Brain Grain · braingrain.in
Science — Practice Paper · Set 1
Class: 6Samacheer KalviMax Marks: 57
Name: ____________________Reg No: ____________
Part I — Multiple Choice Questions 10 × 1 = 10
Choose the correct answer. (Answer all questions.)
1.Oscillatory motion among the following isA. Rotation of the earth about its axisB. Revolution of the moon about the earthC. To and fro movement of a vibrating stringD. All of these[1]
2.A ‘control centre’ of the eukaryotic cell isA. Cell wallB. NucleusC. VacuolesD. Chloroplast[1]
3.Birds fly in the air with the help of _______A. heavy and strong BonesB. Soft and thick BonesC. Hollow and light BonesD. Flat and thick Bones[1]
4.The girth of a tree can be measured byA. Metre scaleB. Metre rodC. plastic rulerD. Measuring tape.[1]
5.Choose the correct oneA. km > mm > cm > mB. km> mm> m > cmC. km>m>cm>mmD. km > cm > m > mm[1]
6.All animals need _______A. Food and water onlyB. Water onlyC. Air, food and waterD. Food only[1]
7.What is the unit of length?A. metreB. litreC. secondD. kilogram.[1]
8.A newborn baby has ……….. bones.A. 206B. More than 200C. More than 300D. 210[1]
9.Plants are producers because they make their own food by _______A. RespirationB. ConsumerC. PhotosynthesisD. Decomposing[1]
10._______ change is a temporary changeA. PhysicalB. ChemicalC. UndesirableD. slow[1]
Part II — Fill in the Blanks 5 × 1 = 5
Fill in the blanks. (Answer all questions.)
11.Special features in plants which help them to survive in the habitats they live are known as ………. The Great Indian Desert is an arid region of rolling sandhills on the Indian sub continent is known as ………. ………. is the main vein of the lamina of the leaf. A change in an organism caused by environmental factors is known as ………[1]
12.Aquatic, deserts, mountains are called ………. Based on the number of cells present animals are classified into ………. and ……….. Tail of a bird acts as a rudder which helps to ……….. Amoeba moves with the help of …………[1]
13.Touch me not plant: ………… : : digestion of food : Irreversible change[1]
14.Primary consumers that eat plants are called ………. Temperature, light and wind are ………… factors. ………. is the process of converting waste materials into new materials. Water pollution can spread …………. and chemicals. The 3R’s are Reduce, ………….. and Recycle.[1]
15.Photosynthesis : ……….. change :: burning of coal : Human – made change[1]
Part III — True or False 3 × 1 = 3
Write True or False. (Answer all questions.)
16.Heat is a kind of energy that flows from a hot body to a cold body. Steam is formed when heat is released from water. Thermal expansion is always a nuisance. Borosilicate glass do not expand much on being heated. The unit of heat and temperature are the same.[1]
17.Air is not compressible. Liquids have no fixed volume but have fixed shape. Particles in solids are free to move. Then pulses are washed with water before cooking, the water is separated from them by the process of filtration. Strainer is a kind of sieve which is used to separate a liquid from solid Grain and husk can be separated by winnowing Air is a pure substance Butter from curds is separated by sedimentation.[1]
18.A cell is the smallest unit of life. Nerve cell is the longest cell Prokaryotes were the first form of life on earth. The organelles of both plants and animals are made up of cells. (Organelles – Found inside the cell) New cells are produced from existing cells.[1]
Part IV — Short Answer Questions 12 × 2 = 24
Answer briefly. (Answer all questions.)
19.Differentiate between the voluntary muscles and involuntary muscles.[2]
20.What are the two types of ecosystems?[2]
21.What are artificial magnets?[2]
22.Distinguish between properties of solid, liquid, gas. Draw a suitable diagram.[2]
23.A machine capable of carrying out a complex series of actions automatically.[2]
24.Give some examples of monocotyledonous plants and dicotyledonous plants.[2]
25.Why is called inorganic fertilizers?[2]
26.Trachea → Bronchi → Pharynx → Lungs → Larynx → Nasal cavity → Nostrils → Bronchiole → Alveolus[2]
27.What do you understand by thermal equilibrium?[2]
28.Write the uses of Neem?[2]
29.Tabulate the different components of an electric circuit and their respective symbols.[2]
30.What are the principal nutrients?[2]
Part V — Long Answer Questions 3 × 5 = 15
Answer in detail. (Answer all questions.)
31.You are provided with iron filings and a bar magnet without labelling the poles of the magnet. Using this ………. a. How will you identify the poles of the magnet?[5]
32.A habitat is a living or dwelling place of an organism. The geographical features and environmental conditions on earth remain the same from one place to another. Amoeba is a unicellular organism and moves with pseudopodia. Birds can see only one object at a time. Paramecium is a multicellular organism.[5]
33.How does electromagnetic train work?[5]
🔑 Show Answer Key — Set 1
- 1. (c) To and fro movement of a vibrating string
- 2. (b) Nucleus
- 3. (c) Hollow and light Bones
- 4. (d) Measuring tape.
