CBSE Sample Papers for Class 8 Science Practice Paper 3

Test Paper III
Class VIII

Time : 2 1/2 Hrs                                                                                                     Maximum Marks : 100 

General Instructions:

  1. Read the content of the question carefully and attempt them there after.
  2. Follow the specified word limit, wherever mentioned.
  3. Try to be brief and concise and have clarity in expression.
  4. Make diagrams and figures wherever necessary.

1. Fill in the blanks:                                                                                                1 x 10 = 10               

  1. The process of beating out the grains from the harvested crop plants is
    called………….
  2. The yolk is surrounded by a white portion called………….
  3. The growing of plants (or crops) in the fields for obtaining food is called………….
  4. The flow of electrons in the wire constitutes an ………….
  5. The space around a magnet in which it can exert force on magnetic objects like
    iron and steel is called its………….
  6. …………is a ceramic material containing iron along with cobalt, nickel or zinc.
  7. ………….are microscopic single called algae whose cell walls are made of silica.
  8. ………….is a fungus commonly known as bread mould.
  9. ………….is a parasitic protozoan and cause a disease called malaria.
  10. The………….is a complex mixture of a large number of hydrocarbons.

2. Give one word answer of the following questions:                                1 x 10 = 10             

  1. A device which is used to test the purity of milk.
  2. The process of separating grain from chaff and hay with the help of wind.
  3. The removal of anthers from the flowers of a plant to prevent self pollination.
  4. The process of transfering the seedlings from the nursery to the main field by hand.
  5. Machine used to remove honey from honey comb.
  6. The rearing of bees for obtaining honey.
  7. Scientist who invented the dry cell.
  8. Another name of blue green algae.
  9. The process by which yeast reproduces.
  10. A fungi used as a food.

3. Give reasons:                                                                                                         2 x 5 = 10               

  1. Virus particle not considered to be a cell. Why?
  2. We use iron for making an electromagnet and not steel. Why?
  3. Farmers carry out lavelling of the ploughed field. Why?
  4. Weeds multiply and spread very fast. Why?
  5. A person having acidity is given milk of magnesia. Why?

4.Answer the following questions:                                                                     2 x 5 = 10               

  1. What js pisiculture? How are fish reared by pisiculture?
  2. Give two broad groups of cattle feed. Give their constitutions.
  3. What are the two types of crops based on seasons? Give two examples for both.
  4. What is meant by electromagnetic induction? Name the two scientists discovered the effect of it.
  5. What are mycoplasmas? Name two diseases caused by mycoplasmas.

5.Difference between the following pair with example:                       2 1/2 x 4 = 10

  1. Manure and fertiliser
  2. Drycell and storage cell
  3. Conductors and insulators
  4. Gram positive and Gram negative bacteria.

6.Define following with diagram (any four)                                           2 1/2 x 4 = 10

  1. Electromagnet
  2. Magnetic compass
  3. Electric circuit
  4. Protozoan
  5. Yeast

7. Answer any two of following questions:                                                      5 x 2= 10

  1. You are given two similar steel bars, one of which is a magnet. What else would you require to test which of the given steel bar is a magnet?
  2. What are the various types of bacteria? Give shape and one example of each.
  3. How will you find out whether an egg is
    (a) fertilised or unfertilised?
    (b) spoiled or good eggs?

8.Give the answer of the following:

  1. Name two high yielding breeds/varities of the following:                       1 x 5 = 5
    (a) Cow (b) Buffalo (c) Hen (d) Wheat (e) Paddy.
  2. Write the full form of the following:                                                                1 x 5 = 5
    (a) KVIC (b) DDT (c) BHC (d) TMV (e) RNA.
  3. Name the types of chemical reaction:                                                              1 x 5 = 5
    cbse-class-8-science-practice-paper-3-1
  4. Name the disease causing microorganism:                                                   1 x 5 = 5
    (a) Food poisoning     (b) AIDS (c) Measles
    (d) Sleeping sickness (e) Ring worm.
  5. Draw the electric symbol of the following:                                                     1 x 5 = 5
    (a) Dry cell            (b) Battery     (c) Electric bulb
    (d) Switch open   (e) Connecting wire.
  6. Draw anyone labelled diagram:                                                                                               (a) Fractionating Tower (b) Dry cell