DAV SCIENCE CLASS IV

Revision A.Q1.which is not a characteristic of insects a)membranous wings b) Six legs c) Body is divided into three parts d) None of these Q2.this is not a social insect a)termite             b) ant    c) honey bee     d) wasp Q3.It is the food of silk worm a)bamboo leaf  b)sugar cane leaf             c)mulberry leaf d)mango leaf Q4.The unfertile female of a bee hives a)       Queen  b) drones            c) Worker            d) none of these Q5.Rearing of silk moth for silk is known as a)       Apiculture           b) sericulture     c)agriculture     ...

Revision-2  Topic : Food A.Choose the most appropriate answer 1. Fruits and vegetable are ……………………….. Food.   (a)body-building                    (b)energy-giving                     (c)protective               (d)roughage 2. Excess …………… gets stored under the skin   (a)protein                  (b)vitamin                   (c)fat               (d)roughage 3. …………… is not a nutrient   (a)protein          ...

EXPRESS IN ONE OR TWO WORD CHAPTER-8,9 AND10 A method for removing dust and other suspended particles from water: Standing or still water: Water fit for drinking: Method of cleaning: Extremely small living beings which can cause diseases: The most common method of purifying water: Our body needs it for proper functioning: The method does not removes germs: It should be put in coolers if water cannot be changed: We should use it to take out water from containers: This kills germs and makes it fit for drinking: Waste produce in homes: In cities people get water from it: Chemicals used to save the crops from birds , rats and insects: Oil leaked from tankers carrying it: Materials used to increase the production of crops: Pipes carrying, carrying sewage, should not be kept near the pipe carrying this: People should not wash clothes, or use soaps if they bath in this: This get infected by pollu...

Water Pollution D1.Name any two materials which can make rain water impure. Ans:Dust and smoke are the  two  materials which pollute the rain water D2.Name two human activities which can cause water pollution? Ans: Washing clothes  and bathing in river or pond pollute the water. D3.Which two pollutants are often dumped by factories into the river? Ans: Harmful chemical and solid waste materials are dumped into the river by the factories. D4.Name any two diseases that can be caused by drinking polluted water. Ans: Two diseases that may causes by drinking polluted water are jaundice and cholera. D5.Write the names of two types material, used by farmers to increase the production of crops. Ans: Pesticides and chemical fertilizer are the two types of material used by farmer   to increase the crop production. E1.How do wastes from factories and fields affect the aquatic animals? Ans: Agricultural and industrial waste increase the number of micro-organism...

SAFE HANDLING AND STORAGE OF WATER D1.State the meaning of the term potable water. Ans: Water which is clean,germ free and fit for drinking is called potable water. D2.Name any two diseases that can be caused by drinking unclean water. Ans:Two diseases that can be caused by drinking unclean water are diarrhea and jaundice D3.Name the diseases which are spread by mosquitoes. Ans:The diseases spread by mosquitoes are malaria, dengue, chikungunya and filaria. D4. How does boiling help in making water safe for drinking? Ans:Boiling kills the germ present in water and make safe for drinking. D5.Name two methods of purification of water. Ans:Two methods of purification of water are boiling and chlorination. D6.Name any two ways of safe handling of drinking water. Ans:Ways of safe handling of drinking water are: i)Water should be stored in clean and covered container. ii)we should not dip our hand in water stored for drinking . iii)We should use ladle...

Food D1.Name the nutrients presents in energy giving foods. Ans:Carbohydrates and fats are the nutrients present in energy giving foods. D2.State the main role of proteins for our body. Ans: Protein help our body to grow and repair the worn –out tissues. D3. Name two food items obtained from animals that are good sources of protein. Ans: Milk and fish are good sources of animal protein . D4. Name the minerals that are required for healthy bones and teeth. Also mention one food source that contains both of them. Ans :Calcium and phosphorous are the minerals required for healthy bones and teeth. Milk is one food source that contains both calcium and phosphorous. D5.Why are vitamins and minerals called protective food? Ans: Vitamins and minerals are a nutrient which protects our body from diseases and keep us healthy. It also protect against infection .food item containing vitamin and minerals are called protective food. E. Answer the following question...

Q.1. Fill in the blanks i)         ……roots have branches ii)        Special roots come out ……………of a banyan tree. iii)      leaf has ………………..to prepare food iv)      …………………are found in cereals v)       In mangrove plant do not get sufficient……………….  in the marshy area. vi)      Reckless cutting of trees is called ………………. vii)    Roots absorb ………………. and …………… for the plant . Q.2. Choose the most appropriate answer (MCQ) i) Which of the following plants has edible root? (a)Rice      (b) Banyans   c) Radish        d) Mangrove ii) Which of the following plants has tap root? (a)Rice      (b) Banyans   c) Grass         d) Mangrove iii) Which of the following plants has...