- 5. (c) km > m > cm > mm
- 6. (c) Air, food and water
- 7. (a) metre
- 8. (c) More than 300
- 9. (c) Photosynthesis
- 10. (a) Physical
- 11. Adaptations Thar desert Midrib Modification
- 12. Habitat Unicellular, multicellular control the direction of the movement Pseudopodium.
- 13. Reversible change
- 14. herbivores physical Recycle diseases reuse
- 15. Natural
- 16. True. Heat is a kind of energy that flows from a hot body to a cold body. False. Steam is formed when heat is absorbed by water, not released from it. During the process of vaporization, water molecules gain energy and escape as steam. False. Thermal expansion is not always a nuisance; it has many useful applications in daily life and industry. For example, thermal expansion is used in thermometers to measure temperature, and in bimetallic strips for automatic temperature control devices. True. Borosilicate glass does not expand much on being heated because it has a very low coefficient of thermal expansion, making it resistant to thermal shock and cracking. False. The unit of heat and te…
- 17. False. Air is compressible. False. Liquids have no fixed shape but have fixed volume. False. Particles in solids are not free to move; they are tightly bound and can only vibrate about fixed positions. False. When pulses are washed with water before cooking, the water is separated from them by the process of decantation, not filtration. False. A strainer is a kind of sieve which is used to separate a solid from a liquid. True. Grain and husk can be separated by winnowing. False. Air is a mixture, not a pure substance, as it contains nitrogen, oxygen, argon, carbon dioxide, and other gases. False. Butter from curds is separated by churning, which involves vigorous agitation to separate the…
- 18. True, True, True, False, True. A cell is indeed the smallest unit of life capable of independent functioning. The nerve cell is the longest cell found in living organisms, particularly in animals. Prokaryotes were the first form of life to appear on Earth, billions of years ago. However, organelles are not found inside all cells; they are found specifically inside eukaryotic cells such as plant and animal cells, but not in prokaryotic cells like bacteria. New cells are produced from existing cells through the process of cell division, as stated in the cell theory.
- 19. Voluntary muscles are under conscious control, are usually attached to bones as skeletal muscles and are striated, whereas involuntary muscles act without conscious control, are found in internal organs and the heart (smooth and cardiac muscle) and are controlled by the autonomic nervous system.
- 20. The two main types of ecosystems are terrestrial ecosystems and aquatic ecosystems. Terrestrial ecosystems are found on land and include forests, grasslands, deserts, and mountains where organisms are adapted to living on soil with varying amounts of rainfall and temperature. Aquatic ecosystems are found in water bodies such as oceans, rivers, lakes, and ponds where organisms are adapted to living in freshwater or saltwater environments with specific conditions of light, temperature, and dissolved oxygen.
- 21. Artificial magnets are magnets that are made by humans through various manufacturing processes, as opposed to natural magnets found in nature. Common examples of artificial magnets include bar magnets, which are rectangular in shape and commonly used in laboratories and classrooms, and horseshoe magnets, which are curved in shape and provide strong magnetic fields at their poles. These man-made magnets are created by magnetizing ferromagnetic materials like iron and are widely used in scientific experiments, educational demonstrations, and practical applications.
- 22. (refer textbook)
- 23. A robot is a machine capable of carrying out a complex series of actions automatically, either independently or under the control of a human operator. Robots are programmed to perform specific tasks with precision and consistency. They can be designed for various purposes such as manufacturing, exploration, medical assistance, or household work. Robots operate based on programmed instructions and sensors that allow them to interact with their environment and complete assigned tasks efficiently.
- 24. Monocotyledonous plants are those that have a single cotyledon or seed leaf, and examples include grass, paddy, and maize. These plants typically have parallel leaf venation, fibrous root systems, and flower parts in multiples of three. Dicotyledonous plants are those that have two cotyledons or seed leaves, and examples include bean, mango, and neem. These plants typically have reticulate or net-like leaf venation, taproot systems, and flower parts in multiples of four or five. These two groups represent the two major classes of flowering plants.
- 25. Inorganic fertilizers are called so because they are manufactured fertilizers prepared by using natural elements that undergo chemical changes and processing in laboratories and industrial facilities. Unlike organic fertilizers which are derived from natural decomposition, inorganic fertilizers are synthetically produced through chemical reactions and processes to create concentrated forms of essential nutrients like nitrogen, phosphorus, and potassium in specific proportions for agricultural use.
- 26. The correct sequence of the respiratory pathway through which air travels is: Nostrils → Nasal cavity → Pharynx → Larynx → Trachea → Bronchi → Bronchiole → Alveolus. Air enters through the nostrils and passes through the nasal cavity where it is filtered, warmed, and moistened. It then travels through the pharynx and larynx before reaching the trachea, which branches into two bronchi. Each bronchus further divides into smaller bronchioles, which finally terminate in tiny air sacs called alveoli where gas exchange occurs.
