CBSE Class 7 Science NSO Olympiad MCQs with Answers Set H

LOGICAL REASONING

Question. Select a figure from the options which will continue the same series as established by the Problem Figures

Answer : A

Question. Arrange the given words in a meaningful sequence and select the correct option.
1. Probation 2. Interview
3. Advertisement 4. Selection
5. Application
A. 3, 5, 2, 1, 4
B. 3, 5, 2, 4, 1
C. 3, 5, 4, 2, 1
D. 3, 2, 5, 4, 1
Answer : B

Question. Count the number of triangles in the given figure.

A. 36
B. 38
C. 34
D. None of these
Answer : C

Question. If P is brother of Q, Q is sister of S and S is father of R, then how is R related to P?
A. Brother
B. Nephew
C. Son
D. Cannot be determined
Answer : D

Question. Select the correct water image of Fig. (X).

Answer : A

Question. Find the missing number, if a certain rule is followed either row-wise or column-wise.

A. 173
B. 153
C. 182
D. 142
Answer : B

Question. Group the given figures into three classes on the basis of their identical properties using each figure only once.

A. 1, 6, 9; 3, 4, 7; 2, 5, 8
B. 3, 1, 6; 4, 5, 7; 2, 8, 9
C. 1, 6, 9; 3, 5, 8; 2, 4, 7
D. 1, 4, 9; 3, 5, 7; 2, 6, 8

Answer : C

Question. Riya walks 15 m towards West. She turned left and walks 20 m. She then turned left and walked 15 m.
After this she turned to her right and walks 12 m.
How far and in which direction is she now from the starting point?
A. 32 m, South
B. 47 m, East
C. 42 m, North
D. 42 m, South
Answer : A

Question. The given question consists of a set of three figures X, Y and Z showing a sequence of folding of a piece of paper. Fig. (Z) shows the manner in which the folded paper has been cut. Select a figure from the options which would most closely resemble the unfolded form of Fig. (Z).

Answer : A

Question. If the first and third digits in each of the following numbers are interchanged and then the numbers are arranged in descending order. What will be the middle digit of the middle number?
613 432 573 485 907
A. 8
B. 1
C. 3
D. 7
Answer : D

SCIENCE

Question. The given diagram shows five bulbs connected to two dry cells. When one of the bulbs is faulty, the other four bulbs remain lighted. Which bulb is faulty?

A. 1 only
B. 3 only
C. 2 or 4 only
D. 2 or 4 or 5 only
Answer : D

Question. Which of the following statements are correct?
(i) Increased wind speed results in reduced air pressure.
(ii) Wind current occurs due to the uneven heating of the earth by the sun.
(iii) In thunderstorm it is safe to lie on the ground.
(iv) High pressure prevailing at the centre of the cyclone is called the eye.
A. (i) and (ii) only
B. (ii) and (iii) only
C. (i) and (iv) only
D. (ii), (iii) and (iv) only
Answer : A

Question. Which of the following statements are correct about pots?
(i) Black pots are used for cooking because they increase the rate of cooking.
(ii) Silver pots are used for keeping food warm because they decrease the rate of heat dissipation.
(iii) Pots are made of clay to increase the rate of cooking.
A. (i) and (ii) only
B. (i) and (iii) only
C. (ii) and (iii) only
D. (i), (ii) and (iii)
Answer : A

Question. Anu shone a torchlight at a bunch of grapes as shown here. What can Anu do to enlarge the shadow of the bunch of grapes on the screen?

(i) Shift the grapes nearer to the torchlight.
(ii) Shift the screen away from the grapes.
(iii) Shift the screen closer to the grapes.
(iv) Shift the torchlight further away from the grapes.
A. (i) and (iii) only
B. (i) and (ii) only
C. (iii) and (iv) only
D. (ii) and (iv) only
Answer : B

Question. Raju used a magnet to attract an iron nail. Then he observed that more nails could be attracted in a manner as shown here. N represents north pole of magnet.
Which of the following statements about the iron nails is correct?

A. P and S are the north poles.
B. Q will repel T.
C. S and U will attract each other.
D. R and T are like poles.
Answer : D

Question. Figure shows a ray of light P striking a mirror AB.
The mirror AB and the mirror CD makes an angle of 120° with each other.

What is the angle of reflection at mirror CD?
A. 50°
B. 40°
C. 30°
D. 90°
Answer : A

Question. A current-carrying wire is coiled around an iron horseshoe as shown in the figure. What are the polarities at X and Y?

