the contact surface.

    1. Gravitational potential energy
    2. Scalar
    3. Normal force
    4. Inertia

  4. A device receives 250 J and delivers 75 J as useful output. Find its efficiency as a percentage.

  5. An object moves at constant velocity 0 m/s for 24 s. Find displacement in m.

  6. A device receives 1900 J and delivers 950 J of useful energy. Find its efficiency as a percentage.

  7. Motion, forces and energy: which term fits this description? A physical quantity described by magnitude and direction.

    1. Vector
    2. Acceleration
    3. Tension
    4. Impulse

  8. A machine transfers 480 J in 8 s. Calculate average power in W.

  9. An object moves at constant velocity 27 m/s for 10 s. Find displacement in m.

  10. A device receives 4700 J and delivers 940 J of useful energy. Find its efficiency as a percentage.

  11. Motion, forces and energy: which term fits this description? The product of an object's mass and its velocity in classical mechanics.

    1. Distance
    2. Momentum
    3. Friction
    4. Tension

  12. A force of 12 N acts along a displacement of 3 m. Calculate the work in J.

Answer key
  1. -741 m -19 × 39 = -741
  2. 90 % 7110/7900 × 100 = 90%
  3. Normal force Normal force: A contact force perpendicular to the contact surface.
  4. 30 75/250 × 100 = 30%.
  5. 0 m 0 × 24 = 0
  6. 50 % 950/1900 × 100 = 50%
  7. Vector Vector: A physical quantity described by magnitude and direction.
  8. 60 Power = energy/time = 480/8.
  9. 270 m 27 × 10 = 270
  10. 20 % 940/4700 × 100 = 20%
  11. Momentum Momentum: The product of an object's mass and its velocity in classical mechanics.
  12. 36 For constant aligned force, work = force × displacement.
Review worksheet: 12 questions

  1. An object moves at constant velocity -23 m/s for 16 s. Find displacement in m.

  2. A device receives 5400 J and delivers 4050 J of useful energy. Find its efficiency as a percentage.

  3. An efficiency greater than 100% in a basic device calculation most likely signals

    1. a negative input time necessarily
    2. that conservation is irrelevant
    3. energy created freely
    4. an error or inconsistent system accounting

  4. Motion, forces and energy: which term fits this description? The tendency of an object to resist changes in its velocity.

    1. Distance
    2. Inertia
    3. Elastic collision
    4. Momentum

  5. An object moves at constant velocity 8 m/s for 28 s. Find displacement in m.

  6. A device receives 6100 J and delivers 915 J of useful energy. Find its efficiency as a percentage.

  7. In a simple model of a falling object, gravitational potential energy can become

    1. kinetic energy
    2. only chemical energy
    3. new mass created from nothing in this model
    4. zero energy everywhere

  8. Motion, forces and energy: which term fits this description? The time integral of force, equal to the resulting change in momentum.

    1. Tension
    2. Acceleration
    3. Impulse
    4. Momentum

  9. An object moves at constant velocity -13 m/s for 13 s. Find displacement in m.

  10. A device receives 4800 J and delivers 4080 J of useful energy. Find its efficiency as a percentage.

  11. Which unit measures power?

    1. kilogram
    2. watt
    3. newton metre per metre
    4. joule

  12. Motion, forces and energy: which term fits this description? The rate of change of position, including direction.

    1. Velocity
    2. Vector
    3. Tension
    4. Kinetic energy
Answer key
  1. -368 m -23 × 16 = -368
  2. 75 % 4050/5400 × 100 = 75%
  3. an error or inconsistent system accounting Check units, measurements and which inputs and outputs were included.
  4. Inertia Inertia: The tendency of an object to resist changes in its velocity.
  5. 224 m 8 × 28 = 224
  6. 15 % 915/6100 × 100 = 15%
  7. kinetic energy Motion increases as gravitational potential energy decreases.
  8. Impulse Impulse: The time integral of force, equal to the resulting change in momentum.
  9. -169 m -13 × 13 = -169
  10. 85 % 4080/4800 × 100 = 85%
  11. watt Power is energy transferred per unit time.
  12. Velocity Velocity: The rate of change of position, including direction.

Related ready-made worksheets: Grade 7 Motion & energy worksheet

03

PS Physical Sciences

Motion & graphs

Distance, displacement, speed, velocity and acceleration.

Short lesson: Distance is not displacement

Study guide for Grades 6 to 9: 4 key ideas, including path length, change in position and round trips; 2 worked examples and 3 practice questions. Use paths and signed positions to explain round trips.

  • Path length. Distance is the total length travelled and is non-negative.
  • Change in position. Displacement is final position minus initial position and includes a direction or sign.
  • Round trips. Returning to the start makes displacement zero, but travelled distance need not be zero.
  • State the reference. Define your origin and positive direction before calculating signed displacement.

Worked example

A learner walks 9 m east, then 4 m west on one line. Find total distance.

Distance adds both path lengths: 9 + 4 = 13 m.

Answer: 13 m

Read the full study guide

Worksheets

A practice worksheet and a review worksheet, 12 and 12 questions.

Worksheets (PDF)Answer keys (PDF)
Practice worksheet: 12 questions

  1. A rover travels 354 m in 64 s, then 282 m in 29 s. Find its average speed for both stages. Round to 3 decimal places if needed. Answer in m/s.

  2. A robot moves 122 m east and then 70 m west along a straight line. Find the total distance travelled. Round to 3 decimal places if needed. Answer in m.

