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1. A group of similar cells combine together to form
   A. Organ
   B. System
   C. Body
   D. Tissue ✅

2. The enlargement of image is called
   A. Embroidery
   B. Modification
   C. Magnification ✅
   D. Abbreviation

3. Periscope is an optical instrument that works on the principle of total
   A. Internal reflection ✅
   B. External refraction
   C. Internal reflex
   D. Zero reflection

4. If the fundamental frequency of a guitar string is 220 Hz, the frequency of the second harmonic is
   A. 110 Hz
   B. 220 Hz
   C. 440 Hz ✅
   D. 880 Hz

5. A reflecting telescope consists of
   A. A primary and secondary mirror ✅
   B. Only a single mirror
   C. Many lenses
   D. A prism of split light

6. The phenomenon, which leads to the destruction of man-made structure and metal of archaeological importance is
   A. Tsunami
   B. Flood
   C. Greenhouse effect
   D. Acid rain ✅

7. The step which can save the earth and natural resources is
   A. Tree Plantation ✅
   B. Deforestation
   C. Gas engines in the air
   D. Wastage of water

8. Pneumatic systems are used in
   A. Spray Guns
   B. Pumps
   C. Dentistry tools
   D. All of the above ✅

9. The depletion of the following gas is mainly responsible for ozone depletion:
   A. Carbon dioxide
   B. Chlorofluorocarbon ✅
   C. Oxygen
   D. Sulfur Dioxide

10. The density of water is
    A. 1 g/cm³ ✅
    B. 1.5 g/cm³
    C. 2.5 g/cm³
    D. 0.5 g/cm³

11. Our galaxy is __ in shape.
    A. Spherical
    B. Elliptical
    C. Spiral ✅
    D. Irregular

12. One horse power is equal to
    A. 766 m/sec
    B. 746 watt ✅
    C. 714 newton
    D. 764 joule

13. Which of the following harmonics are two octaves higher in pitch than the fundamental?
    A. First
    B. Second
    C. Third
    D. Fourth ✅

14. Name the vitamin whose gene is inserted in rice plant for creating genetically modified rice variety
    A. Vitamin A ✅
    B. Vitamin B
    C. Vitamin C
    D. Vitamin K

15. Which of the following equations represents a decomposition reaction?
    A. A + B → AB
    B. AC + BC → AC + B
    C. AB → A + B ✅
    D. AC + BA → 2A + BC

16. The metallic oxides are called
    A. Acids
    B. Bases ✅
    C. Neutral
    D. Weak oxides

17. The atoms ¹²C and ¹⁴C have the same
    A. Number of protons ✅
    B. Number of electrons
    C. Number of neutrons
    D. Atomic mass

18. The color of Sulphur powder is
    A. White
    B. Colorless
    C. Green
    D. Yellow ✅

19. The transfer of pollen of a flowering plant to the stigma part from another flower is called
    A. Pollination ✅
    B. Fertilization
    C. Seed formation
    D. Fermentation

20. The bulge of the greater curvature of the stomach superior to the esophageal junction is the
    A. Pylorus
    B. Fundus ✅
    C. Antrum
    D. Cardia

21. The study of internal structure of Earth is called
    A. Geobiology
    B. Geophysics ✅
    C. Astrophysics
    D. Thermodynamics

22. The quantities that cannot be explained in terms of other quantities are known as
    A. Fundamental physical quantities ✅
    B. Chemical quantities
    C. Energy materials
    D. Non-basic quantities

23. Which fluid is used in hydraulic power systems?
    A. Water
    B. Oil
    C. Non-compressible fluid
    D. All of the above ✅

24. Which of the following does not make use of expansion and contraction?
    A. An electric fan ✅
    B. An electric iron
    C. A thermometer
    D. A railway track

25. A bimetallic strip is used in
    A. An electric fan
    B. An electric iron ✅
    C. A thermometer
    D. A railway track

26. Which of the following helps to change the shape of the lens in the eye?
    A. Ciliary Muscle ✅
    B. Cornea
    C. Retina
    D. Iris

27. A thick layer of air that surrounds the Earth is known as
    A. Moisture
    B. Atmosphere ✅
    C. Earthquake
    D. Ozone

28. According to Pascal’s principle, the pressure applied at a point is equal in all directions of enclosed
    A. Fluid ✅
    B. Solid
    C. Gas
    D. Plasma

