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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Make a labelled diagram of a candle flame.
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Write notes on—
(a) Adam’s apple.
(b) Secondary sexual characters.
(c) Sex determination in the unborn baby. - Q:-
It is difficult to burn a heap of green leaves but dry leaves catch fire easily. Explain.
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What is a constellation? Name any two constellations.
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Complete the cross-word puzzle using the hints given below
Across
1. The process of the fusion of the gametes.
6. The type of fertilization in hen.
7. The term used for bulges observed on the sides of the body of Hydra.
8. Eggs are produced here.Down
2. Sperms are produced in these male reproductive organs.
3. Another term for the fertilized egg.
4. These animals lay eggs.
5. A type of fission in amoeba. - Q:-
Arrange the following boxes in proper order to make a flow chart of sugarcane crop production.
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Give two examples of each.
(a) Kharif crop
(b) Rabi crop - Q:-
Make a sketch of the human nerve cell. What function do nerve cells perform?
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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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Do all the stars in the sky move? Explain.
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