  3. On an east-positive axis, position changes from -17 m to 39 m in 4 s. Find the signed average velocity. Round to 3 decimal places if needed. Answer in m/s.

  4. Why can a round trip have zero average velocity but nonzero average speed?

  5. Which straight segment shows larger speed: slope +2 m/s or slope −5 m/s?

    1. The +2 m/s segment
    2. The −5 m/s segment
    3. Both have the same speed

  6. A learner walks 9 m east, then 4 m west on one line. Find total distance.

  7. A rover travels 313 m in 29 s, then 218 m in 26 s. Find its average speed for both stages. Round to 3 decimal places if needed. Answer in m/s.

  8. A robot moves 10 m east and then 6 m west along a straight line. Find the total distance travelled. Round to 3 decimal places if needed. Answer in m.

  9. On an east-positive axis, position changes from 47 m to 52 m in 22 s. Find the signed average velocity. Round to 3 decimal places if needed. Answer in m/s.

  10. Which interval belongs in average speed for an entire outing?

    1. Moving time only in every case
    2. The shortest moving stage
    3. All elapsed time, including stops

  11. An object stays at position −7 m from 2 s to 8 s. Find its average velocity over that interval.

  12. Why is a negative displacement not a negative distance travelled?

Answer key
  1. 6.839 m/s v̄ = (d₁ + d₂)/(t₁ + t₂) (354 + 282) / (64 + 29) = 6.839
  2. 192 m distance = forward path + return path 122 + 70 = 192
  3. 14 m/s v̄ = (x₂ − x₁)/Δt (39 − (-17)) / 4 = 14
  4. Displacement is zero while total distance is positive. Look for the different numerators rather than claiming the object never moved.
  5. The −5 m/s segment Speed is the magnitude of velocity; 5 is greater than 2.
  6. 13 m Distance adds both path lengths: 9 + 4 = 13 m.
  7. 9.655 m/s v̄ = (d₁ + d₂)/(t₁ + t₂) (313 + 218) / (29 + 26) = 9.655
  8. 16 m distance = forward path + return path 10 + 6 = 16
  9. 0.227 m/s v̄ = (x₂ − x₁)/Δt (52 − (47)) / 22 = 0.227
  10. All elapsed time, including stops Average speed for the whole interval includes the whole elapsed time.
  11. 0 m/s Its position change is zero despite its negative position.
  12. The minus sign identifies direction, not a negative path length. Credit the scalar/vector distinction without requiring these exact terms.
Review worksheet: 12 questions

  1. On an east-positive axis, position changes from -12 m to -12 m in 15 s. Find the signed average velocity. Round to 3 decimal places if needed. Answer in m/s.

  2. A robot moves 54 m east and then 14 m west along a straight line. Find the total distance travelled. Round to 3 decimal places if needed. Answer in m.

  3. A rover travels 100 m in 30 s, then 375 m in 54 s. Find its average speed for both stages. Round to 3 decimal places if needed. Answer in m/s.

  4. A toy travels 30 m in 10 s, pauses for 5 s, then travels 15 m in 5 s. Find overall average speed.

  5. A constant velocity of 4 m/s lasts 3 s. Find displacement.

  6. A runner returns to the start after one complete lap. Which is zero?

    1. Elapsed time necessarily
    2. Displacement
    3. Distance travelled

  7. On an east-positive axis, position changes from 19 m to 34 m in 14 s. Find the signed average velocity. Round to 3 decimal places if needed. Answer in m/s.

  8. A robot moves 95 m east and then 35 m west along a straight line. Find the total distance travelled. Round to 3 decimal places if needed. Answer in m.

  9. A rover travels 191 m in 72 s, then 25 m in 45 s. Find its average speed for both stages. Round to 3 decimal places if needed. Answer in m/s.

  10. Two travel stages take different amounts of time. Why is a simple mean of their speeds unreliable?

  11. Position is 2 m at 1 s and 14 m at 5 s. Find average velocity.

  12. For the same 9 m east and 4 m west trip, use east-positive. Find displacement.

Answer key
  1. 0 m/s v̄ = (x₂ − x₁)/Δt (-12 − (-12)) / 15 = 0
  2. 68 m distance = forward path + return path 54 + 14 = 68
  3. 5.655 m/s v̄ = (d₁ + d₂)/(t₁ + t₂) (100 + 375) / (30 + 54) = 5.655
  4. 2.25 m/s Total distance 45 m divided by total time 20 s gives 2.25 m/s.
  5. 12 m Displacement equals velocity × time: 4 × 3 = 12 m.
  6. Displacement Final and initial positions coincide, so displacement is zero.
  7. 1.071 m/s v̄ = (x₂ − x₁)/Δt (34 − (19)) / 14 = 1.071
  8. 130 m distance = forward path + return path 95 + 35 = 130
  9. 1.846 m/s v̄ = (d₁ + d₂)/(t₁ + t₂) (191 + 25) / (72 + 45) = 1.846
  10. Longer stages have more time weight; use total distance divided by total time. Credit correct time weighting or a valid numerical counterexample.
  11. 3 m/s The slope is (14 − 2)/(5 − 1) = 3 m/s.
  12. 5 m Signed displacement is +9 − 4 = +5 m.

Related ready-made worksheets: Grade 7 Motion & graphs worksheet

04

PS Physical Sciences

Energy, work & power

Energy stores and transfers, work, power and efficiency.

Short lesson: Gravitational energy gain

Study guide for Grades 7 to 10: 2 worked examples and 2 practice questions. Use the vertical height change and the specified constant field strength.

ΔEₚ = mgΔh

Use the vertical height change and the specified constant field strength.

