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In a village, farmers started using DDT as pesticide in their crop fields, located nearby river. Given table shows the concentration of DDT as found in tissues of various organisms present in that river.

Which of the following option shows the correct order in which these organisms are linked in a food chain?

AI → III → V → II → IV
BI → V → III → II → IV
CIV → II → III → V → I
DII → IV → V → III → I

Study the given table and fill in the blanks by selecting an appropriate option.

(i)-----(ii)-----(iii)-----(iv)

ASilver nitrate---Carbonic acid---Hydrochloric acid---Ammonium nitrate
BSodium nitrate---Hydrochloric acid---Carbonic acid---Silver nitrate
CPotashalum---Sulphuric acid---Nitric acid---Sodium nitrate
DAmmonium nitrate---Carbonic acid---Sulphuric acid---Silver nitrate

Mayank set-up an experiment as shown below.

Which of the following graphs correctly represents the changes in weights of Visking tubings P and Q?

A
B
C
D

Nutrient 'X' keeps teeth and bones healthy. It is present in orange and amla. Deficiency of 'X' results in bleeding gums.
Select the option that correctly identifies 'X'.

A Vitamin C
B Calcium
C Vitamin K
D Carbohydrate

There are four electromagnets as shown in the figure.

Which one of following options is correct regarding strength of electromagnets?

AI = II < III < IV
BI > II > III = IV
CI < II < III = IV
DNone of these

An electron jumps from an orbit P to Q and loses energy. The same electron when jumps from R to Q, gains energy.
The increasing order of distance of these orbits from the nucleus is

A P < Q < R
B R < P < Q
C R < Q < P
D P < R < Q

A brief information about two atoms X and Y is given:
X : Atomic number = 7, Mass number = 14
Y : Atomic number = 7, Mass number = 15
Which of the following is correct about these two atoms?

A Electronic configuration of X is 2, 8, 4 while that of Y is 2, 8, 5.
B Both X and Y contain 7 neutrons.
C X has 2 electron shells while Y has 3 electron shells.
D Both X and Y have 5 valence electrons.

‘R’ is the fifth planet from the Sun. Which of the following is correct regarding R?

A It is known as red planet.
B It has lowest number of Moons.
C It is the largest planet .
D It has a ring around itself.

Refer to the given dichotomous key and identify P, Q, R, S and T.
I. (A) Propagates vegetatively by natural methods. - Go to II
(B) Propagates vegetatively by artificial methods. - Go to IV
II. (A) New plant develops from stem of parent plant. - Go to III
(B) Roots of parent plant gives rise to new plant. - P
III. (A) Short underground stem covered with fleshy scale leaves. - Q
(B) Modified underground stems (bearing buds) which store food and become swollen. - R
IV. (A) Roots develop from young branch bent towards the ground and covered with soil. - S
(B) It involves placing of stem cutting of one plant over cut stem (having extensive roots) of other plant and tying them. - T

AP could be potato whereas R could be garlic.
BT could be coriander whereas S could be spinach.
CP could be beetroot whereas Q could be turnip.
DQ could be onion whereas S could be strawberry.

Refer to the given Venn diagram and select the correct option regarding P and Q.


AAngora, Mohair and cashmere are few varieties of P obtained from different mammals.
BP and Q when burnt give the smell of burning hair and charred meat respectively.
CFabric made of P can be used in winter clothing whereas fabric made of Q is waterproof hence can be used for making umbrellas or raincoats.
DReeling is involved in processing of P whereas fibre Q is obtained by retting.