          At X               At Y
A. North pole       North pole
B. South pole      South pole
C. North pole      South pole
D. South pole      North pole
Answer : B

Question. A train leaves a station X at 5:00 pm and reaches another station Y at midnight. Its speed is 90 km h^–1.
What is the distance between stations X and Y?
A. 480 km
B. 630 km
C. 800 km
D. 830 km
Answer : B

Question. Read the given statements and select the correct option.
Statement 1 : If you hold a paper strip of 20 cm width between the forefinger and thumb and blow air over its top, then the far end of the paper strip begins to lift upwards.
Statement 2 : Pressure reduces when air moves with high speed.
A. Both statement 1 and statement 2 are true and statement 2 is the correct explanation of statement 1.
B. Both statement 1 and statement 2 are true but statement 2 is not the correct explanation of statement 1.
C. Statement 1 is true but statement 2 is false.
D. Statement 1 is false but statement 2 is true.
Answer : A

Question. A ray of light travels from air to water as shown in figure. What are ray AB and ray AC?

         Ray AB                    Ray AC
A. Reflected ray           Refracted ray
B. Reflected ray           Reflected ray
C. Refracted ray          Reflected ray
D. Refracted ray          Refracted ray
Answer : A

Question. Shruti tested the nature of a few common substances with the help of some indicators. Indicators used and changes she observed are as follows

Substances present in test tubes I, II, III and IV are respectively
A. Salt solution, curd, lemon juice and vinegar
B. Orange juice, window cleaner, sugar solution and lime water
C. Vinegar, soda water, soap solution and lemon juice
D. Lemon juice, lime water, window cleaner and soap solution.
Answer : B

Question. Match column I with column II and select the correct option from the given codes.

A. P - (i), Q - (ii), R - (iv), S - (iii)
B. P - (iv), Q - (iii), R - (ii), S - (i)
C. P - (ii), Q - (iv), R - (i), S - (iii)
D. P - (iii), Q - (i), R - (ii), S - (iv)
Answer : D

Question. Observe the given change carefully and identify W, X, Y and Z.

Answer : D

Question. Consider the following pairs of substances :
I : Glass plate and steel plate
II : Iron nail and wooden rod
III : Glass marble and flower petals
IV : Chalk powder and sugar
Which of the following represents the properties best suitable to distinguish between the substances of each pair?

Answer : B

Question. Ms Rakhi, a science teacher listed some keywords on the blackboard as :
(i) Freezing (ii) Evaporation (iii) Melting
(iv) Sublimation (v) Condensation (vi) Vaporisation
She asked students to match the keywords with the common changes which are listed as :
P : When we put a lid on a vessel containing hot milk, the inside of the lid gets wet.
Q : When we breathe onto a cold mirror it turns foggy.
R : When we spread hard butter on a warm toast, it becomes soft.
S : Solid piece of an air freshener kept on the bathroom shelf disappears in a few days.
T : When we put ice cubes in water, they disappear after some time.
U : Milk left in the freezer becomes ice cream.
The correct match is
A. P - (ii); Q - (vi); R, S - (iii); T, U - (i)
B. P, Q - (ii); R - (iii); S - (iv); T, U - (i)
C. P, Q - (v); R, T - (iii); S - (iv); U - (i)
D. P - (i); Q, R - (v) ; S, T - (iii); U - (iv)
Answer : C

Question. Observe the given figure carefully and choose the incorrect statement(s).

I. Large volume of acid should be added to a small volume of water slowly.
II. The figure represents the process of concentrating dilute H₂SO₄.
III. The process involves release of a large amount of heat.
IV. Water should not be stirred.
A. I and IV only
B. II and III only
C. I, II and IV only
D. II only
Answer : C

Question. Ria, a class 7 student classified a few changes as shown in the table :

The changes classified correctly are
A. I, IV and V only
B. I, II and IV only
C. I and V only
D. I, II, III, IV and V
Answer : A

Question. Study the given Venn diagram and identify points 1, 2 and 3.

Answer : C

Question. Radhika classified plants into three groups of three members each. By mistake, she placed one incorrect member in each group. Identify this odd member and select the correct option.
Group I : Nepenthes, Rafflesia, Drosera
Group II : Cuscuta, Hydnora, Utricularia
Group III : Hibiscus, Petunia, Dionaea
A. Drosera in group I should be interchanged with Hydnora in group II.
B. Utricularia in group II should be interchanged with Petunia in group III.
C. Rafflesia in group I should be interchanged with Hibiscus in group III.
D. Utricularia in group II should be interchanged with Rafflesia in group I whereas Dionaea in group III should be replaced with Ocimum.
Answer : D

Question. The given graph shows how the rate of breathing of a person changes under different conditions. At the beginning of each experiment, the person is breathing in atmospheric air.