- 27. Thermal equilibrium is the state reached when two objects in thermal contact no longer exchange heat energy and therefore no longer affect each other's temperature. When two objects at different temperatures are brought into contact, heat flows from the hotter object to the cooler object until both objects reach the same temperature. Once they reach the same temperature, there is no net flow of heat between them, and they are said to be in thermal equilibrium. At this point, both objects have the same thermal energy and will remain at the same temperature as long as they are not exposed to external heat sources or sinks.
- 28. Neem is used as a natural pesticide and insect repellent, as an antiseptic and remedy for skin infections, in dental care products and traditional medicines, for preparing neem oil used in cosmetics and soaps, and in agroforestry for shade and soil improvement.
- 29. Cell — pair of short and long parallel lines; Battery — two or more cells shown as repeated short and long lines; Wire — straight line; Switch — break in the line with a pivot; Bulb — circle with a cross inside; Resistor — zigzag line; Ammeter — circle with letter A; Voltmeter — circle with letter V.
- 30. The principal nutrients required for plant growth are nitrogen, phosphorus, and potassium, commonly abbreviated as NPK. Nitrogen (N) is essential for leaf and stem growth and gives plants their green colour. Phosphorus (P) is important for root development, flowering, and seed formation. Potassium (K) helps in overall plant health, disease resistance, and fruit quality. These three nutrients are the most important macronutrients that must be present in adequate quantities in fertilizers for optimal plant growth and crop production.
- 31. To identify the poles of an unlabelled bar magnet using iron filings, place the bar magnet on a surface and sprinkle iron filings around it. A large number of iron filings will stick to the two ends of the bar magnet, indicating the locations of the poles. The poles are the regions where the magnetic force is concentrated and strongest. The poles attract significantly more iron filings compared to the middle section of the magnet because the magnetic field is most intense at the poles. The poles have the highest magnetic strength, which is why they attract a dense cluster of iron filings. In contrast, the central region of the magnet has a much weaker magnetic field and attracts fewer iro…
- 32. True False – The geographical features and environmental conditions on earth do not remain the same from one place to another. True True False – Paramecium is a unicellular organism.
- 33. Electromagnets are used in electromagnetic trains. Electromagnets are magnetised when current flows through them. When the direction of the current is changed, poles will be changed. Magnets are attached at the bottom of the train and rail tracks. The train is lifted from track up to 10 cm height by the property of the same poles repel each other. By using attraction and repulsion at the same time between the magnets in tracks and bottom of train move forward. The magnets are controlled by electricity. There is no friction. So the train can easily attain a speed of 300 km/ h.
Brain Grain · braingrain.in
Science — Practice Paper · Set 2
Class: 6Samacheer KalviMax Marks: 57
Name: ____________________Reg No: ____________
Part I — Multiple Choice Questions 10 × 1 = 10
Choose the correct answer. (Answer all questions.)
1.The pond is an example of ………A. Marine habitatB. Freshwater habitatC. DesertsD. Mountain[1]
2.Which one of the following is an input device?A. SpeakerB. KeyboardC. MonitorD. Printer[1]
3.One day in 1922, the air temperature was measured at 59°C in the shade in Libya ________A. AmericaB. AfricaC. AntarcticaD. Europe[1]
4.Kangaroo rat lives In _______A. Aquatic habitatB. Desert habitatC. Grass land habitatD. Mountain habitat[1]
5.Magnets lose their properties when they areA. usedB. storedC. hit with a hammerD. cleaned[1]
6.Which are the source of food and energy for all living organisms in the world.A. Plants onlyB. Plants and animalsC. Animals onlyD. None of the above[1]
7.The first cell formed in the earthA. Eukaryotic cellB. Algal cellC. Fungal cellD. Prokaryotic cell[1]
8.Which of the following are characteristics of living beings? (i) Respiration (ii) Reproduction (iii) Adaptation (iv) Excretion Choose the correct sequenceA. (i), (ii), and (iv) onlyB. (i), (ii) onlyC. (ii) and (iv)onlyD. (i), (iv), (ii) and (iii)[1]
9.Gypsum is added to the cement for ………..A. fast settingB. delayed settingC. hardeningD. making paste[1]
10.Our body needs for muscle-buildingA. CarbohydrateB. fatC. ProteinD. Water[1]
Part II — Fill in the Blanks 5 × 1 = 5
Fill in the blanks. (Answer all questions.)