Worked example

A 12 kg load is raised vertically by 7 m in a field g = 10 N/kg. Find its gravitational potential-energy gain. Round to 3 decimal places if needed. Answer in J.

ΔEₚ = mgΔh 12 × 10 × 7 = 840

Answer: 840 J

Read the full study guide

Worksheets

A practice worksheet and a review worksheet, 12 and 12 questions.

Worksheets (PDF)Answer keys (PDF)
Practice worksheet: 12 questions

  1. A 21 kg load is raised vertically by 22 m in a field g = 10 N/kg. Find its gravitational potential-energy gain. Round to 3 decimal places if needed. Answer in J.

  2. A model device transfers energy at constant power 695 W for 38 s. Find the transferred energy. Round to 3 decimal places if needed. Answer in J.

  3. A 2 kg load is raised vertically by 26 m in a field g = 10 N/kg. Find its gravitational potential-energy gain. Round to 3 decimal places if needed. Answer in J.

  4. A model device transfers energy at constant power 745 W for 6 s. Find the transferred energy. Round to 3 decimal places if needed. Answer in J.

  5. A 6 kg load is raised vertically by 28 m in a field g = 10 N/kg. Find its gravitational potential-energy gain. Round to 3 decimal places if needed. Answer in J.

  6. A model device transfers energy at constant power 75 W for 55 s. Find the transferred energy. Round to 3 decimal places if needed. Answer in J.

  7. A 38 kg load is raised vertically by 11 m in a field g = 10 N/kg. Find its gravitational potential-energy gain. Round to 3 decimal places if needed. Answer in J.

  8. A model device transfers energy at constant power 580 W for 82 s. Find the transferred energy. Round to 3 decimal places if needed. Answer in J.

  9. A 14 kg load is raised vertically by 26 m in a field g = 10 N/kg. Find its gravitational potential-energy gain. Round to 3 decimal places if needed. Answer in J.

  10. A model device transfers energy at constant power 985 W for 18 s. Find the transferred energy. Round to 3 decimal places if needed. Answer in J.

  11. A 34 kg load is raised vertically by 30 m in a field g = 10 N/kg. Find its gravitational potential-energy gain. Round to 3 decimal places if needed. Answer in J.

  12. A model device transfers energy at constant power 790 W for 52 s. Find the transferred energy. Round to 3 decimal places if needed. Answer in J.

Answer key
  1. 4620 J ΔEₚ = mgΔh 21 × 10 × 22 = 4620
  2. 26410 J E = Pt 695 × 38 = 26410
  3. 520 J ΔEₚ = mgΔh 2 × 10 × 26 = 520
  4. 4470 J E = Pt 745 × 6 = 4470
  5. 1680 J ΔEₚ = mgΔh 6 × 10 × 28 = 1680
  6. 4125 J E = Pt 75 × 55 = 4125
  7. 4180 J ΔEₚ = mgΔh 38 × 10 × 11 = 4180
  8. 47560 J E = Pt 580 × 82 = 47560
  9. 3640 J ΔEₚ = mgΔh 14 × 10 × 26 = 3640
  10. 17730 J E = Pt 985 × 18 = 17730
  11. 10200 J ΔEₚ = mgΔh 34 × 10 × 30 = 10200
  12. 41080 J E = Pt 790 × 52 = 41080
Review worksheet: 12 questions

  1. A 24 kg load is raised vertically by 13 m in a field g = 10 N/kg. Find its gravitational potential-energy gain. Round to 3 decimal places if needed. Answer in J.

  2. A model device transfers energy at constant power 270 W for 48 s. Find the transferred energy. Round to 3 decimal places if needed. Answer in J.

  3. A 40 kg load is raised vertically by 2 m in a field g = 10 N/kg. Find its gravitational potential-energy gain. Round to 3 decimal places if needed. Answer in J.

  4. A model device transfers energy at constant power 775 W for 52 s. Find the transferred energy. Round to 3 decimal places if needed. Answer in J.

  5. A 15 kg load is raised vertically by 24 m in a field g = 10 N/kg. Find its gravitational potential-energy gain. Round to 3 decimal places if needed. Answer in J.

  6. A model device transfers energy at constant power 160 W for 56 s. Find the transferred energy. Round to 3 decimal places if needed. Answer in J.

  7. A 2 kg load is raised vertically by 20 m in a field g = 10 N/kg. Find its gravitational potential-energy gain. Round to 3 decimal places if needed. Answer in J.

  8. A model device transfers energy at constant power 300 W for 46 s. Find the transferred energy. Round to 3 decimal places if needed. Answer in J.

  9. A 16 kg load is raised vertically by 23 m in a field g = 10 N/kg. Find its gravitational potential-energy gain. Round to 3 decimal places if needed. Answer in J.

  10. A model device transfers energy at constant power 530 W for 26 s. Find the transferred energy. Round to 3 decimal places if needed. Answer in J.

  11. A 34 kg load is raised vertically by 26 m in a field g = 10 N/kg. Find its gravitational potential-energy gain. Round to 3 decimal places if needed. Answer in J.

  12. A model device transfers energy at constant power 960 W for 67 s. Find the transferred energy. Round to 3 decimal places if needed. Answer in J.

