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Subject :NSO    Class : Class 4

Rohit performed an experiment wherein he set up three test tubes as shown in the figure. Select the INCORRECT statement regarding this.


ATest tube P will have most carbon dioxide after three hours.
BTest tube Q will have least oxygen after three hours.
COrganisms in test tube R will survive for a longer time as compared to organisms in test tubes P and Q.
DNo oxygen will remain in test tube P after some time.


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Ans 1:

Class : Class 4

Ans 2:

Class : Class 4

Ans 3:

Class : Class 5

Ans 4:

Class : Class 3

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Subject :NSO    Class : Class 4

Ans 1:

Class : Class 3

Ans 2: (Master Answer)

Class : Class 1
The correct answer is D.

Ans 3:

Class : Class 3
the correct answer is d

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Subject :NSO    Class : Class 6

Ans 1:

Class : Class 7

Ans 2:

Class : Class 7
the answer is d because the field lines of a magnet always travle from north to south

Ans 3:

Class : Class 8

Ans 4:

Class : Class 7

Ans 5:

Class : Class 7
understood?

Ans 6:

Class : Class 6

Ans 7:

Class : Class 7

Ans 8:

Class : Class 9
the field line travels from north to south

Ans 9:

Class : Class 7

Ans 10:

Class : Class 8

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Subject :NSO    Class : Class 7

Ans 1:

Class : Class 8

Ans 2:

Class : Class 8

Ans 3:

Class : Class 7
here option c holds true because in option a and b we can make an exception with pulmonary artery and vein.

Ans 4:

Class : Class 8

Ans 5:

Class : Class 8
Yes, the answer is option "C". It is not true that arteries will always carry oxygenated blood and the veins will always carry deoxygenated blood (pulmonary vein and artery).

Ans 6:

Class : Class 8
C

Ans 7:

Class : Class 8

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Subject :NSO    Class : Class 5

Ans 1:

Class : Class 5
you are correct Pragun goel . my answer is also a.

Ans 2:

Class : Class 7

Ans 3:

Class : Class 6
sea snakes also breathe through skin so option 1 should also be correct.

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Subject :NSO    Class : Class 3

Ans 1: (Master Answer)

Class : Class 1
The correct answer is C.

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Subject :NSO    Class : Class 7

Ans 1: (Master Answer)

Class : Class 1
Molars and Premolars are mainly used to chew the food.

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Subject :NSO    Class : Class 7

Ans 1:

Class : Class 7
The solution: Enzyme X works best and increases the rate of reaction at an acidic pH (less than 7) of about two2️⃣ ! Enzyme Y is very very very very very very very very very very very very very very very very very efficient @ slightly acidic pH i.e., slightly less than seven!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Enzyme Z is most efficient at an alkaline pH (more than 7!!!). And alkali means a base which is soluble in water. In humans, gastric juice of stomach (a J-shaped bag with thick inner walls. Meh.) has pH in the range of 1.5-2.5, where enzymes such as pepsin, rennin etc. carry out the digestion of food. Thus, enzyme X can be found in stomach. Similarly, the saliva in the mouth of humans has sliiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiightly acidic pH of 6.8, where salivary amylase enzyme is moooooooooooooooooooooooooooooooooooooooost effective! Thus, enzyme Y can be found in the buccal cavity. Small intestine has slightly alkaline pH of 7.8, where enzymes such as trypsin help in digestion of food. So, enzyme Z can be found in duodenum. Morus Alba is the scientific name of mulberry.

Ans 2:

Class : Class 7

Ans 3:

Class : Class 7
Is D. ✔

Ans 4:

Class : Class 7

Ans 5:

Class : Class 7
Can someone pls send the explanation of why it's D🙏

Ans 6:

Class : Class 3
such questions r always confusing.................

Ans 7:

Class : Class 7

Ans 8:

Class : Class 3

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Subject :NSO    Class : Class 4

Refer to the given paragraph and table and answer the following questions.
Neha took 100 gm each of three types of soil, X, Y and Z, in three separate pots with hole at the bottom. The amount of water that was poured in the soil pot, just before it started dripping from the bottom hole, is tabulated here.

The soil that is mixture of clay, sand, humus and is usually very good for growth of most plants is __________.

A X
B Y
C Z
D Cannot be determined


Ans shd be D (Cannot be determined)

Ans 1:

Class : Class 3

Ans 2:

Class : Class 5
B IS THE ANSWER ANURADHA NAIR 4C

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Subject :NSO    Class : Class 4

Ans 1:

Class : Class 4
Chloro-fluro-carbon

Ans 2:

Class : Class 5
I GOT IT CORRECT

Ans 3:

Class : Class 1
It should be CFCS

Ans 4:

Class : Class 5

Ans 5:

Class : Class 4
the ans should be CFC

Ans 6:

Class : Class 4
The answer is B as when we use electricity fuel gets burnt and so it produces carbon dioxide.

Ans 7:

Class : Class 3

Ans 8:

Class : Class 5
The answer was supposed to be CFC .

Ans 9:

Class : Class 5
Actually it is b ,as a is CNG(compressed natural gas which is a energy source that is not a greenhouse gas

Ans 10:

Class : Class 4
CFCS should be correct answer but I got it right

Ans 11:

Class : Class 4
THE OPTION SHOULD HAVE BEEN CFC OR WE CAN TAKE THE OPTION D [NITROGEN] BUT IT IS SHOWING WRONG

Ans 12:

Class : Class 3
the correct answer is CFCs .but is not mention in the option.

Ans 13:

Class : Class 5

Ans 14:

Class : Class 5
The correct answer should be CFC

Ans 15:

Class : Class 4
how the released gas from refrigerator is CO2

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