11.78% of air : Does not support combustion :: ……… : Supports combustion[1]
12.Curdling of milk : irreversible change :: Formation of clouds : ……….. change[1]
13.Matter is made up of ……… In solids, the space between the particles is less than in ………. Grains can be separated from their stalks by ………. Chillies are removed from ‘upma’ by ……… method. The method employed to separate clay particles from water is ………. Among the following items: Safety pins, pencil and rubber band, ………. will get attracted to a magnet. Water obtained from tube wells is usually ………. water[1]
14.The instrument used to observe the cell is ……….. I control the food production of a cell. Who am I? ……….. I am like a policeman. Who am I ………? The Term “cell” was coined by ……….. The egg of an Ostrich is the ……….. single cell.[1]
15.SI unit of length is symbolically represented as ……….. 500 gm = …………. kilogram. Distance between Delhi and Chennai can be measured in ………. 1 m = ………. cm. 5 km = ………. m.[1]
Part III — True or False 3 × 1 = 3
Write True or False. (Answer all questions.)
16.A cell is the smallest unit of life. Nerve cell is the longest cell Prokaryotes were the first form of life on earth. The organelles of both plants and animals are made up of cells. (Organelles – Found inside the cell) New cells are produced from existing cells.[1]
17.Heat is a kind of energy that flows from a hot body to a cold body. Steam is formed when heat is released from water. Thermal expansion is always a nuisance. Borosilicate glass do not expand much on being heated. The unit of heat and temperature are the same.[1]
18.Air is not compressible. Liquids have no fixed volume but have fixed shape. Particles in solids are free to move. Then pulses are washed with water before cooking, the water is separated from them by the process of filtration. Strainer is a kind of sieve which is used to separate a liquid from solid Grain and husk can be separated by winnowing Air is a pure substance Butter from curds is separated by sedimentation.[1]
Part IV — Short Answer Questions 12 × 2 = 24
Answer briefly. (Answer all questions.)
19.Hen Egg, Ostrich egg, Insect egg.[2]
20.Define measurement.[2]
21.Give an example of inorganic fertilizer.[2]
22.What are the essential components of a cell?[2]
23.Can deforestation be considered a desirable change? Explain.[2]
24.What is the clock used to measure the time accurately?[2]
25.Classify the Fibre yielding plants based on use.[2]
26.1 Metre, 1 Centimetre, 1 Kilometre, and 1 Millimetre.[2]
27.What are non-magnetic substances?[2]
28.What are the types of software?[2]
29.Define a slow change.[2]
30.Gaps are left in between rails while laying a railway track.[2]
Part V — Long Answer Questions 3 × 5 = 15
Answer in detail. (Answer all questions.)
31.Take out of cooled bottle of water from refrigerator and keep it on a table. After some time you notice a puddle of water around it. Why?[5]
32.Can you produce electricity from a lemon?[5]
33.What should be done if the clothes of a person catch fire accidentally? Why?[5]
🔑 Show Answer Key — Set 2
- 1. (b) Freshwater habitat
- 2. (b) Keyboard
- 3. (b) Africa
- 4. (b) Desert habitat
- 5. (c) hit with a hammer
- 6. (a) Plants only
- 7. (d) Prokaryotic cell
- 8. (d) (I), (iv), (il) and (iii)
- 9. b. delayed setting
- 10. (c) Protein
- 11. 21% of air
- 12. reversible
- 13. Atoms An Liquids Threshlng Hand picking Filtration Safety pins Impure
- 14. Microscope Chloroplast Cell membrane Robert Hooke Largest
- 15. metre 0.5 Kilometre 100 5000
- 16. True, True, True, False, True. A cell is indeed the smallest unit of life capable of independent functioning. The nerve cell is the longest cell found in living organisms, particularly in animals. Prokaryotes were the first form of life to appear on Earth, billions of years ago. However, organelles are not found inside all cells; they are found specifically inside eukaryotic cells such as plant and animal cells, but not in prokaryotic cells like bacteria. New cells are produced from existing cells through the process of cell division, as stated in the cell theory.
- 17. True. Heat is a kind of energy that flows from a hot body to a cold body. False. Steam is formed when heat is absorbed by water, not released from it. During the process of vaporization, water molecules gain energy and escape as steam. False. Thermal expansion is not always a nuisance; it has many useful applications in daily life and industry. For example, thermal expansion is used in thermometers to measure temperature, and in bimetallic strips for automatic temperature control devices. True. Borosilicate glass does not expand much on being heated because it has a very low coefficient of thermal expansion, making it resistant to thermal shock and cracking. False. The unit of heat and te…
- 18. False. Air is compressible. False. Liquids have no fixed shape but have fixed volume. False. Particles in solids are not free to move; they are tightly bound and can only vibrate about fixed positions. False. When pulses are washed with water before cooking, the water is separated from them by the process of decantation, not filtration. False. A strainer is a kind of sieve which is used to separate a solid from a liquid. True. Grain and husk can be separated by winnowing. False. Air is a mixture, not a pure substance, as it contains nitrogen, oxygen, argon, carbon dioxide, and other gases. False. Butter from curds is separated by churning, which involves vigorous agitation to separate the…
- 19. The correct order from smallest to largest is: Insect egg, Hen egg, Ostrich egg. Insect eggs are typically microscopic or very small in size. Hen eggs are medium-sized eggs that we commonly use in our daily lives. Ostrich eggs are the largest eggs among birds and are significantly bigger than hen eggs.