29. The study of the behavior and application of compressed air is called
    A. Pneumatic Technology ✅
    B. Biotechnology
    C. Aerospace Technology
    D. Nano Technology

30. A place of living according to particular environment of a living thing is
    A. Ecosystem
    B. Habitat ✅
    C. Biosphere
    D. Ecosphere

31. Area where river meets with sea is
    A. Freshwater
    B. Marine water
    C. Estuary ✅
    D. Delta

32. Oil can be changed into fat through the process of
    A. Oxidation
    B. Hydrogenation ✅
    C. Hydrolysis
    D. Polymerization

33. The ___ is made up of double helix of two complementary strands
    A. DNA ✅
    B. RNA
    C. Nucleus
    D. Golgi bodies

34. Water has maximum density at
    A. -4°C
    B. 0°C
    C. 25°C
    D. 4°C ✅

35. Infants and children should be immunized with BCG (Bacille Calmette-Guérin) vaccine against
    A. Tuberculosis (TB) ✅
    B. Malaria
    C. Measles
    D. Typhoid

36. Wavelength symbol “λ” is termed as
    A. Lambda ✅
    B. Eta
    C. Wavenumber
    D. Phi

37. Which structure prevents food from entering the larynx during swallowing?
    A. Pharynx
    B. Esophagus
    C. Epiglottis ✅
    D. Tongue

38. Zygote forms after the combination of
    A. Embryo
    B. Gametes ✅
    C. Body cells
    D. A & B

39. Pollen grains are microscopic structures located in the ___ of the flower
    A. Anther ✅
    B. Pistil
    C. Petal
    D. Sepal

40. Sound waves travel in solids in the form of
    A. Transverse waves
    B. Longitudinal waves ✅
    C. Stationary waves
    D. Both A and B

41. Why does a piece of bread become wet when chewed and taste sweet?
    A. Mouth ✅
    B. Esophagus
    C. Stomach
    D. Tongue
    ✔ Explanation: Saliva in the mouth contains amylase, an enzyme that breaks down starch into sugars, making the bread taste sweet.

42. Which is secreted by the liver and stored in the gallbladder?
    A. Saliva
    B. Gastric juice
    C. Bile ✅
    D. Pancreatic juice
    ✔ Explanation: Bile is produced by the liver and stored in the gallbladder. It helps emulsify fats during digestion.

43. Where does chemical digestion of proteins start?
    A. Mouth
    B. Esophagus
    C. Stomach ✅
    D. Small intestine
    ✔ Explanation: Protein digestion begins in the stomach, where the enzyme pepsin is secreted.

44. Fertilizers are used to fill the ___ requirements of plants.
    A. Reproductive
    B. Nutritional ✅
    C. Circulation
    D. Transportation
    ✔ Explanation: Fertilizers provide nutrients like nitrogen, phosphorus, and potassium (NPK) essential for plant growth.

45. The study of insects is called:
    A. Immunology
    B. Morphology
    C. Pharmacology
    D. Entomology ✅
    ✔ Explanation: Entomology is the branch of zoology concerned with the study of insects.

46. Cyanobacteria is also known as:
    A. Blue-green algae ✅
    B. Yellow-green algae
    C. Brown algae
    D. Red algae
    ✔ Explanation: Cyanobacteria are commonly called blue-green algae, known for their ability to photosynthesize.

47. Periods in the periodic table are:
    A. Horizontal rows ✅
    B. Vertical rows
    C. Both A and B
    D. Family
    ✔ Explanation: Periods are the horizontal rows in the periodic table.

48. Which system communicates and coordinates body functions?
    A. Skeletal system
    B. Nervous system ✅
    C. Respiratory system
    D. Digestive system
    ✔ Explanation: The nervous system is responsible for communication and coordination across the body.

49. Deoxyribonucleic acid is abbreviated as?
    A. RNA
    B. DNA ✅
    C. NDA
    D. DAC
    ✔ Explanation: DNA stands for Deoxyribonucleic Acid, which carries genetic instructions.

50. A curved transparent glass that refracts light is called?
    A. Fiber
    B. Lens ✅
    C. Gas
    D. Plastic
    ✔ Explanation: A lens is a transparent curved material that refracts light rays to converge or diverge them.