Basic Science Practice Question and Answer
8 Q: The maximum limit in decibels of sound intensity above which a person cannot hear—
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5f61c9fcd7fb716774bc0fab- 150 dbfalse
- 270 dbfalse
- 385 dbfalse
- 4120 dBtrue
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Answer : 4. "120 dB"
Explanation :
For short durations of time, sounds up to a 120 dB are bearable and also considered safe by the world health organization, but again, listening to sounds at such high frequencies at regular intervals of stretched time durations is totally unsafe and makes the ears vulnerable to permanent hearing loss.
Q: All green plants and certain blue-green algae which can produce food by photosynthesis are called the_____.
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5f5722f1c1a5d57a18306c50- 1Consumersfalse
- 2Autotrophtrue
- 3Decomposersfalse
- 4Bacteriafalse
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Answer : 2. "Autotroph"
Explanation :
An autotroph is an organism that can produce its own food using light, water, carbon dioxide, or other chemicals. Because autotrophs produce their own food, they are sometimes called producers. Most autotrophs use a process called photosynthesis to make their food.
Q: Why it is not advisable to sleep under a tree at night?
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5ef432e8d40ebf3f78335a80- 1Release of less oxygenfalse
- 2Release of more oxygenfalse
- 3Release of carbon dioxidetrue
- 4Release of carbon monoxidefalse
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Answer : 3. "Release of carbon dioxide"
Explanation :
Sleeping under a tree is not advisable at night, since photosynthesis does not occur, oxygen is not being produced by the trees. In addition to this, the trees continue respiring thereby causing the amount of carbon dioxide to be increased and the amount of oxygen to be reduced.
Q: Which one of the following organisms has a role in converting nitrates to free nitrogen?
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5ef585b0f2ebd073795f236b- 1Pseudomonasfalse
- 2Nitrosomonasfalse
- 3Nitrobacterfalse
- 4Rhizobiumtrue
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Answer : 4. "Rhizobium"
Explanation :
Nitrates are reduced back into nitrogen in the soil by a process called denitrification. This process is performed by bacteria like Pseudomonas denitrificans, etc.
Q: World Environmental Day is celebrated every year on:
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5ee9990b109b5d6e0162399c- 15 Mayfalse
- 25 Junetrue
- 35 Julyfalse
- 418 Julyfalse
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Answer : 2. "5 June"
Explanation :
World Environment Day is celebrated on June 5 every year to remind people to save nature and the earth by stopping their non-environmentally friendly activities. Let's know more about this day, its history, significance, and theme.
Q: Which of the following acids is used in car batteries?
1112 05ee99605109b5d6e01623341
5ee99605109b5d6e01623341- 1Nitric acidfalse
- 2Hydrochloric acidfalse
- 3Sulphuric acidtrue
- 4Hydrofloric acidfalse
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Answer : 3. "Sulphuric acid"
Explanation :
sulphuric acid is used in car batteries.
Q: Which of the following has a very strong aroma of the fruit?
6117 05ef97200d7fe817321a63486
5ef97200d7fe817321a63486- 1Ethyl acetatetrue
- 2Methanolfalse
- 3Methyl chloridefalse
- 4Methanoic acidfalse
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Answer : 1. "Ethyl acetate"
Explanation :
This colorless liquid has a characteristic sweet smell (similar to pear drops) and is used in glues, nail polish removers, and in the decaffeination process of tea and coffee. Ethyl acetate is the ester of ethanol and acetic acid; it is manufactured on a large scale for use as a solvent.
Q: Which of the following nutrients do NOT provide energy for animals?
1057 05ee8894a79b5ea388bed44fc
5ee8894a79b5ea388bed44fc- 1Fatsfalse
- 2Carbohydratesfalse
- 3Vitaminstrue
- 4Proteinsfalse
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Answer : 3. "Vitamins "
Explanation :
Vitamins do not provide energy as they are not stored in our bodies.