Question

can someone solve this question please?
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Answer 1

★ Required Answers ★

Give reasons for the following questions:

i) Why is the soil suitably levelled before sowing seeds?

$\longrightarrow$ The soil is suitably levelled before sowing seeds because of many ways :–

• As soil will be levelled so that there will be equal distribution of manure and fertilizers.
• Levelling of the soil also helps in preventing the loss of moisture from the soil.
• Because of levelling soil is settled and it is not eroded by wind or water.

ii) Why are borad-pins made sharp?

$\longrightarrow$ This is because if it is made sharp then it can penetrate into the board easily as there will be less area and more pressure.But if it is made blunt then it can't penetrate into the board easily when we'll apply the force. Thus, borad-pins are made sharp.

iii) Why cell wall is present only in plant cells not in animal cells?

$\longrightarrow$ Animal cells can move but since the plants cells can't move,so they need protection against variations in temperatures,humidity and so on. That's why cell wall is present only in plant cells not in animal cells.

iv) Why is it dangerous to touch electric appliances with wet hand?

$\longrightarrow$ Since water is the good conductor of electricity so when we'll touch electric appliances with wet hand ,water present on our hand will allow electric current to pass through it and we may get shock. So, it is dangerous to touch electric appliances with wet hand.

v) Why rayon is called semi-synthetic fibre?

$\longrightarrow$ This is because rayon is prepared from a naturally occurring polymer cellulose which comes from the wood pulp.Although it is obtained from a natural source yet rayon is man-made fibre as the original raw material(cellulose) is broken down and then reformed chemically.So,it is partially synthetic fibre or we can say that it is semi-synthetic fibre.

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