KENDRIYA VIDYALAYA STEEL PLANT - CLASS VII SCIENCE SAMPLE PAPER (SET 2)
1. Features that distinguish males from females but are not directly involved in reproduction are called:
(a) Primary sexual characteristics
(b) Secondary sexual characteristics
(c) Puberty traits
(d) Hormonal markers
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Answer: (b) Secondary sexual characteristics
2. The menstrual cycle in healthy girls generally recurs every:
(a) 10–15 days
(b) 21–35 days
(c) 28–30 days
(d) 45–55 days
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Answer: (c) 28–30 days
3. Houses in hot regions use hollow bricks because the trapped air acts as a/an:
(a) Good conductor of heat
(b) Poor conductor of heat
(c) Radiator of heat
(d) Absorber of heat
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Answer: (b) Poor conductor of heat
4. In ancient India, a standard unit of time measured by a sinking bowl water clock was:
(a) Second
(b) Ghatika
(c) Yantra
(d) Shadow unit
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Answer: (b) Ghatika
5. Which instrument measures the distance travelled by a vehicle in kilometres?
(a) Speedometer
(b) Odometer
(c) Thermometer
(d) Stopwatch
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Answer: (b) Odometer
6. Saliva contains digestive juices that help break down starch into:
(a) Proteins
(b) Fats
(c) Sugar
(d) Acid
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Answer: (c) Sugar
7. Birds break down food in a chamber called the:
(a) Rumen
(b) Stomach
(c) Gizzard
(d) Alveoli
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Answer: (c) Gizzard
8. In a model showing the mechanism of breathing, balloons represent the:
(a) Windpipe
(b) Chest cavity
(c) Lungs
(d) Diaphragm
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Answer: (c) Lungs
9. Average speed is defined as:
(a) Total distance / Total time
(b) Total distance + Total time
(c) Total time / Total distance
(d) Speed at a specific moment
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Answer: (a) Total distance / Total time
10. Deficiency of which nutrient in adolescents, especially girls, can lead to blood-related health problems?
(a) Calcium
(b) Vitamin C
(c) Iron
(d) Carbohydrates
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Answer: (c) Iron
11. Case: Vitamin B12 and Science
Dorothy Hodgkin was a brilliant scientist who studied the structure of Vitamin B12 and won the Nobel Prize in Chemistry in 1964. Vitamin B12 is essential for proper body functioning but cannot be made by the human body; it must be obtained from food.
Questions:
(i) Name the scientist who won a Nobel Prize for studying Vitamin B12. (1M)
(ii) Can the human body produce Vitamin B12? (1M)
(iii) Why is iron important for adolescent girls? (2M)
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(i) Dorothy Hodgkin. (ii) No, it must be obtained from food. (iii) Iron is crucial for the formation of blood and preventing deficiencies that lead to health problems.
12. Case: The Stone Sundial
The world’s largest stone sundial, the Samrat Yantra, is located at Jantar Mantar in Jaipur. It is 27 metres tall, and its shadow moves at 1 millimetre per second, allowing measurement of time intervals as short as 2 seconds.
Questions:
(i) Where is the Samrat Yantra located? (1M)
(ii) How short an interval can this sundial measure? (1M)
(iii) How does a sundial determine the time of day? (2M)
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(i) Jantar Mantar, Jaipur, Rajasthan. (ii) 2 seconds. (iii) Time is determined by the changing position of the shadow of an object cast by the light of the Sun during the day.
13. Match Column A with Column B:
(i) Stomach (a) Inverted paper cup rising
(ii) Hot Air (b) Churning of food
(iii) Earthworm (c) Time based on sand flow
(iv) Hourglass (d) Breathing through moist skin
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(i)-(b), (ii)-(a), (iii)-(d), (iv)-(c)
14. Explain how heat transfer occurs in solids.
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In solids, heat transfer takes place mainly through conduction. Particles receive heat and pass it to neighbours while staying in their fixed positions.
15. Distinguish between breathing and respiration.
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Breathing is a physical process of inhaling and exhaling air, while respiration is a chemical process that breaks down glucose using oxygen to release energy. Both are essential for survival.
16. What are ruminants and how do they digest food?
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Ruminants are grass-eating animals like cows that partially chew and swallow food. Later, this partially digested food returns to the mouth for thorough chewing.
17. Why is it recommended to breathe through the nose rather than the mouth?
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The tiny hair and mucus inside nostrils help trap dust and dirt from the air we breathe. This filters the air before it reaches the lungs.
18. Define the time period of a simple pendulum.
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The time period is the total time taken by the bob of a pendulum to complete one full oscillation. This period remains constant for a pendulum of a given length at a specific location.
19. Explain the continuous movement of water in the water cycle.
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Water cycle involves water evaporating from bodies and plants as vapour, then rising and condensing to form clouds. This water returns to Earth as precipitation like rain or snow. This continuous process redistributes water and replenishes sources like rivers and groundwater. It ensures the conservation of the total amount of water on Earth.
20. Discuss the common physical and emotional changes associated with adolescence.
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Physical changes include rapid height increase, weight gain, voice changes like the Adam’s apple in boys, and acne development. Both genders experience hair growth in specific body regions. Emotionally, adolescents face mood swings and stronger emotions than in childhood. These changes are natural signs of puberty controlled by hormones produced in the body.
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