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An animal X enters inside another animal Y. Animal X gets food from the animal Y. Animal Y’s health over time is represented in the given graph. P is the time when the two animals came in contact. What is the mode of nutrition of animal X ?


AAutotrophic
BHeterotrophic
CParasitic
DSaprotrophic

What will happen if you keep a solution of copper sulphate in an iron container for a few days? What is the reason for your observation?

A The surface of iron container will develop a green layer due to corrosion caused by copper sulphate.
B Copper metal will be deposited in iron container since copper is more reactive than iron.
C Nothing will happen since no reaction takes place between copper sulphate and iron.
D Holes will be formed in the container since iron is more reactive than copper hence iron displaces copper from a solution of copper sulphate.

Which of the following is NOT hidden in the given word grid?


A A material formed by twisting of fibres and is used to make fabric.
B A natural and a synthetic fibre.
C A temporary house used by campers, nomads and soldiers
D A temporary house which can move through a lake.

Refer to the given Venn diagram.

Which of the following can be placed at X ?
(i) Manufacture of different antibiotics
(ii) Preparing yogurt
(iii) Fermentation of sugar to get alcohol
(iv) Manufacture of vitamin B complex tablets
(v) Decomposition of organic waste and ensuring nutrient recycling in ecosystem
(vi) Causing diseases in plants and animals

A (ii), (iii) and (vi)
B (i), (ii), (v) and (vi)
C (i), (iii), (iv), (v) and (vi)
D (ii), (iii), (iv) and (v)

Transpiration has been described as a 'necessary evil' because it is inevitable, but potentially harmful. Which of the following statements describe this?
(i) It causes absorption of mineral salts.
(ii) It regulates plant temperature.
(iii) It causes wilting and injury in plants.
(iv) It causes ascent of sap.

A (i) and (iv) only
B (i), (ii) and (iii) only
C (i), (ii) and (iv) only
D (i), (ii), (iii) and (iv)

Study the above given food web. Which of the following graphs shows how populations of S, T and U are likely to be affected if there is a mass migration of V out of the habitat?

A

B

C

D

A car travelling normally towards a cliff at a speed of 50 m s^–1, sounds its horn when it is 0.7 km away. Taking the speed of sound to be 300 m s^–1 in air, find the time taken for the driver to hear its echo.

A 0.04 s
B 4.0 s
C 4.7 s
D 28.0 s

Unscramble the given options and select the option that gives the term used for the process of separating cotton fibres from seeds.

A EVNGWAI
B NIGGINN
C SNGIERAH
D NTINKITG

The given diagram represents a village. The waste material from residential area and factories is dumped into the river stream that passes through the village. Which line in the graph correctly shows the change in the population of aquatic fish when they swim downstream from points P to Q?


A I
B II
C III
D IV

Raj is son of Rani and father of Sahil. If Meena is the mother of Sahil, then how is Meena related to Rani?

ADaughter
BMother
CDaughter-in-law
DSister