What are weeds? How can we control them?
Weeds are the undesirable plants or we can say unwanted plants that may grow naturally along with the crops. They are hazardous to the crops as they compete with the crops for the food, nutrients, water and sunlight. Hence, they must be controlled.
The process of controlling or removing the weeds (unwanted plants) from the field is known as weeding. There are several methods to remove weeds such as tilling in which weeds are uprooted. They are removed manually by cutting with the help of Khurpi. They are also controlled by chemicals known as weedicides which kills the weeds.
Popular Questions of Class 8 Science
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Describe with the help of a diagram an instrument which can be used to detect a charged body.
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Sketch larynx and explain its function in your own words.
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Arrange the following boxes in proper order to make a flow chart of sugarcane crop production.
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Make a labelled diagram of a candle flame.
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What is metamorphosis? Give examples.
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The following Table shows the total power shortage in India from 1991– 1997. Show the data in the form of a graph. Plot shortage percentage for the years on the Y-axis and the year on the X-axis.
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Make sketches of animal and plant cells. State three differences between them.
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What is a constellation? Name any two constellations.
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Describe the construction of a kaleidoscope.
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Complete the crossword with the help of clues given below:
Across
1. This is necessary for photosynthesis.
3. Term for component present in the cytoplasm.
6. The living substance in the cell.
8. Units of inheritance present on the chromosomes.Down
1. Green plastids.
2. Formed by collection of tissues.
4. It separates the contents of the cell from the surrounding medium.
5. Empty structure in the cytoplasm.
7. A group of cells.
Recently Viewed Questions of Class 8 Science
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List sources of noise pollution in your surroundings.
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An inflated balloon was pressed against a wall after it has been rubbed with a piece of synthetic cloth. It was found that the balloon sticks to the wall. What force might be responsible for the attraction between the balloon and the wall?
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Suppose your writing desk is tilted a little. A book kept on it starts sliding down. Show the direction of frictional force acting on it.
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Make a labelled diagram of a candle flame.
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The table below shows the data on likely heights of boys and girls as they grow in age. Draw graphs showing height and age for both boys and girls on the same graph paper. What conclusions can be drawn from these graphs?
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Prepare a list of objects around you that are electroplated.
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Explain the difference between the thermoplastic and thermosetting plastics.
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You spill a bucket of soapy water on a marble floor accidently. Would it make it easier or more difficult for you to walk on the floor? Why?
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What is metamorphosis? Give examples.
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Explain why fossil fuels are exhaustible natural resources.
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