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7th (VII) Chapter: 07: Respiration of plants and Animals Hots Questions Solved

7th (VII) Chapter: 07: Respiration of plants and Animals Hots Questions Solved
1. Why do plants have respiratory system?

Ans: Plants directly absorb CO2 through stomata present in leaves and used to prepared food and release O2

2. Why do we yawn when we are sleepy?

Ans: when we are sleepy our brain needs more oxygen to function properly. We yawn to gather a large amount of oxygen for our brain, to help it function faster and control drowsiness.

3. Can respiration take place in absence of oxygen?

Ans: Yes, Respiration takes place in absence of oxygen when we are doing some strenuous activity. It is called anaerobic respiration.

4. What do you mean by Vital Capacity? What is vital capacity of a normal man?

Ans: The maximum volume of air inhaled or exhaled by lungs is called vital capacity. It is measured by Spirometer.The vital capacity of a normal man is 4 to 6 lit.

Chapter: 09: Reproduction in Plants and Animals

1. Can a single plants cell develop into entire plants?

Ans: No, single cell when grown up splits up into two daughter cells. This continues throughout life of plants.

2. Can insect pollinated flower be pollinated by wind?

Ans: No, it is because Insect pollinated flower have brightly coloured petal to attract insect that are not present in wind pollinated flower.

3. What are function of flower and fruits in plants?

Ans: Flowers help in reproduction give rise to fruit and seeds. 
The main function of a fruit is to protect seeds while they germinate and to help disperse seeds away from the parent plant.

4. What is Scion?

The young vegetative part of plants use in artificial method of reproduction like grafting is called scion.

5. Name the method of reproduction that involves only one parent is called?

Ans: The method of reproduction that involves only one parent is called asexual reproduction. For example, in amoeba, paramecium etc.

6. Which is the largest fruit in the world?

Ans: Jack fruit

7. What are sperms meant for?

Ans: Sperms carry the male gamete or the genetic material of the father which gets inherited to the offspring when male and female gamete fuse and form the zygote.

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