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Subject :NSO    Class : Class 7

Digestive juices were collected from three different regions of the alimentary canal. Drops of these juices were added to wells made in an agar of starch as shown in the given figure.

After an hour, the wells were rinsed with distilled water and flooded with iodine solution. The results are given in the table.

Well 1 2 3
Colour of iodine
solution
Blue-black Yellow - brown Yellow - brown
Which of the following correctly identifies the regions of the alimentary canal from which the three digestive juices were obtained?

AWell 1 represents region that contains an enzyme pepsin that causes the breakdown of proteins into simple substances.
BWell 2 could represent region that contains an enzyme called salivary amylase.
CWell 3 could represent region that is the longest portion of alimentary canal and receives bile juice from liver and pancreatic juice from pancreas.
DAll of these


The options are placed wrongly. Well 1 cannot turn blue-black as it has protein. Well 2 should turn blue-black because it has starches. Only option c is correct. The answer is C

Ans 1:

Class : Class 8
I guess the answer is option D.. You see that if well 2 has salivary amylase, then the starch will be converted into simple sugars => No starch is found from that well (it has converted to simpler form)

Ans 2:

Class : Class 7

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Subject :NSO    Class : Class 7

Ans 1:

Class : Class 8
Option c is right..

Ans 2:

Class : Class 8
please specify reason

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Subject :NSO    Class : Class 3

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Subject :NSO    Class : Class 5

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Subject :NSO    Class : Class 7

The given diagram shows an experimental set-up to study osmosis. Which of the following combinations of liquids would cause liquid X to rise to the highest level in the glass tube after three hours?


  Liquid X Liquid Y
A Concentrated
sucrose solution
Dilute sucrose
solution
B Concentrated
sucrose solution
Water
C Dilute sucrose
solution
Concentrated sucrose
solution
D Water Concentrated sucrose
solution


Ans 1:

Class : Class 8
The answer must be b.. Isn't it?!!

Ans 2:

Class : Class 8

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Subject :NSO    Class : Class 5

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Subject :NSO    Class : Class 10

Ans 1:

Class : Class 10
THE ANSWER FOR THIS QUESTION IS C.BECAUSE WHEN THE RATIO IS 3:2:1 THEN THE FIRST HYDROCARBON MUST BE A AN ALKANE .THUS OPTION ONE IS WRONG.THE SECOND OPTION WILL ALSO BE INCORRECT BECAUSE BROMIN WATER IS APPLICABLE TO UNSATURATED CARBON COMPOUNDS ,AND 2 AND 3 ARE UNSATURATED CARBON COMPOUNDS,SO OPTION TWO IS ALSO WRONG.FINALLUY THE OPTION THREE IS CORRECT AS TOLLENS TEST IS APPLICABLE TO CARBON COMPOUNDS WIT ALDEHYDE GROUP AND 2 AND 3 DOES NOT CONTAIN ALDEHYDE GROUP

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Subject :NSO    Class : Class 6

Ans 1: (Master Answer)

Class : Class 1

D

In the given circuit , the bulb will glow when the circuit will complete.For this to happen switch S3 must be closed .Along with this either or both of switch S1 and S2  should be closed.


Ans 2:

Class : Class 3

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Subject :NSO    Class : Class 3

Ans 1:

Class : Class 3
d

Ans 2:

Class : Class 3

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Subject :NSO    Class : Class 6

When Asha suspended four bars of different materials from a pole and brought the North pole of a bar magnet near part P and Q of each bar one by one as shown in figure, then observations she recorded are as follows:

Which of the following sets correctly represents metal bars I, II, III and IV?

Bar I Bar II Bar III Bar IV
A Magnet Stainless steel Bar Magnet Iron bar
B Magnet Iron bar Magnet Glass bar
C Stainless steel bar Magnet Iron bar Magnet
D Magnet Iron bar Glass bar Stainless steel bar


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