What is menstruation? Explain.
At puberty, in girls the ovaries get enlarged and starts producing eggs (ovum). One egg matures and is released by one of the ovaries at a time or we can say once in about 28 to 30 days. During this period, the wall of the uterus become thick so as to receive the egg. If the egg is fertilized then it begins to develop and results in pregnancy and if this egg is not fertilized then the released egg and thickened lining of the uterus along with its blood vessels are shed off causing bleeding in female which is known as menstruation.
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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Explain why a charged body loses its charge if we touch it with our hand.
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Mark the following statements as true (T) or false (F):
(a) Pole Star is a member of the solar system. ( )
(b) Mercury is the smallest planet of the solar system. ( )
(c) Uranus is the farthest planet in the solar system. ( )
(d) INSAT is an artificial satellite. ( )
(e) There are nine planets in the solar system. ( )
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Suppose you are in a dark room. Can you see objects in the room? Can you see objects outside the room. Explain.
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Explain how CO2 is able to control fires.
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Explain how you can take care of your eyes.
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Make a sketch of the human nerve cell. What function do nerve cells perform?
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Which of the following cannot be charged easily by friction?
(a) A plastic scale
(b) A copper rod
(c) An inflated balloon
(d) A woollen cloth.
- NCERT Chapter