- 20. Measurement is the comparison of an unknown quantity with some known quantity of the same kind. It involves using a standard unit or scale to determine the size, length, mass, volume, or other properties of an object or substance. Measurement is fundamental to science and everyday life as it allows us to quantify and compare different things accurately.
- 21. Examples of inorganic fertilizers include urea, which is a nitrogen-rich fertilizer commonly used to provide nitrogen to plants; ammonium sulphate, which supplies both nitrogen and sulphur to the soil; and superphosphate, which is a phosphorus-rich fertilizer that provides phosphorus for plant growth. These inorganic fertilizers are manufactured chemically and provide essential nutrients in concentrated forms that are readily available for plant absorption, making them effective for increasing crop yield and plant growth.
- 22. A typical cell consists of three major parts. The first is the cell membrane, which is an outer protective layer that controls the movement of substances in and out of the cell. The second is the cytoplasm, which is a liquid substance inside the cell that contains various organelles and where most cellular activities occur. The third is the nucleus, which is a membrane-bound structure that contains the cell's genetic material in the form of DNA and controls the cell's activities and reproduction.
- 23. Deforestation cannot be considered a desirable change because it is harmful to our environment and is not desired by us. Deforestation is classified as an undesirable change. When forests are cut down, it leads to loss of habitat for wildlife, reduces oxygen production, increases carbon dioxide in the atmosphere, causes soil erosion, disrupts the water cycle, and contributes to climate change. Deforestation also destroys the natural resources and biodiversity that forests provide. Therefore, it is a change that has negative consequences for both the environment and human society.
- 24. An electronic clock or a stop clock is used to measure time accurately. An electronic clock provides precise digital or analog time display with high accuracy, while a stop clock is specifically designed to measure short time intervals with precision, making it useful for timing experiments and activities in scientific work.
- 25. Fibre-yielding plants can be classified into three main categories based on their use. The first category is textile fibres, which are used to make cloth and clothing. Cotton is the most important textile fibre, widely used in the textile industry to produce various types of fabrics and garments. The second category is cordage fibres, which are used to make ropes, twines, and other cordage products. Coconut fibre, also known as coir, is a major cordage fibre obtained from the husk of coconut and is used for making ropes, mats, and brushes. The third category is filling fibres, which are used as stuffing material in pillows, mattresses, and cushions. Silk cotton is an important filling fib…
- 26. In order from smallest to largest, the units of length are arranged as follows: 1 millimetre, 1 centimetre, 1 metre, and 1 kilometre. A millimetre is the smallest unit among these, followed by the centimetre which is 10 times larger than a millimetre. A metre is 100 times larger than a centimetre, and a kilometre is 1000 times larger than a metre. This arrangement helps us understand the relative sizes of different length measurements used in various contexts.
- 27. Substances which are not attracted by magnets are called non-magnetic substances. These materials do not respond to magnetic forces and cannot be magnetized under normal circumstances. Common examples of non-magnetic substances include paper, plastic, wood, glass, rubber, and cloth. Non-magnetic substances lack the atomic properties necessary to interact with magnetic fields. Even when placed very close to a magnet, these materials show no attraction or repulsion. Understanding the difference between magnetic and non-magnetic substances helps us identify which materials can be separated using magnets in practical applications.
- 28. Software is divided into two main types based on its function and purpose. The first type is System Software, which includes the Operating System. System software manages the computer's hardware and provides a platform for other programs to run. The second type is Application Software, which consists of programs designed for specific tasks that end-users perform on their computers. Application software includes programs like word processors, web browsers, games, and educational tools. While system software works behind the scenes to manage the computer, application software is directly used by people to accomplish their work and tasks.
- 29. A slow change is a change that takes place over a long period of time, such as hours, days, months, or even years. These changes occur gradually and are not immediately noticeable at any given moment, but become evident when observed over an extended duration. Examples of slow changes include the growth of a child, rusting of iron, decaying of plants, germination of seeds, and ripening of fruits. Slow changes are in contrast to fast changes, which occur very quickly in seconds or minutes.
- 30. Gaps are left in between rails while laying a railway track to allow space for thermal expansion. During summer, when the temperature increases, the metal rails undergo thermal expansion and increase in length. If no gaps were provided between the rails, the expanding rails would push against each other, creating enormous internal stress and pressure. This stress could cause the rails to buckle, bend, or warp, making the railway track unsafe for trains. The gaps provide the necessary space for the rails to expand freely without causing damage to the track structure.