Answer key
  1. 3120 J ΔEₚ = mgΔh 24 × 10 × 13 = 3120
  2. 12960 J E = Pt 270 × 48 = 12960
  3. 800 J ΔEₚ = mgΔh 40 × 10 × 2 = 800
  4. 40300 J E = Pt 775 × 52 = 40300
  5. 3600 J ΔEₚ = mgΔh 15 × 10 × 24 = 3600
  6. 8960 J E = Pt 160 × 56 = 8960
  7. 400 J ΔEₚ = mgΔh 2 × 10 × 20 = 400
  8. 13800 J E = Pt 300 × 46 = 13800
  9. 3680 J ΔEₚ = mgΔh 16 × 10 × 23 = 3680
  10. 13780 J E = Pt 530 × 26 = 13780
  11. 8840 J ΔEₚ = mgΔh 34 × 10 × 26 = 8840
  12. 64320 J E = Pt 960 × 67 = 64320

Related ready-made worksheets: Grade 7 Energy, work & power worksheet

05

LS Life Sciences

Plant biology

Plant parts, what plants need, photosynthesis and plant reproduction.

Short lesson: Photosynthesis and matter sources

Study guide for Grades 7 to 10: 4 key ideas, including process, carbon and chloroplasts; 2 worked examples and 3 practice questions. Trace carbon as well as energy.

  • Process. Photosynthesis uses light energy to build energy-rich organic compounds from simpler starting materials.
  • Carbon. In the familiar plant model, carbon dioxide supplies carbon for sugar production.
  • Chloroplasts. Photosynthetic machinery is located in chloroplasts in many plant cells.
  • Whole plant. Plants also respire; photosynthesis is not their only energy-related process.

Worked example

Where does much of the carbon in newly made plant sugar come from?

CO₂ supplies carbon in the photosynthesis model.

Answer: Carbon dioxide.

Read the full study guide

Worksheets

A practice worksheet and a review worksheet, 12 and 12 questions.

Worksheets (PDF)Answer keys (PDF)
Practice worksheet: 12 questions

  1. In supplied data, 21 of 48 seeds germinated under the stated test conditions. Find the sample germination percentage. Round to 3 decimal places if needed. Answer in %.

  2. What should be included when reporting a photosynthesis investigation?

    1. Only the expected conclusion.
    2. Conditions, method, measurements and uncertainty.
    3. Only a picture with no labels.

  3. What does dispersal describe?

    1. Movement of seeds or other reproductive units away from their source.
    2. Only DNA copying.
    3. Always gamete fusion.

  4. In supplied data, 44 of 182 seeds germinated under the stated test conditions. Find the sample germination percentage. Round to 3 decimal places if needed. Answer in %.

  5. Why does an oxygen-bubble count give only an indirect measure of photosynthesis?

  6. A sample has 40 seeds and 30 germinate under the stated test conditions. Find the germination percentage.

  7. In supplied data, 61 of 100 seeds germinated under the stated test conditions. Find the sample germination percentage. Round to 3 decimal places if needed. Answer in %.

  8. Where does much of the carbon in newly made plant sugar come from?

    1. Only mineral particles from soil.
    2. Sunlight atoms.
    3. Carbon dioxide.

  9. Which event is pollination?

    1. Every seed germinating.
    2. Pollen reaching a receptive stigma.
    3. Roots absorbing water.

  10. In supplied data, 13 of 87 seeds germinated under the stated test conditions. Find the sample germination percentage. Round to 3 decimal places if needed. Answer in %.

  11. Why is saying plants get all their food from soil misleading?

  12. Why is a seed not the same thing as pollen?

Answer key
  1. 43.75 % percentage = germinated/tested × 100 21/48 × 100 = 43.75
  2. Conditions, method, measurements and uncertainty. Interpretation depends on the measurement context.
  3. Movement of seeds or other reproductive units away from their source. Dispersal concerns location changes.
  4. 24.176 % percentage = germinated/tested × 100 44/182 × 100 = 24.176
  5. Bubble size, dissolved gas and other processes can affect the observation. Treat a proxy as limited evidence, not an exact molecule count.
  6. 75 % 30/40 × 100 = 75%.
  7. 61 % percentage = germinated/tested × 100 61/100 × 100 = 61
  8. Carbon dioxide. CO₂ supplies carbon in the photosynthesis model.
  9. Pollen reaching a receptive stigma. Pollination is pollen transfer, not fertilization itself.
  10. 14.943 % percentage = germinated/tested × 100 13/87 × 100 = 14.943
  11. Plants generally make sugars using carbon dioxide and water, while soil supplies water and mineral nutrients. Distinguish organic food molecules from mineral resources.
  12. A seed contains an embryo after reproductive development; pollen has a different role in reproduction. Keep the biological stages distinct.
Review worksheet: 12 questions

  1. In supplied data, 148 of 175 seeds germinated under the stated test conditions. Find the sample germination percentage. Round to 3 decimal places if needed. Answer in %.

  2. Which event is fertilization?

    1. Fusion of gametes.
    2. Only petals opening.
    3. Only wind moving a seed.

  3. Which comparison can test a light-related effect more fairly?

    1. Different species with different water, soil and age at once.
    2. One leaf drawn twice.
    3. Comparable plants differing in light exposure while other conditions are controlled.

  4. In supplied data, 18 of 98 seeds germinated under the stated test conditions. Find the sample germination percentage. Round to 3 decimal places if needed. Answer in %.

  5. Must pollination always be carried out by insects?

    1. No; wind and other agents can be involved.
    2. Only if a flower is yellow.
    3. Yes, all plants use bees.

  6. What is the role of light in photosynthesis?

    1. It is a mineral nutrient.
    2. It supplies all carbon atoms.
    3. It provides energy.

  7. In supplied data, 42 of 124 seeds germinated under the stated test conditions. Find the sample germination percentage. Round to 3 decimal places if needed. Answer in %.

