Water (Term 2 Chapter 2 | 5th Science)
I. Choose the correct answer.
1. Which of the following micro organisms causes waterborne diseases?
Answer: d) All
2. Water is present in huge quantities as vapour and clouds in the ________
Answer: c) atmosphere
3. ________ water is free from suspended impurities.
Answer: d) Underground
4. ________ of water is in oceans and seas.
Answer: a) 97%
5. __________ is an artificial process of converting sea water into fresh water.
c) Reverse Osmosis
Answer: d) Desalination
II. Fill in the blanks.
1. The accumulated underground water comes out in the form of spring.
2. The process of changing water into water vapour by the heat of the Sun is called evaporation.
3. Rain water forms streams and springs which join together to form rivers.
4. The process of collecting and storing rain water is called Rain water harvesting.
5. Cholera is caused by Bacteria (Vibrio cholerae).
III. Match the following.
1. Leakage of oil - Cloud
2. Reservoir - Plant growth
3. Distillation - Pollute marine organisms
4. Rainwater harvesting - Influenza virus
5. Swine Flu - Man-made lake
1. Leakage of oil - Pollutes marine organisms
2. Reservoir - Man-made lake
3. Distillation - Cloud
4. Rain water harvesting - Plant growth
5. Swine Flu - Influenza virus
IV. Answer briefly.
1. Write down the sources of water.
The following are the sources of water.
1) River water and lake water
2) Sea water
3) Well water
4) Spring water
5) Underground water.
2. What is desalination?
Desalination is an artificial process of converting saline water (sea water) into fresh water. The common desalination processes are:
* Reverse Osmosis.
3. What are the processes involved in the water cycle?
Water cycle consists of the following four stages.
4. Flowing back to oceans.
4. What are reservoirs?
Man-made lakes created when dam is built on a river is called reservoir.
5. How can we prevent Dengue fever?
* Spray the house with anti-mosquito spray.
* Try to wear clothes that cover skin areas.
* Close the doors and windows during early morning and evening.
* Do not leave stagnant water anywhere in and around the house.
V. Answer in Detail.
1. Write the advantages of rainwater harvesting
* Rain water harvesting can reduce flooding in the cities.
* Rain water harvesting can reduce top soil loss.
* Ground water level can be increased.
* Ground water can be conserved.
* It can improve plant growth.
2. How can we prevent waterborne diseases?
* Good personal hygiene should be practised and basic sanitation should be improved.
* Chlorinated and boiled water should be used for drinking.
* Drink boiled or pasteurized milk.
* Dispose infectious wastes properly.
Take half a glass of water. Clean the outside part of the glass. Add few ice cubes and leave it for 5-10 minutes. You will observe drops of water appearing outside the glass. This happens because the water vapour in the air condenses on the cold surface of the glass.
Estimate the amount of water used by your family in a day for drinking, brushing, bathing, cleaning vessels, washing cloths, toilets and cleaning the floor. Find out for which activity water usage is more and how it can be minimized.
Visit an industry in your area with the help of your teacher. Observe and note the waste water treatment process.
Visit a primary health centre in your area and find out the common waterborne diseases prevalent among the people. Also find out the causes for them.