- 31. When a cooled bottle of water is taken out of the refrigerator and kept on a table, a puddle of water forms around it after some time due to the process of condensation. The cooled surface of the bottle has a temperature lower than the surrounding air. This cold surface cools the air in contact with it, reducing the temperature of the air around the bottle. When air is cooled, its capacity to hold water vapour decreases, causing the water vapour present in the air to condense into liquid water droplets. These water droplets accumulate on the outer surface of the bottle and eventually drip down to form a puddle of water on the table. This is a common example of condensation occurring in ou…
- 32. Yes, we can produce electricity from a lemon using it as a simple electrochemical cell. To create a lemon cell, insert a copper plate on one side of the lemon and a zinc strip or safety pin on the other side. The lemon juice acts as an electrolyte containing ions that allow chemical reactions to occur between the two different metals. The copper plate serves as the positive terminal and the zinc strip or safety pin serves as the negative terminal. When you connect the two terminals with connecting wires to an electric bulb or other load, a small electric current flows through the circuit due to the chemical reaction inside the lemon. This current is sufficient to make a small bulb glow di…
- 33. If the clothes of a person catch fire accidentally, immediate action should be taken to extinguish the flames. The person should be covered with a rug, blanket, or any available cloth material and then rolled on the floor. This method works because covering the person cuts off the supply of oxygen to the fire, and since fire requires oxygen to burn, the flames will be extinguished. Rolling on the floor also helps to smother the flames and prevent them from spreading. Alternatively, a suitable fire extinguisher can be used if available nearby. It is important not to run around as this will fan the flames and make the fire worse. Quick action and keeping calm are essential in such emergency…
Brain Grain · braingrain.in
Science — Practice Paper · Set 3
Class: 6Samacheer KalviMax Marks: 57
Name: ____________________Reg No: ____________
Part I — Multiple Choice Questions 10 × 1 = 10
Choose the correct answer. (Answer all questions.)
1.Calcium is an example of aA. CarbohydrateB. fatC. ProteinD. minerals[1]
2.Bacteria are very small microorganism.A. ProkaryoticB. EukaryoticC. Protozoa AcellularD. Acellular[1]
3.Organs of absorption are ………A. RootB. StemC. LeafD. Flower[1]
4.Here heat energy is converted into electric energyA. Thermal power stationB. Atomic power stationC. Hydel power stationD. Windmills[1]
5.How earth revolves?A. From west to eastB. east to westC. From north to southD. south to west.[1]
6.Plants grown or maintained for its aesthetic features are known asA. Fibre plantsB. Medicinal plantsC. Plants as foodD. Ornamental plants[1]
7.Breakdown of food into smaller molecules in our body is known asA. Muscle contractionB. RespirationC. DigestionD. Excretion[1]
8.The stalk of the leaf is knownA. peduncleB. rachisC. pedicelD. petiole[1]
9.Seeds from water-melon can be removed by method.A. Hand-pickingB. filtrationC. magnetic separationD. decantation[1]
10.A _____ device helps to enter input information.A. HardwareB. SoftwareC. MonitorD. Modem[1]
Part II — Fill in the Blanks 5 × 1 = 5
Fill in the blanks. (Answer all questions.)
11.In every year October ……….is celebrated as world food day. ………… is an example of textile fibre. I am the state tree of Tamilnadu. Who am I ………… ? The juice of the leaves of ……… plant relieves cough and bronchitis. The edible seeds of leguminous plants are called …………[1]
12.Magnet attracts iron needle. This is ……… change, (a reversible / an irreversible) Boiling of egg results in ………… change, (a reversible / an irreversible) Changes that are harmful to us are ………… (desirable / undesirable) Plants convert Carbon-di-oxide and water into starch. This is an example of ………. change, (natural / human made) Bursting of fire crackers is a ……….. change whereas germination of seeds is a ………. change, (slow / fast)[1]
13.Burning of matchstick: ………… change :: Rotation of the Earth : Slow change[1]
14.Tropical rain forests, grasslands, and deserts are known as ……….. Some living things are made of a single cell, they are called a……….. organism The breathing organ of a fish is known as ……….. The lizard ……….. on the ground with its claw on its feet. Camel stores ………… in its hump.[1]
15.A group of organs together make up an ………. system. The part of the skeleton that protects the brain is ………… The process by which the body removes waste is ……….. The ………. is the largest sense organ in our body. The endocrine glands produce chemical substances called …………[1]
Part III — True or False 3 × 1 = 3
Write True or False. (Answer all questions.)