  8. Which conclusion is justified by 30 of 40 tested seeds germinating?

    1. Exactly 75% of all future seeds everywhere will germinate.
    2. 75% germinated in this tested sample and conditions.
    3. The other seeds are certainly all dead.

  9. Do plants also carry out cellular respiration?

    1. Only when every leaf falls off.
    2. No, only animals respire.
    3. Yes.

  10. In supplied data, 48 of 111 seeds germinated under the stated test conditions. Find the sample germination percentage. Round to 3 decimal places if needed. Answer in %.

  11. Why should the conditions of a germination test be reported?

  12. A simplified equation uses 6 CO₂ to represent formation of one glucose molecule. How many carbon atoms are supplied?

Answer key
  1. 84.571 % percentage = germinated/tested × 100 148/175 × 100 = 84.571
  2. Fusion of gametes. Fertilization combines genetic material through gamete fusion.
  3. Comparable plants differing in light exposure while other conditions are controlled. Control other influential variables.
  4. 18.367 % percentage = germinated/tested × 100 18/98 × 100 = 18.367
  5. No; wind and other agents can be involved. Pollination mechanisms vary.
  6. It provides energy. Light energy powers the process rather than supplying carbon matter.
  7. 33.871 % percentage = germinated/tested × 100 42/124 × 100 = 33.871
  8. 75% germinated in this tested sample and conditions. Limit the conclusion to the evidence.
  9. Yes. Plant cells use respiration as well as photosynthesis.
  10. 43.243 % percentage = germinated/tested × 100 48/111 × 100 = 43.243
  11. Water, temperature, oxygen, dormancy and other factors can affect the result. A test percentage is condition-dependent.
  12. 6 Each CO₂ contains one carbon atom.

Related ready-made worksheets: Grade 7 Plant biology worksheet

06

LS Life Sciences

Cells & microscopy

Cells, organelles, microscopes and cell division.

Short lesson: Cells and their components

Study guide for Grades 5 to 8: 4 key ideas, including cell, membrane and nucleus; 2 worked examples and 3 practice questions. Match structures to functions without implying every cell is identical.

  • Cell. Cells are basic structural and functional units of living organisms.
  • Membrane. A cell membrane helps regulate exchange with the surroundings.
  • Nucleus. A typical eukaryotic nucleus contains most of the cell’s DNA; prokaryotes lack a membrane-bound nucleus.
  • Organelles. Mitochondria, chloroplasts and vacuoles have different roles and are not found in the same form in every cell.

Worked example

Which structure forms a selective boundary around a cell?

The membrane regulates exchange with the surroundings.

Answer: Cell membrane.

Read the full study guide

Worksheets

A practice worksheet and a review worksheet, 12 and 12 questions.

Worksheets (PDF)Answer keys (PDF)
Practice worksheet: 12 questions

  1. A printed image is 2 mm long at 200× magnification. Find the actual length in micrometers. Round to 3 decimal places if needed. Answer in µm.

  2. Why must image size and actual size use matching units in a magnification ratio?

    1. Otherwise the numerical ratio is wrong.
    2. Only for colored pictures.
    3. Because units have no meaning.

  3. Which organelle is a site of photosynthesis in many plant cells?

    1. Chloroplast.
    2. Animal lysosome.
    3. Ribosome.

  4. A printed image is 76 mm long at 50× magnification. Find the actual length in micrometers. Round to 3 decimal places if needed. Answer in µm.

  5. An object is 20 µm long and its image is 2000 µm long. Find magnification.

  6. Which structure forms a selective boundary around a cell?

    1. Only the nucleus.
    2. Only the chromosome.
    3. Cell membrane.

  7. A printed image is 27 mm long at 50× magnification. Find the actual length in micrometers. Round to 3 decimal places if needed. Answer in µm.

  8. A 50 µm scale bar is 2 cm long on a print. An object is 6 cm long on the same print. Find its actual length.

  9. Do all cells have a membrane-bound nucleus?

    1. Only all bacteria do.
    2. No; prokaryotic cells do not.
    3. Yes, without exceptions.

  10. A printed image is 70 mm long at 500× magnification. Find the actual length in micrometers. Round to 3 decimal places if needed. Answer in µm.

  11. Convert 0.4 mm to micrometers.

  12. Which statement is most accurate?

    1. Every cell has the same shape and number of organelles.
    2. Different cell types can have different structures and functions.
    3. Cells contain no chemical reactions.
Answer key
  1. 10 µm actual size (µm) = image size (mm) × 1000 / magnification 2 × 1000/200 = 10
  2. Otherwise the numerical ratio is wrong. Magnification is a dimensionless ratio of comparable lengths.
  3. Chloroplast. Chloroplasts contain photosynthetic machinery.
  4. 1520 µm actual size (µm) = image size (mm) × 1000 / magnification 76 × 1000/50 = 1520
  5. 100 2000/20 = 100 times.
  6. Cell membrane. The membrane regulates exchange with the surroundings.
  7. 540 µm actual size (µm) = image size (mm) × 1000 / magnification 27 × 1000/50 = 540
  8. 150 µm The object is three scale-bar lengths: 3 × 50 = 150 µm.
  9. No; prokaryotic cells do not. A membrane-bound nucleus is a eukaryotic feature.
  10. 140 µm actual size (µm) = image size (mm) × 1000 / magnification 70 × 1000/500 = 140
  11. 400 µm 0.4 × 1000 = 400 µm.
  12. Different cell types can have different structures and functions. Specialization produces structural and functional differences.
Review worksheet: 12 questions

  1. A printed image is 73 mm long at 500× magnification. Find the actual length in micrometers. Round to 3 decimal places if needed. Answer in µm.

