Natural Science MCQs

Questions and Answers (61–90)

61. What is the chemical symbol for gold?

Answer: Au

62. Which organ produces insulin?

Answer: Pancreas

63. What is the unit of electric power?

Answer: Watt

64. Which planet is the hottest in the solar system?

Answer: Venus

65. What is the process by which plants lose water through leaves?

Answer: Transpiration

66. Which element is necessary for hemoglobin formation?

Answer: Iron

67. What type of lens is used in a magnifying glass?

Answer: Convex lens

68. Which gas is used by plants during photosynthesis?

Answer: Carbon dioxide

69. What is the SI unit of density?

Answer: kg/m³

70. Which organ helps maintain body balance?

Answer: Inner ear

71. What is the study of the universe called?

Answer: Astronomy

72. Which vitamin is important for blood clotting?

Answer: Vitamin K

73. What is the speed of sound in air?

Answer: About 343 m/s

74. What is the largest desert on Earth?

Answer: Antarctica

75. Which metal is used in thermometers?

Answer: Mercury

76. Which part of the plant conducts water upward?

Answer: Xylem

77. What is the unit of electric charge?

Answer: Coulomb

78. Which planet is known as the Blue Planet?

Answer: Earth

79. What is the process by which a solid changes directly into gas?

Answer: Sublimation

80. Which blood cells help in clotting?

Answer: Platelets

81. Which organ is responsible for pumping blood?

Answer: Heart

82. What is the chemical formula of carbon dioxide?

Answer: CO₂

83. Which planet has the shortest year?

Answer: Mercury

84. Which scientist discovered the electron?

Answer: J. J. Thomson

85. What is the unit of magnetic field strength?

Answer: Tesla

86. Which organ helps in filtering blood?

Answer: Kidneys

87. Which part of the Earth supports life?

Answer: Biosphere

88. What is the process of breaking food into simpler substances?

Answer: Digestion

89. Which element is essential for photosynthesis?

Answer: Magnesium

90. What is the unit of luminous intensity?

Answer: Candela