16.Air is not compressible. Liquids have no fixed volume but have fixed shape. Particles in solids are free to move. Then pulses are washed with water before cooking, the water is separated from them by the process of filtration. Strainer is a kind of sieve which is used to separate a liquid from solid Grain and husk can be separated by winnowing Air is a pure substance Butter from curds is separated by sedimentation.[1]
17.A cell is the smallest unit of life. Nerve cell is the longest cell Prokaryotes were the first form of life on earth. The organelles of both plants and animals are made up of cells. (Organelles – Found inside the cell) New cells are produced from existing cells.[1]
18.Heat is a kind of energy that flows from a hot body to a cold body. Steam is formed when heat is released from water. Thermal expansion is always a nuisance. Borosilicate glass do not expand much on being heated. The unit of heat and temperature are the same.[1]
Part IV — Short Answer Questions 12 × 2 = 24
Answer briefly. (Answer all questions.)
19.What are the medicinal plants?[2]
20.The motion of an object travels equal distances in equal intervals of time.[2]
21.What are the three types of blood vessels?[2]
22.Define mass.[2]
23.List out the types of forces on the basis of contact.[2]
24.Iron, nail, pins, rubber tube, needle[2]
25.Differentiate between unicellular and multicellular organisms.[2]
26.You are given some candle wax. Can you make a candle doll from it? What kind of change is this?[2]
27.Write short notes on-Timber yielding plants.[2]
28.The electric wire which sag in summer become straight in winter.[2]
29.The motion which repeats itself after a fixed interval of time.[2]
30.What are the two different types of molecules found in the soap?[2]
Part V — Long Answer Questions 3 × 5 = 15
Answer in detail. (Answer all questions.)
31.Write the importance of the food chain.[5]
32.Which of the changes can be reversed? Justify your answer.[5]
33.Plants grown for decorative purposes are called as softwood. Silkworm eats mulberry leaves. Cauliflower is used for ornamental purpose. Cotton cloth is not suitable for summer season. Sugarcane is used as biofuel.[5]
🔑 Show Answer Key — Set 3
- 1. (d) minerals
- 2. (a) prokaryotic
- 3. (a) Root
- 4. (a) Thermal power station
- 5. (a) From west to east
- 6. (d) Ornamental plants
- 7. (a) Digestion
- 8. (d) petiole
- 9. (c) Hand picking
- 10. (a) Hardware
- 11. 16 Cotton Palm tree Tulsi pulses
- 12. a reversible an irreversible undesirable Natural fast; slow
- 13. Fast
- 14. habitat unicellular gills walk and run fat
- 15. Organ Skull Excretion Skin hormones
- 16. False. Air is compressible. False. Liquids have no fixed shape but have fixed volume. False. Particles in solids are not free to move; they are tightly bound and can only vibrate about fixed positions. False. When pulses are washed with water before cooking, the water is separated from them by the process of decantation, not filtration. False. A strainer is a kind of sieve which is used to separate a solid from a liquid. True. Grain and husk can be separated by winnowing. False. Air is a mixture, not a pure substance, as it contains nitrogen, oxygen, argon, carbon dioxide, and other gases. False. Butter from curds is separated by churning, which involves vigorous agitation to separate the…
- 17. True, True, True, False, True. A cell is indeed the smallest unit of life capable of independent functioning. The nerve cell is the longest cell found in living organisms, particularly in animals. Prokaryotes were the first form of life to appear on Earth, billions of years ago. However, organelles are not found inside all cells; they are found specifically inside eukaryotic cells such as plant and animal cells, but not in prokaryotic cells like bacteria. New cells are produced from existing cells through the process of cell division, as stated in the cell theory.
- 18. True. Heat is a kind of energy that flows from a hot body to a cold body. False. Steam is formed when heat is absorbed by water, not released from it. During the process of vaporization, water molecules gain energy and escape as steam. False. Thermal expansion is not always a nuisance; it has many useful applications in daily life and industry. For example, thermal expansion is used in thermometers to measure temperature, and in bimetallic strips for automatic temperature control devices. True. Borosilicate glass does not expand much on being heated because it has a very low coefficient of thermal expansion, making it resistant to thermal shock and cracking. False. The unit of heat and te…
- 19. Medicinal plants are plants that possess healing properties and are used to treat, cure, or prevent diseases and health conditions. These plants contain various chemical compounds and active ingredients that have therapeutic effects on the human body. Examples of common medicinal plants include neem, which has antibacterial properties, tulsi or holy basil used for respiratory health, turmeric known for its anti-inflammatory properties, and aloe vera used for skin healing. Many traditional and modern medicines are derived from these plants. Medicinal plants have been used for centuries in various cultures and continue to be an important source of pharmaceutical compounds and natural remedies.
- 20. Uniform motion is the motion of an object that travels equal distances in equal intervals of time. In uniform motion, the speed of the object remains constant throughout its journey, meaning the object covers the same amount of distance in every unit of time. For example, if a car travels 60 kilometers in one hour, and continues to travel 60 kilometers in every subsequent hour, it is said to be in uniform motion. The velocity remains constant in uniform motion, and the object moves in a straight line without any change in speed or direction.
