Water Cycle Comprehension Worksheet
Earth Science • Reading Comprehension CK-12 FlexBook Aligned
The Water Cycle: Comprehension Guide
Processes & Reservoirs
Total Score: 25 Pts
Name:
Date:
Period:
Directions: Read the passage "The Water Cycle" thoroughly. Use specific evidence, key vocabulary, and details from the text to answer each question below.
A
Part 1: Key Concepts & Energy Drivers (Questions 1–4)
- According to the text, what fundamental source of energy powers the continuous movement of Earth's water cycle?
A Geothermal heat from Earth's core
B Radiant energy from the Sun
C Ocean tides created by the Moon
D Prevailing atmospheric wind currents
- Why does the majority of all evaporation on Earth occur from the oceans rather than from freshwater lakes, rivers, or land?
A Saltwater evaporates at a significantly lower temperature
B Oceans cover the vast majority of Earth's surface area
C Deep ocean currents generate extreme heat at the surface
D Marine plant life pushes extra water vapor into the air
- According to the text, in what exact way is transpiration like standard evaporation?
A Both change liquid water into gaseous water vapor
B Both require living plant leaves to release moisture
C Both take place deep beneath Earth's soil layers
D Both cause liquid water to freeze into ice crystals
- What atmospheric condition causes rising water vapor to condense into liquid cloud droplets?
A Air warms up as it climbs higher above ground level
B Air cools as it rises, and cooler air holds less water vapor
C Lower atmospheric friction splits gas molecules into liquids
D Ultraviolet solar rays fuse gas molecules into raindrops
CK-12 Earth Science • The Water Cycle Page 1 of 2
Student Assessment The Water Cycle • Part 2 & Part 3
Name:
B
Part 2: Surface Movement & Earth Reservoirs (Questions 5–7)
- When water droplets in clouds become too large to stay aloft, precipitation falls. Where does most precipitation land?
A Directly back into Earth's oceans
B Over high mountain snowpacks
C Across inland forests and grasslands
D Into freshwater lakes and river basins
- What process describes water soaking into the ground to stay in the soil or seep deep underground?
A Infiltration
B Transpiration
C Surface Runoff
D Sublimation
- According to the text, how can runoff negatively affect bodies of water like rivers, lakes, and oceans?
A It causes lakes to evaporate prematurely
B It picks up fertilizer and pollutants, delivering them to water bodies
C It strips oxygen from the air as it moves over soil
D It permanently traps water molecules deep inside the crust
C
Part 3: Explanations & Systems Thinking (Questions 8–10)
Complete sentences required
- Analogy Analysis: Figure 4 shows condensation on a cold glass of ice water. Explain why water droplets form on the glass, and describe how this is the exact same process that creates clouds in the sky.
4 Pts
- Constant Recycling: The text notes that the water cycle has "no beginning or end" and that you might drink water once consumed by a dinosaur. Why can water molecules on Earth be recycled continuously for billions of years?
4 Pts
- Plant Pathways: Trace a water molecule through a plant: How is it absorbed from the ground, through what plant structure and process does it enter the atmosphere, and what must occur for it to return to Earth?
5 Pts
Review all answers for clarity and text evidence Page 2 of 2
Water Cycle Answer Key
Teacher Edition • Answer Key & Scoring Guide CK-12 FlexBook Aligned
The Water Cycle: Answer Key
Total: 25 Points
Standards: NGSS MS-ESS2-4
1
Part 1 (Q1–4) MC: 2 pts each (8 pts)
2
Part 2 (Q5–7) MC: 2 pts each (4 pts + 1 pt / scaled)
3
Part 3 (Q8–10) Written: 13 pts (Q8: 4, Q9: 4, Q10: 5)
A
Part 1: Key Concepts & Energy Drivers (Questions 1–4)
2 Pts Each
- Fundamental source of energy powering Earth's water cycle:
B
Correct Option: B — Radiant energy from the Sun
Teacher Rationale & Misconception: The Sun provides the thermal radiant energy that heats surface water, driving evaporation and transpiration. Earth's core provides internal heat (volcanism), and tides are governed by gravity, but neither drives atmospheric water circulation.
- Why does the majority of all evaporation on Earth occur from oceans?
B
Correct Option: B — Oceans cover the vast majority of Earth's surface area
Teacher Rationale & Misconception: Oceans cover approximately 71% of Earth's surface and store over 96% of its water. Surface area directly dictates the volume of water molecules escaping into vapor. Dissolved salts actually slightly elevate the boiling point rather than lower it.
- How is transpiration like standard evaporation?
A
Correct Option: A — Both change liquid water into gaseous water vapor
Teacher Rationale & Misconception: Transpiration is biological evaporation through plant stomata. Both processes are physical state transitions (liquid \(\rightarrow\) gas) requiring latent heat of vaporization.
- What atmospheric condition causes rising vapor to condense into clouds?
B
Correct Option: B — Air cools as it rises, and cooler air holds less water vapor
Teacher Rationale & Misconception: As warm air rises, it expands and cools (adiabatic lapse rate). Cold air has a lower saturation point (dew point); excess vapor condenses onto microscopic aerosols into liquid water droplets or ice crystals.
Critical Concept Clarification for Students:
Many students mistakenly believe that clouds are made of invisible water vapor. Emphasize that water vapor is a transparent gas. The moment a cloud becomes visible, the water has already undergone into billions of microscopic or !
