CBSE Class 5 EVS Water Worksheet

Ques 1) Answer the following questions in detail.

Question a). Write the difference between a Well and Step Well (give an example wherever applicable).
Answer: A traditional well is a deep hole dug in the ground to reach underground water, usually pulled up using a bucket and rope or a pulley system. A step well (known as a baoli) is a deep water source surrounded by intricate stone steps descending to the water level, allowing people to walk down directly to fetch water or use it as a cool gathering place during hot weather. Example: Rani ki vav in Gujarat is a famous step well.
In simple words: A regular well is a deep pit with water pulled up by a rope, while a step well has stairs leading all the way down to the water.

Exam Tip: Remember that step wells served social and cultural purposes in ancient times in addition to providing water storage.

Question b). Write about the following - i)
Answer: The image shows a Persian wheel (rahat), which is a traditional mechanical device used for irrigation. It consists of a vertical wheel with buckets attached to it, turned by a draft animal (like an ox or bullock) walking in a circle. As the wheel rotates, it lifts water from a well or water source to irrigate nearby fields.
In simple words: It is a bullock-driven water wheel used to lift water from wells for watering crops.

Exam Tip: Mention the role of animals in powering traditional agricultural equipment like the Persian wheel.

Question b). Write about the following - ii)
Answer: The image depicts a public drinking water station or community water arrangement (piao), where earthen pots (matkas) are kept to provide cool drinking water to travelers and the general public, especially during hot summer months.
In simple words: It is a public water station with earthen pots for thirsty travelers.

Exam Tip: Earthen pots naturally cool water through evaporation, which is why they are traditionally used in communities.

Question b). Write about the following - iii)
Answer: The image shows a handpump, which is a manually operated pump used to draw groundwater from a shallow underground aquifer. By moving the long handle up and down, a piston creates suction that draws water up through a pipe.
In simple words: A handpump is a manual device operated by hand to pump out underground water.

Exam Tip: Handpumps are common in rural and semi-urban areas as a reliable source of drinking water.

Question c). Write about the three types of irrigation.
Answer: The three main types of irrigation are:
1. Surface Irrigation: Water flows over and across the land by gravity, flooding the fields or moving through small channels and furrows.
2. Sprinkler Irrigation: Water is piped to one or more central locations in the field and sprayed overhead across the crops using high-pressure sprinklers, mimicking natural rainfall.
3. Drip Irrigation: Water is delivered drop by drop directly to the roots of plants through a network of valves, pipes, and small emitters, minimizing water wastage.
In simple words: The three types are surface irrigation (flooding fields), sprinkler irrigation (spraying like rain), and drip irrigation (giving water drop by drop to roots).

Exam Tip: Drip irrigation is the most water-efficient method and is widely recommended in dry regions.

Question d). Define habitat. Complete the following table-
Answer: A habitat is the natural home or environment of an animal, plant, or other organism where it naturally lives, grows, and reproduces.

In simple words: A habitat is an organism's natural home. Organisms can be grouped based on whether they live on land, in water, on trees, or both on land and water.
Exam Tip: Always provide matching, accurate examples for each habitat category in tables.

Question e). Write the differences between (give an example wherever applicable)
Answer: The images show three types of aquatic plants based on their habitat and growth:
1. Free-floating Aquatic Plants: These plants float freely on the surface of the water and are not anchored to the soil. Their roots hang loosely in the water to absorb nutrients. Example: Water Hyacinth (Pistia / Eichhornia).
2. Floating-leaved (Rooted with floating leaves) Aquatic Plants: These plants have their roots fixed in the soil at the bottom of the water body, while their broad leaves and flowers float on the water surface. Example: Lotus or Water Lily.
3. Submerged Aquatic Plants: These plants grow completely underwater with their roots anchored in the mud. They have thin, ribbon-like or narrow leaves that allow water to flow past them easily. Example: Hydrilla or Tape Grass.
In simple words: Aquatic plants can be floating (free on top), floating-leaved (rooted below with leaves on top), or submerged (completely underwater).

Exam Tip: Categorize aquatic plants clearly by the position of their roots and leaves relative to the water surface.

Question f). How are the following different from each other?
Answer: The images show a Great White Shark (a fish) and a Dolphin (a marine mammal):
1. Breathing: Sharks breathe dissolved oxygen in water using gills, whereas dolphins are mammals that breathe air through lungs using a blowhole on top of their head and must surface periodically.
2. Skeleton: Sharks have a skeleton made entirely of cartilage, whereas dolphins have a bony skeleton.
3. Reproduction: Sharks either lay eggs or give birth to live young depending on the species, while dolphins give birth to live young and feed them milk.
In simple words: Sharks are fish that breathe through gills and have cartilaginous skeletons, while dolphins are warm-blooded mammals that breathe air through lungs.

Exam Tip: Never mistake a dolphin for a fish; remember dolphins are marine mammals that nurse their young.

Question g). Explain the process of purification of water in a water treatment plant with the help of a flowchart.
Answer:
Source Water (River/Lake) -> Screening (Removal of large floating objects) -> Sedimentation (Settling of heavy suspended impurities in tanks) -> Filtration (Passing through layers of sand and gravel to remove fine particles) -> Chlorination/Disinfection (Adding chlorine to kill harmful germs and bacteria) -> Storage & Distribution (Clean water pumped to homes)
In simple words: Water goes through screening, settling, filtering, and adding chlorine to kill germs before reaching our taps.