  2. Why does a scale bar often remain reliable when an image is resized proportionally?

  3. Which structure makes proteins from amino acids using genetic instructions?

    1. Starch grain.
    2. Ribosome.
    3. Cell wall only.

  4. A printed image is 40 mm long at 100× magnification. Find the actual length in micrometers. Round to 3 decimal places if needed. Answer in µm.

  5. Why can digitally enlarging an image fail to show new cellular detail?

  6. Why should chloroplasts not be added to every animal-cell diagram?

  7. A printed image is 77 mm long at 400× magnification. Find the actual length in micrometers. Round to 3 decimal places if needed. Answer in µm.

  8. Which term means distinguishing two nearby points?

    1. Only magnification.
    2. Specimen color.
    3. Resolution.

  9. Why is a cell drawing a model rather than a literal picture of every cell?

  10. A printed image is 46 mm long at 40× magnification. Find the actual length in micrometers. Round to 3 decimal places if needed. Answer in µm.

  11. At 200× magnification, an image is 10 mm long. Find the actual length in millimeters.

  12. A model tissue has 5 equal rows of 6 cells. How many cells are modeled?

Answer key
  1. 146 µm actual size (µm) = image size (mm) × 1000 / magnification 73 × 1000/500 = 146
  2. The bar and specimen image enlarge or shrink by the same factor. The relative lengths are retained.
  3. Ribosome. Ribosomes carry out translation.
  4. 400 µm actual size (µm) = image size (mm) × 1000 / magnification 40 × 1000/100 = 400
  5. It may enlarge existing pixels without improving the captured resolution. Bigger does not necessarily mean more information.
  6. Animal cells do not normally have chloroplasts. Compare cell types instead of copying all organelles into every model.
  7. 192.5 µm actual size (µm) = image size (mm) × 1000 / magnification 77 × 1000/400 = 192.5
  8. Resolution. Resolution concerns detail separation.
  9. Cell types differ, and diagrams simplify scale, shape and contents. State a relevant limitation.
  10. 1150 µm actual size (µm) = image size (mm) × 1000 / magnification 46 × 1000/40 = 1150
  11. 0.05 mm 10/200 = 0.05 mm.
  12. 30 5 × 6 = 30.

Related ready-made worksheets: Grade 7 Cells & microscopy worksheet

07

LS Life Sciences

Ecology & populations

Ecosystems, food webs, populations and biodiversity.

Short lesson: Food-web transfer model

Study guide for Grades 7 to 11: 2 worked examples and 2 practice questions. Convert the supplied transfer efficiency to a fraction. Do not assume that all food webs have a fixed 10% efficiency.

transferred energy = available energy × stated efficiency/100

Convert the supplied transfer efficiency to a fraction. Do not assume that all food webs have a fixed 10% efficiency.

Worked example

A supplied food-web model transfers 10% of 524 kJ to the next level. Find transferred energy. The stated efficiency is not a universal ecological constant. Round to 3 decimal places if needed. Answer in kJ.

transferred energy = available energy × stated efficiency/100 524 × 10/100 = 52.4

Answer: 52.4 kJ

Read the full study guide

Worksheets

A practice worksheet and a review worksheet, 12 and 12 questions.

Worksheets (PDF)Answer keys (PDF)
Practice worksheet: 12 questions

  1. A supplied food-web model transfers 11% of 1433 kJ to the next level. Find transferred energy. The stated efficiency is not a universal ecological constant. Round to 3 decimal places if needed. Answer in kJ.

  2. Should a fixed 10% transfer rule be used as an exact value for every ecosystem?

    1. Only when the diagram has ten arrows.
    2. No.
    3. Yes, without variation.

  3. A supplied food-web model transfers 16% of 251 kJ to the next level. Find transferred energy. The stated efficiency is not a universal ecological constant. Round to 3 decimal places if needed. Answer in kJ.

  4. Which is a primary producer in this simple land food chain?

    1. Grass.
    2. Rabbit.
    3. Fox.

  5. A supplied food-web model transfers 18% of 711 kJ to the next level. Find transferred energy. The stated efficiency is not a universal ecological constant. Round to 3 decimal places if needed. Answer in kJ.

  6. What is a decomposer's role in a simple nutrient model?

    1. Breaking down organic material and helping recycle nutrients.
    2. Stopping every chemical reaction.
    3. Creating new atoms from nothing.

  7. A supplied food-web model transfers 12% of 762 kJ to the next level. Find transferred energy. The stated efficiency is not a universal ecological constant. Round to 3 decimal places if needed. Answer in kJ.

  8. Using the stated convention, grass → rabbit means what?

    1. The rabbit obtains energy by eating grass.
    2. Grass eats the rabbit.
    3. The arrow means both are identical.

  9. A supplied food-web model transfers 8% of 589 kJ to the next level. Find transferred energy. The stated efficiency is not a universal ecological constant. Round to 3 decimal places if needed. Answer in kJ.

  10. A stated model transfers 20% of 500 energy units to the next level. How many units are transferred?

  11. A supplied food-web model transfers 22% of 591 kJ to the next level. Find transferred energy. The stated efficiency is not a universal ecological constant. Round to 3 decimal places if needed. Answer in kJ.