- 21. The three types of blood vessels are arteries, veins, and capillaries. Arteries carry blood away from the heart to various parts of the body under high pressure. Veins carry blood back to the heart from different parts of the body under low pressure. Capillaries are very thin, microscopic blood vessels that connect arteries and veins, allowing exchange of nutrients, oxygen, and waste products between blood and body cells.
- 22. Mass is the measure of the amount of matter in an object. It is an intrinsic property of an object that remains constant regardless of its location or the gravitational field acting on it. Mass is different from weight, which depends on gravity. The SI unit of mass is the kilogram.
- 23. On the basis of contact, forces are classified into two main types. Contact forces are forces that act when two objects are in direct physical contact with each other, such as when you kick a ball or push a door. Non-contact forces are forces that can act on an object from a distance without any direct physical contact between the objects, such as gravitational force between the Earth and objects, magnetic force between magnets, and electrostatic force between charged objects. These two categories represent the fundamental ways in which forces can be applied to objects.
- 24. Iron, nails, pins, and needles are magnetic substances because they are attracted to magnets and can be magnetized. Rubber tube is a non-magnetic substance because it is not attracted to magnets and cannot be magnetized. Magnetic substances are typically made of iron or iron-based materials, while non-magnetic substances like rubber, plastic, and wood do not respond to magnetic forces.
- 25. Unicellular organisms consist of a single cell that performs all life functions and are usually microscopic, whereas multicellular organisms are made of many specialized cells that perform different functions, allowing greater size and complexity.
- 26. Yes, you can make a candle doll from candle wax by reshaping it into the desired form. This is a physical change because only the shape and form of the wax are altered, while the material itself remains candle wax. The chemical composition and properties of the wax do not change. Additionally, this change is reversible because the wax doll can be melted again and reshaped into any other form, including back into a candle. Physical changes involve only changes in appearance, shape, size, or state of matter without altering the fundamental nature of the substance.
- 27. Timber-yielding plants are trees that produce wood suitable for commercial and industrial use. Wood from these plants is valued for its durability, which allows it to withstand wear and tear over long periods. Timber also offers stylish finishing possibilities, making it aesthetically appealing for furniture and decorative purposes. Additionally, timber has good resistance to temperature changes, making it suitable for various climatic conditions. Timber is classified into two main categories: hardwoods and softwoods. Hardwoods come from deciduous trees and are dense, strong, and durable, making them suitable for heavy construction and furniture. Softwoods come from coniferous trees and a…
- 28. During summer, the electric wire experiences thermal expansion due to the increase in temperature. The heat causes the molecules in the wire to vibrate more vigorously and move farther apart, resulting in an increase in the length of the wire. This causes the wire to sag between the poles. In winter, when the temperature decreases, the wire contracts as the molecules move closer together and vibrate less. This contraction reduces the length of the wire, making it become straight again.
- 29. Oscillatory motion is the motion of an object that repeats itself after a fixed interval of time, moving back and forth along the same path. In oscillatory motion, the object returns to its starting position after completing one full cycle. Common examples include the swinging of a pendulum, the vibration of a tuning fork, and the motion of a child on a swing. The time taken to complete one full cycle is called the period of oscillation.
- 30. The two different types of molecules found in soap are water-loving molecules, also called hydrophilic molecules, which have an affinity for water and are attracted to water molecules, and water-hating molecules, also called hydrophobic molecules, which repel water and are attracted to oils and fats. The water-loving end of the soap molecule is ionic and polar, while the water-hating end is non-polar and resembles the structure of oil molecules. This dual nature of soap molecules allows them to interact with both water and oil, making soap an effective cleaning agent that can remove dirt and oil from surfaces and fabrics.
- 31. The food chain is important for understanding the structure and functioning of ecosystems in several ways. Learning about food chains helps us understand the feeding relationships and interactions between different organisms in any ecosystem, showing how energy and nutrients move from one organism to another. It enables us to appreciate the energy flow through different trophic levels, from producers to primary, secondary, and tertiary consumers, and understand how energy is transferred and lost at each level. Food chains also help us understand nutrient circulation in ecosystems, showing how essential elements like carbon, nitrogen, and phosphorus cycle through living and non-living comp…
- 32. Many changes around us can be reversed. When a candle is burning, the heat of the flame melts the solid wax into liquid wax. This is a reversible or physical change because the wax can be cooled and solidified back into a solid state, though it may take a different shape. Similarly, when ice melts into water due to heat, it can be frozen back into ice by cooling. Water can evaporate and then condense back into liquid form. These changes are reversible because the substance returns to its original state or form through a change in physical conditions like temperature, without any permanent alteration in the nature of the material. The key characteristic of reversible changes is that they d…
- 33. False – Plants grown for decorative purposes are called as ornamental plants. True. False – Cauliflower is used for edible purpose. False – Cotton cloth is only suitable for summer season False – Sugarcane is used to produce sugar.