Exam Tip: Memorize the correct sequence of steps in water treatment: Screening, Sedimentation, Filtration, and Chlorination.

Question h). Why is man a threat to aquatic life? Write about the three causes of water pollution.
Answer: Man is a major threat to aquatic life because human activities continuously contaminate water bodies, destroy natural habitats, and deplete dissolved oxygen essential for marine and freshwater organisms. Three main causes of water pollution are:
1. Industrial Waste: Factories discharge toxic chemicals, heavy metals, and acids directly into rivers and oceans without proper treatment.
2. Sewage and Domestic Waste: Untreated sewage, household detergents, and garbage from cities and towns are dumped into water bodies, promoting harmful algal blooms and spreading diseases.
3. Agricultural Runoff: Excessive use of chemical fertilizers, pesticides, and insecticides washes into rivers and lakes, causing eutrophication and poisoning aquatic organisms.
In simple words: Humans pollute water through factory waste, raw sewage, and chemical runoff from farms, which destroys aquatic life.

Exam Tip: Clearly list industrial waste, sewage, and agricultural chemicals as the primary drivers of water pollution.

Question i). Label the various parts of a fish.
Answer: Based on the standard anatomical diagram of a fish, the labeled parts are:
- Top left box: Mouth
- Middle left box: Nostril
- Upper left arrow: Eye
- Bottom left box: Pelvic fin
- Bottom middle box: Anal fin
- Top right boxes: Dorsal fins (First dorsal fin and Second dorsal fin)
- Bottom right box: Tail fin (Caudal fin)
In simple words: A fish has fins for swimming, gills for breathing, eyes, and a mouth.

Exam Tip: Practice labeling fins correctly (dorsal, pelvic, anal, caudal) as they serve different functions like balance and steering.

Ques 2) Define (give examples wherever applicable)-

Question a). Weeds
Answer: Weeds are unwanted, undesirable plants that grow naturally in places where they are not wanted, such as in cultivated crop fields or gardens, competing with main crops for sunlight, water, and nutrients. Example: Amaranth or wild grass.
In simple words: Weeds are unwanted wild plants growing among crops.

Exam Tip: State that weeds compete with useful plants for resources.

Question b). Canals
Answer: Canals are man-made channels or artificial waterways dug out of land to transport water from rivers, lakes, or reservoirs for irrigation, navigation, and water supply. Example: Indira Gandhi Canal in India.
In simple words: Canals are artificial water channels built to bring water to dry areas.

Exam Tip: Emphasize that canals are man-made water transport routes.

Question c). Electric Ray
Answer: An electric ray is a flat-bodied cartilaginous marine fish belonging to the order Torpediniformes, capable of producing a powerful electric discharge from specialized electric organs to stun prey or defend against predators.
In simple words: An electric ray is a flat sea fish that can produce electricity to stun its prey.

Exam Tip: Mention the specialized electric organs used for defense and hunting.

Question d). Tubewells
Answer: A tubewell is a type of water well in which a long, wide stainless steel or plastic pipe or tube 10-20 centimeters in diameter is bored 30 to 300 meters deep into an underground aquifer, and water is pumped out mechanically using an electric or diesel pump.
In simple words: A tubewell is a deep drilled pipe fitted with a pump to draw out underground water.

Exam Tip: Differentiate tubewells from handpumps by noting that tubewells use electric or diesel pumps for deeper water extraction.

Question e). Climbing fish
Answer: A climbing fish is a specialized freshwater fish equipped with accessory breathing organs that allow it to absorb oxygen directly from the air and move across damp land or climb low tree roots when its water body dries up. Example: Anabas testudineus (Climbing Perch).
In simple words: A climbing fish can breathe air and travel short distances across land.

Exam Tip: Mention their ability to survive out of water using special breathing organs.

Question f). Irrigation
Answer: Irrigation is the agricultural process of artificially applying controlled amounts of water to land to assist in the cultivation and growth of crops, especially during periods of inadequate rainfall or drought.
In simple words: Irrigation is supplying water to crops artificially.

Question g). Fusilier Fish
Answer: Fusilier fish are small, colorful, fast-swimming marine schooling fish belonging to the family Caesionidae, commonly found in tropical Indo-Pacific coral reefs and known for feeding on plankton in mid-water columns.
In simple words: Fusilier fish are small, colorful schooling fish found near coral reefs.

Exam Tip: Associate fusilier fish with coral reef ecosystems and schooling behavior.

Question h). Frogs and toads
Answer: Frogs and toads are amphibians belonging to the order Anura. Frogs typically have smooth, moist skin and long legs adapted for leaping, while toads generally have dry, warty skin and shorter legs adapted for crawling or hopping, spending part of their lives in water and part on land.
In simple words: Frogs and toads are tailless amphibians; frogs have smooth wet skin while toads have dry warty skin.

Exam Tip: Highlight skin texture and leg length as key differences between frogs and toads.

Question i). Turtles and crabs
Answer: Turtles are reptiles with a bony or cartilaginous shell developed from their ribs that acts as a shield, living mostly in water or on land. Crabs are decapod crustaceans with a thick exoskeleton and a single pair of pincers, commonly found inhabiting coastal marine, freshwater, or terrestrial environments.
In simple words: Turtles are shelled reptiles and crabs are hard-shelled crustaceans with pincers.

Exam Tip: Classify turtles correctly as reptiles and crabs as crustaceans.