  12. Why is a food web often more realistic than one chain?

    1. Organisms can have multiple feeding relationships.
    2. Every predator eats exactly one species.
    3. Only one organism exists in nature.
Answer key
  1. 157.63 kJ transferred energy = available energy × stated efficiency/100 1433 × 11/100 = 157.63
  2. No. Transfer efficiencies vary; use the stated data.
  3. 40.16 kJ transferred energy = available energy × stated efficiency/100 251 × 16/100 = 40.16
  4. Grass. Grass produces organic matter using photosynthesis.
  5. 127.98 kJ transferred energy = available energy × stated efficiency/100 711 × 18/100 = 127.98
  6. Breaking down organic material and helping recycle nutrients. Decomposition transfers matter into reusable forms.
  7. 91.44 kJ transferred energy = available energy × stated efficiency/100 762 × 12/100 = 91.44
  8. The rabbit obtains energy by eating grass. The arrow points toward the energy recipient.
  9. 47.12 kJ transferred energy = available energy × stated efficiency/100 589 × 8/100 = 47.12
  10. 100 0.20 × 500 = 100; the efficiency is supplied, not assumed universal.
  11. 130.02 kJ transferred energy = available energy × stated efficiency/100 591 × 22/100 = 130.02
  12. Organisms can have multiple feeding relationships. A web allows connected pathways.
Review worksheet: 12 questions

  1. A supplied food-web model transfers 5% of 1334 kJ to the next level. Find transferred energy. The stated efficiency is not a universal ecological constant. Round to 3 decimal places if needed. Answer in kJ.

  2. Why is it misleading to say energy cycles in exactly the same way as carbon atoms?

  3. A supplied food-web model transfers 10% of 613 kJ to the next level. Find transferred energy. The stated efficiency is not a universal ecological constant. Round to 3 decimal places if needed. Answer in kJ.

  4. Why can removing one species affect more than one part of a food web?

  5. A supplied food-web model transfers 19% of 1099 kJ to the next level. Find transferred energy. The stated efficiency is not a universal ecological constant. Round to 3 decimal places if needed. Answer in kJ.

  6. A supplied food-web model transfers 25% of 967 kJ to the next level. Find transferred energy. The stated efficiency is not a universal ecological constant. Round to 3 decimal places if needed. Answer in kJ.

  7. A supplied food-web model transfers 6% of 1086 kJ to the next level. Find transferred energy. The stated efficiency is not a universal ecological constant. Round to 3 decimal places if needed. Answer in kJ.

  8. A supplied food-web model transfers 17% of 1112 kJ to the next level. Find transferred energy. The stated efficiency is not a universal ecological constant. Round to 3 decimal places if needed. Answer in kJ.

  9. A supplied food-web model transfers 15% of 815 kJ to the next level. Find transferred energy. The stated efficiency is not a universal ecological constant. Round to 3 decimal places if needed. Answer in kJ.

  10. A supplied food-web model transfers 15% of 200 kJ to the next level. Find transferred energy. The stated efficiency is not a universal ecological constant. Round to 3 decimal places if needed. Answer in kJ.

  11. A supplied food-web model transfers 18% of 897 kJ to the next level. Find transferred energy. The stated efficiency is not a universal ecological constant. Round to 3 decimal places if needed. Answer in kJ.

  12. A supplied food-web model transfers 14% of 822 kJ to the next level. Find transferred energy. The stated efficiency is not a universal ecological constant. Round to 3 decimal places if needed. Answer in kJ.

Answer key
  1. 66.7 kJ transferred energy = available energy × stated efficiency/100 1334 × 5/100 = 66.7
  2. Energy is transferred and dissipated, while atoms can be reused across chemical forms. Distinguish energy flow from matter cycling.
  3. 61.3 kJ transferred energy = available energy × stated efficiency/100 613 × 10/100 = 61.3
  4. Multiple organisms are linked through feeding and other interactions. Trace at least one connected consequence.
  5. 208.81 kJ transferred energy = available energy × stated efficiency/100 1099 × 19/100 = 208.81
  6. 241.75 kJ transferred energy = available energy × stated efficiency/100 967 × 25/100 = 241.75
  7. 65.16 kJ transferred energy = available energy × stated efficiency/100 1086 × 6/100 = 65.16
  8. 189.04 kJ transferred energy = available energy × stated efficiency/100 1112 × 17/100 = 189.04
  9. 122.25 kJ transferred energy = available energy × stated efficiency/100 815 × 15/100 = 122.25
  10. 30 kJ transferred energy = available energy × stated efficiency/100 200 × 15/100 = 30
  11. 161.46 kJ transferred energy = available energy × stated efficiency/100 897 × 18/100 = 161.46
  12. 115.08 kJ transferred energy = available energy × stated efficiency/100 822 × 14/100 = 115.08

Related ready-made worksheets: Grade 7 Ecology & populations worksheet

08

ESS Earth and Space Sciences

Earth & space

The Sun, Moon and planets, day and night, the water cycle and Earth's layers.

Short lesson: Earth systems

Study guide for Grades 4 to 9: 20 key ideas, including crust, mantle and outer core; 3 practice questions.

Weathering breaks material down; erosion transports it. These processes can happen together, but they are not the same.

  • Crust. Earth's thin outermost solid rocky layer.
  • Mantle. The thick rocky region between Earth's crust and core.
  • Outer core. The mostly liquid metallic layer surrounding Earth's inner core.
  • Inner core. Earth's solid central metallic region.

Read the full study guide

Worksheets

A practice worksheet and a review worksheet, 12 and 12 questions.

Worksheets (PDF)Answer keys (PDF)
Practice worksheet: 12 questions

  1. Earth systems: which term fits this description? The model describing movement and interaction of Earth's lithospheric plates.

