CBSE Sample Papers for Class 8 Science Practice Paper 3
Test Paper III
Time : 2 1/2 Hrs Maximum Marks : 100
- Read the content of the question carefully and attempt them there after.
- Follow the specified word limit, wherever mentioned.
- Try to be brief and concise and have clarity in expression.
- Make diagrams and figures wherever necessary.
1. Fill in the blanks: 1 x 10 = 10
- The process of beating out the grains from the harvested crop plants is
- The yolk is surrounded by a white portion called………….
- The growing of plants (or crops) in the fields for obtaining food is called………….
- The flow of electrons in the wire constitutes an ………….
- The space around a magnet in which it can exert force on magnetic objects like
iron and steel is called its………….
- …………is a ceramic material containing iron along with cobalt, nickel or zinc.
- ………….are microscopic single called algae whose cell walls are made of silica.
- ………….is a fungus commonly known as bread mould.
- ………….is a parasitic protozoan and cause a disease called malaria.
- The………….is a complex mixture of a large number of hydrocarbons.
2. Give one word answer of the following questions: 1 x 10 = 10
- A device which is used to test the purity of milk.
- The process of separating grain from chaff and hay with the help of wind.
- The removal of anthers from the flowers of a plant to prevent self pollination.
- The process of transfering the seedlings from the nursery to the main field by hand.
- Machine used to remove honey from honey comb.
- The rearing of bees for obtaining honey.
- Scientist who invented the dry cell.
- Another name of blue green algae.
- The process by which yeast reproduces.
- A fungi used as a food.
3. Give reasons: 2 x 5 = 10
- Virus particle not considered to be a cell. Why?
- We use iron for making an electromagnet and not steel. Why?
- Farmers carry out lavelling of the ploughed field. Why?
- Weeds multiply and spread very fast. Why?
- A person having acidity is given milk of magnesia. Why?
4.Answer the following questions: 2 x 5 = 10
- What js pisiculture? How are fish reared by pisiculture?
- Give two broad groups of cattle feed. Give their constitutions.
- What are the two types of crops based on seasons? Give two examples for both.
- What is meant by electromagnetic induction? Name the two scientists discovered the effect of it.
- What are mycoplasmas? Name two diseases caused by mycoplasmas.
5.Difference between the following pair with example: 2 1/2 x 4 = 10
- Manure and fertiliser
- Drycell and storage cell
- Conductors and insulators
- Gram positive and Gram negative bacteria.
6.Define following with diagram (any four) 2 1/2 x 4 = 10
- Magnetic compass
- Electric circuit
7. Answer any two of following questions: 5 x 2= 10
- 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?
- What are the various types of bacteria? Give shape and one example of each.
- 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:
- Name two high yielding breeds/varities of the following: 1 x 5 = 5
(a) Cow (b) Buffalo (c) Hen (d) Wheat (e) Paddy.
- Write the full form of the following: 1 x 5 = 5
(a) KVIC (b) DDT (c) BHC (d) TMV (e) RNA.
- Name the types of chemical reaction: 1 x 5 = 5
- Name the disease causing microorganism: 1 x 5 = 5
(a) Food poisoning (b) AIDS (c) Measles
(d) Sleeping sickness (e) Ring worm.
- 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.
- Draw anyone labelled diagram: (a) Fractionating Tower (b) Dry cell