What conclusion may be derived from the graph?
A. High level of oxygen in the air causes breathing rate to drop, regardless of carbon dioxide level.
B. Increase in carbon dioxide level in air causes breathing rate to increase upto a limit.
C. Breathing rate is controlled only by oxygen content of air and is independent of carbon dioxide concentration.
D. None of these
Answer : B

Question. Refer to the given Venn diagram and select the correct option regarding X and Y.

         X                     Y
A. Aloe                   Mint
B. Coriander          Maize
C. Basil                  Mustard
D. Palm                  Bamboo
Answer : B

Question. Refer to the given figure showing different temperature zones of the Earth and select the correct statement.

A. Labelled parts P and U are the torrid zones.
B. Labelled parts Q and T are temperate zones.
C. Labelled parts R and S are frigid zones.
D. None of these
Answer : B

Question. Refer to the given dichotomous key and select the correct option regarding P, Q, R and S.
I. (a) It is a vitamin deficiency disease. – Go to II
(b) It is a mineral deficiency disease. – Go to III 
II. (a) It is characterised by bleeding gums and aching joints. – P
(b) It is characterised by red rashes, scaly lesions on skin, diarrhoea, dementia, etc. – Q
III. (a) It affects haemoglobin formation in blood. – R
(b) It affects many metabolic processes of the body and is often characterised by prominent swelling in neck region. – S
A. P is caused by vitamin C deficiency whereas Q is caused by vitamin E deficiency.
B. P is scurvy, Q is pellagra, R is anaemia and S is goitre.
C. Person suffering from R should take iodised salt and more of citrus fruits.
D. Diseases P and Q occur in children only whereas diseases R and S occur only in adults.
Answer : B

Question. Refer to the given pie  diagram representing composition of soil. 

Select the correct option regarding constituents X and Y.
A. X is formed by weathering of parent rock.
B. Y contains nutrients required by the plants for their proper growth.
C. X is composed of gravel, sand, silt or clay.
D. All of these
Answer : D

Question. Small population of three organisms P, Q and R were reared in captivity for sometime. The given graph shows changes in their populations over time.

Study the graph and select the correct statements regarding organisms P, Q and R.
(i) Q could be a heterotroph whereas P and R could be autotrophs.
(ii) Q is a herbivore that feeds exclusively on P.
(iii) If population of R is removed from this community, then population of P will decrease whereas that of Q will increase.
(iv) P is a carnivore, Q is a herbivore whereas R is an omnivore that feeds on both P and Q.
(v) R is the predator of P which in turn is the predator of Q.
A. (ii) and (v) only
B. (i), (iii) and (iv) only
C. (i) and (ii) only
D. (iii), (iv) and (v) only
Answer : C

Question. The given figure shows the cross sections of two blood vessels X and Y found in humans.

Identify them and select the incorrect option regarding them.
A. X always carries oxygen rich blood away from the heart whereas Y always carries carbon dioxide rich blood towards the heart.
B. Y is provided with valves to prevent the back flow of blood whereas valves are absent in X.
C. X is usually deep seated whereas Y is superficially placed.
D. Pressure of blood is much higher in X as compared to Y.
Answer : A

Question. Refer to the given flow chart and select the incorrect option regarding P, Q, R and S.

A. P may have mammary glands and may respire through lungs whereas Q may have jointed appendages and may respire through tracheae.
B. Q could be a fish with 2 chambered heart or a reptile with 3 chambered heart.
C. R may have unsegmented body with distinct head, muscular foot and visceral hump.
D. S could be a detritivore which respires through its moist skin and is often called as farmer's friend.
Answer : B

Question. The given graph shows rate of water movement through trunk and branches of a tree during a day.

Which of the following can be inferred from the graph?
A. More water passes through the trunk than the branches.
B. The greatest increase in the rate of water movement first occurs in branches.
C. The increase in the rate of water movement first begins in the trunk.
D. None of these
Answer : B

Question. Which of the following is not an adaptation?
A. Some aquatic animals possess gills for breathing and have streamlined bodies.
B. Forelimbs of birds are modified into wings and they have hollow air filled bones.
C. People living in plains suffer from altitude sickness when they visit mountainous regions but soon recover and adjust to the changes.
D. Animals inhabiting polar regions have thick furs and thick layers of subcutaneous fat.
Answer : C

Question. Mr Khanna had a pond in his garden, filled with all kinds of aquatic plants. He wanted to prevent mosquitoes from breeding in the pond without harming the plants in any way. He could __________.
(i) Add salt into the water
(ii) Add some goldfish into the pond
(iii) Spray a film of oil on the surface of the pond
A. (i) only
B. (ii) only
C. (iii) only
D. (i), (ii) and (iii)
Answer : B

Question. The given graph shows changes in pH of water in an undisturbed freshwater lake on a summer day. What is the probable cause of the rise in pH of water between time period X and Y?