    1. Lava
    2. Plate tectonics
    3. Erosion
    4. Precipitation

  2. Space and the solar system: which term fits this description? The star at the centre of our solar system.

    1. Orbit
    2. Revolution
    3. Uranus
    4. Sun

  3. What process forms an igneous rock in the basic model?

    1. Cooling and solidification of molten material.
    2. Every type of evaporation.
    3. Only compacting plastic litter.

  4. When the Northern Hemisphere tilts toward the Sun, the Southern Hemisphere generally has

    1. winter
    2. no gravity
    3. the same summer at the same time
    4. no daylight anywhere

  5. Which two natural influences help drive water movement through the cycle?

    1. compass needles and maps
    2. sound and handwriting
    3. solar energy and gravity
    4. paint and glue

  6. One unusually cold day disproves a long-term warming trend. Is this valid?

    1. Only if it was a Monday.
    2. Only if it snowed.
    3. Yes, always.
    4. No; one day is not a long-term pattern.

  7. What does one orbital revolution correspond to in the basic Earth model?

    1. One year.
    2. One ordinary hour.
    3. One lunar crater.

  8. Earth systems: which term fits this description? Water stored in saturated spaces beneath the ground.

    1. Lava
    2. Igneous rock
    3. Groundwater
    4. Outer core

  9. Space and the solar system: which term fits this description? The planet closest to the Sun.

    1. Jupiter
    2. Solar eclipse
    3. Mercury
    4. Light-year

  10. Why can a rock contain several different minerals?

  11. The Moon is visible mainly because it

    1. burns like a star
    2. reflects only city lights
    3. has electric lamps
    4. reflects sunlight

  12. Water flowing over the land after rain is

    1. a magnetic field
    2. a phase of the Moon
    3. runoff
    4. a chemical element
Answer key
  1. Plate tectonics Plate tectonics: The model describing movement and interaction of Earth's lithospheric plates.
  2. Sun Sun: The star at the centre of our solar system.
  3. Cooling and solidification of molten material. Igneous rock forms from magma or lava cooling.
  4. winter The hemispheres receive different seasonal sunlight conditions.
  5. solar energy and gravity Solar energy supports evaporation, and gravity moves water downward.
  6. No; one day is not a long-term pattern.
  7. One year. Earth's orbital period defines the year-scale cycle.
  8. Groundwater Groundwater: Water stored in saturated spaces beneath the ground.
  9. Mercury Mercury: The planet closest to the Sun.
  10. Rocks can be aggregates of multiple mineral components. Rock and mineral are not interchangeable terms.
  11. reflects sunlight Sunlight reflected from its surface reaches us.
  12. runoff Runoff travels across the surface.
Review worksheet: 12 questions

  1. Earth systems: which term fits this description? Molten rock that has reached Earth's surface.

    1. Weathering
    2. Lava
    3. Weather
    4. Climate

  2. Space and the solar system: which term fits this description? The path an object follows as it moves under gravity around another object.

    1. Venus
    2. Comet
    3. Solar eclipse
    4. Orbit

  3. Which is a sound safety rule for a classroom Sun discussion?

    1. Never look directly at the Sun without appropriate certified protection and expert guidance.
    2. Use binoculars with no filter.
    3. Look longer when it is bright.
    4. Stare at it through ordinary sunglasses.

  4. Why should the same rainfall units be used in a comparison chart?

  5. How could paving a previously grassy area change the route taken by rainwater?

  6. Why should a field observation be recorded before choosing a rock name?

  7. What primarily explains the opposite seasons of the two hemispheres?

    1. Every location being closer to the Sun in its summer.
    2. Axial tilt relative to the orbital plane.
    3. The Moon blocking all winter light.

  8. Earth systems: which term fits this description? Long-term patterns and statistics of weather in a region.

    1. Climate
    2. Weather
    3. Mantle
    4. Lava

  9. Space and the solar system: which term fits this description? An event in which the Moon passes into Earth's shadow.

    1. Lunar eclipse
    2. Light-year
    3. Milky Way
    4. Venus

  10. Waxing describes a visible illuminated portion that is

    1. increasing
    2. always absent
    3. permanently frozen
    4. decreasing

  11. Liquid water becoming water vapour is

    1. condensation
    2. sedimentation
    3. evaporation
    4. melting

  12. Which is a place where water can be stored?

    1. a wind direction
    2. an aquifer
    3. a shadow
    4. a temperature scale
Answer key
  1. Lava Lava: Molten rock that has reached Earth's surface.
  2. Orbit Orbit: The path an object follows as it moves under gravity around another object.
  3. Never look directly at the Sun without appropriate certified protection and expert guidance. Unprotected solar viewing can damage eyes; use safe indirect classroom models instead.
  4. Consistent units prevent a numerical difference caused only by different unit scales.
  5. It may reduce infiltration and increase or redirect surface runoff, depending on drainage. Avoid claiming that all rain follows one route.
  6. Texture, composition and context provide evidence for classification. Use evidence rather than guessing from one color.
  7. Axial tilt relative to the orbital plane. Tilt changes sunlight angle and day length differently in the hemispheres.
  8. Climate Climate: Long-term patterns and statistics of weather in a region.
  9. Lunar eclipse Lunar eclipse: An event in which the Moon passes into Earth's shadow.
  10. increasing Waxing refers to the growing lit fraction seen from Earth.
  11. evaporation
  12. an aquifer Groundwater can occupy pores and fractures underground.

Related ready-made worksheets: Grade 7 Earth & space worksheet