A. Decreased level of mineral nutrients in water.
B. Decreased level of carbon dioxide in water due to photosynthesis performed by water plants.
C. Increased level of carbon dioxide in water due to respiration performed by water plants and animals.
D. None of these
Answer : B

Question. Refer to the given pie chart representing the composition of air.

Which of the following is the incorrect statement regarding it?
A. X is an important component of fertilisers and proteins present in our body.
B. Y is necessary for humans to get energy from food.
C. During the process of burning X is used up and Z is given out.
D. Both B and C
Answer : C

Question. Refer to the given diagram of human digestive system and select the correct option regarding its labelled parts P, Q, R, S and T.

A. R secretes digestive enzymes viz. amylase, lipase, pepsin, trypsin, etc.
B. P secretes bile juice whereas T secretes hydrochloric acid.
C. S is longer in herbivores as compared to carnivores to aid the digestion of cellulose rich food.
D. Q is the largest digestive gland which secretes different enzymes for digestion of fats, proteins and carbohydrates.
Answer : C

Question. Complete the given paragraph by selecting the correct option.
Jute is a rainy season crop and grows best in (i) climate. It grows well in (ii) soil receiving silt from annual floods, as in the Sunderban delta in (iii) and (iv) .
A. (i)-Warm and humid, (ii)-Alluvial, (iii)-India, (iv)-Bangladesh
B. (i)-Cold and dry, (ii)-Black, (iii)-India, (iv)-Bangladesh
C. (i)-Warm and humid, (ii)-Sandy, (iii)-India, (iv)-Nepal
D. (i)-Cold and dry, (ii)-Alluvial, (iii)-Bangladesh, (iv)-Nepal
Answer : A

Question. Read the following statements and select the incorrect one.
A. Platelets are smaller in size than both RBCs and WBCs.
B. Platelet count decreases during certain infections.
C. Platelets prevent blood loss in case of any injury.
D. None of these
Answer : D

ACHIEVERS SECTION

Question. Which of the following cannot be speed-time (v – t) graph(s)?

A. (ii) and (iv) only
B. (iii) and (v) only
C. (iv) only
D. (i) only
Answer : D

Question. Fill in the blanks in the given table by choosing an appropriate option.

Answer : C

Question. Refer to the given paragraph where few words have been italicised.
Wool is obtained from fleece of certain animals. Angora wool is obtained from Angora goat. It is much warmer and softer than other wools. Mohair wool is obtained from Angora rabbit. Cashmere is obtained from yak and is common in Kashmir. Llama, Alpaca and Vicuna are members of camel family that yield extremely fine and expensive wool.
Select the correct option regarding this.
A. Softer should be replaced with harder whereas Vicuna should be replaced with Lohi.
B. The positions of goat and rabbit should be interchanged.
C. Yak should not be replaced as it is correctly mentioned whereas Kashmir should be replaced with Kota.
D. Camel should be replaced with sheep whereas Llama should not be replaced as it is correctly mentioned.
Answer : B

Question. Refer to the given dichotomous key and select the correct option regarding P, Q, R and S.
I. (a) Plant shows natural vegetative propagation. – Go to II
(b) Plant reproduces through asexual spores. – Go to III
II. (a) Plant propagates through stem. – P 
(b) Plant propagates through leaves. – Q
III. (a) Leaves of plants called fronds contain spores. – R
(b) Short plants that grow only in moist habitats and bear spores in spore case or capsule. – S
A. P could be Chrysanthemum or strawberry whereas R could be mushroom or mould.
B. Q could be Bryophyllum or Begonia whereas S could be fern or moss.
C. P and Q may produce flowers and seeds whereas both these structures are absent in R and S.
D. P could be garlic that propagates through bulbs or turmeric that propagates through tuber whereas Q could be Petunia or Begonia.
Answer : C

Question. Refer to the given food web operating in a community. Large amount of insecticides was sprayed in this community.

Which of the following graphs correctly depicts the changes in numbers of mice, caterpillars and sparrowhawks over time?

Answer : D