Title 6 Life Processes - MCQs.pdf ✅

© www.bankofbiology.com 8921 510 476 1 6. LIFE PROCESSES – MCQs and Answers WHAT ARE LIFE PROCESSES? 1. Life processes are the a) Activities that only involve growth and reproduction. b) Maintenance processes to prevent damage and break-down of an organism’s body. c) Activities that only involve nutrition and respiration. d) Processes that involve only excretion and movement. Answer: b) Maintenance processes to prevent damage and break-down of an organism’s body. 2. Most food sources are a) Carbon-based b) Water-based c) Mineral-based d) Sugar-based Answer: a) Carbon-based 3. What type of reactions are commonly used to break down molecules in the body? a) Neutralisation reactions b) Oxidising-reducing reactions c) Precipitation reactions d) Sublimation reactions Answer: b) Oxidising-reducing reactions 4. The process that removes useless and harmful by- products created by chemical reactions in cells is a) Respiration b) Nutrition c) Excretion d) Transportation Answer: c) Excretion 5. Unicellular organisms have no specific organs for food intake, gas exchange, or removal of wastes because a) They have a complex organ system. b) They have a very high metabolic rate. c) Their entire surface is in contact with the environment. d) They don’t perform these functions. Answer: c) Their entire surface is in contact with the environment. 6. Which of the following is not a role of the transportation system in multicellular organisms? a) To store food and oxygen. b) To transport oxygen. c) To carry food and oxygen to all body parts. d) To carry waste products from tissues to the excretory system. Answer: a) To store food and oxygen. NUTRITION 7. The process of transferring the energy source (food) from outside the body to the inside is called a) Respiration b) Excretion c) Nutrition d) Photosynthesis Answer: c) Nutrition 8. Which of the following is an example of a heterotroph? a) Green plants b) Cyanobacteria c) Animals d) Algae Answer: c) Animals 9. Photosynthesis is the process of a) Conversion of CO2 and water into carbohydrates in the presence of sunlight and chlorophyll b) Breakdown of carbohydrates into CO2 and water in the presence of sunlight and chlorophyll c) Absorption of water and minerals from the soil in the presence of sunlight and chlorophyll d) Conversion of sunlight into heat energy in the presence of sunlight and chlorophyll Answer: a) Conversion of CO2 and water into carbohydrates in the presence of sunlight and chlorophyll 10. Where are carbohydrates stored in plants when they are not immediately used? a) As glycogen b) As proteins c) As starch d) As fats Answer: c) As starch 11. What are the green dots observed in some cells of a leaf under a microscope? a) Mitochondria b) Chloroplasts c) Nuclei d) Ribosomes Answer: b) Chloroplasts 12. What is the first step in the process of photosynthesis? a) Reduction of CO2 to carbohydrates b) Splitting of water molecules into hydrogen and oxygen c) Absorption of light energy by chlorophyll d) Conversion of light energy to chemical energy Answer: c) Absorption of light energy by chlorophyll 13. Which experiment demonstrates that chlorophyll is essential for photosynthesis? a) Using a potted plant with variegated leaves and testing for starch

© www.bankofbiology.com 8921 510 476 3 28. What is the function of villi in the small intestine? a) To secrete digestive enzymes b) To increase the surface area for absorption c) To break down food particles d) To neutralize stomach acids Answer: b) To increase the surface area for absorption 29. The unabsorbed food in the human body is a) It is digested in the small intestine b) It is absorbed in the stomach c) It is moved to the large intestine where more water is absorbed d) It is broken down by bile juice Answer: c) It is moved to the large intestine where more water is absorbed 30. Gradual softening and demineralization of enamel and dentine by acids produced by bacteria leads to a) Dental caries b) Gingivitis c) Dental plaque d) Fluorosis Answer: a) Dental caries (tooth decay) 31. What forms dental plaque on teeth? a) Food particles and masses of bacterial cells b) Excessive saliva c) Lack of brushing d) High calcium content in the diet Answer: a) Food particles and masses of bacterial cells 32. How can dental plaque be removed? a) By avoiding sugary foods b) By drinking plenty of water c) By brushing teeth after eating d) By eating more fruits Answer: c) By brushing teeth after eating. RESPIRATION 33. Respiration is the a) Production of glucose in cells b) Oxidation of food material in cells to release energy c) Breakdown of carbon dioxide in cells d) Synthesis of proteins in cells Answer: b) Oxidation of food material in cells to release energy 34. What is the main product released during respiration in yeast? a) Carbon dioxide b) Oxygen c) Nitrogen d) Water Answer: a) Carbon dioxide 35. The first step of respiration in all organisms is the a) Conversion of pyruvate into lactic acid b) Breakdown of glucose into pyruvate c) Release of carbon dioxide d) Absorption of oxygen Answer: b) Breakdown of glucose into pyruvate 36. What is anaerobic respiration? a) Respiration in the presence of oxygen b) Respiration that produces a lot of energy c) Respiration in the absence of oxygen d) Respiration that only occurs in plants Answer: c) Respiration in the absence of oxygen 37. Which process occurs during fermentation in yeast? a) Conversion of glucose into pyruvate b) Conversion of pyruvate into ethanol & CO2 c) Breakdown of fatty acids d) Conversion of amino acids into proteins Answer: b) Conversion of pyruvate into ethanol & CO2 38. Muscle cramps occurs during sudden activity due to a) Accumulation of ethanol b) Accumulation of lactic acid c) Excess of oxygen in muscles d) Excess of ATP in muscles Answer: b) Accumulation of lactic acid 39. Where does aerobic respiration take place in the cell? a) Cytoplasm b) Nucleus c) Ribosomes d) Mitochondria Answer: d) Mitochondria 40. Which is the energy currency of the cell? a) ATP b) Glucose c) Pyruvate d) Lactic acid Answer: a) ATP 41. Through which structure do plants exchange gases? a) Roots b) Stomata c) Flowers d) Fruits Answer: b) Stomata 42. Which organ is the respiratory organ in fish? a) Lungs b) Skin c) Gills d) Trachea Answer: c) Gills 43. The human respiratory system includes a) Lungs and stomach b) Lungs and air passage c) Heart and lungs d) Kidneys and lungs Answer: b) Lungs and air passage 44. The collapsing of the air passage in humans is prevented by a) Muscles b) Skin c) Bones d) Cartilage rings Answer: d) Cartilage rings 45. Lung alveoli are
© www.bankofbiology.com 8921 510 476 4 a) Tiny tubules to conduct oxygen b) Cells where oxygen and CO2 exchange occurs c) Balloon-like structures where gas exchange occurs d) Structures that filter the air Answer: c) Balloon-like structures where gas exchange occurs 46. The main function of haemoglobin is a) To break down glucose b) To carry oxygen from the lungs to tissues c) To produce energy in the cell d) To absorb carbon dioxide Answer: b) To carry oxygen from the lungs to tissues 47. The primary consequence of smoking on the respiratory system is a) Destroyed cilia on the upper respiratory tract b) Enhanced oxygen absorption c) Decreased lung capacity d) Reduced risk of lung infections Answer: a) Destroyed cilia on the upper respiratory tract 48. The respiratory pigment is found in humans is a) Myoglobin b) Haemoglobin c) Chlorophyll d) Cytochrome Answer: b) Haemoglobin 49. The reason for the faster rate of breathing in aquatic organisms compared to terrestrial organisms is a) Higher oxygen content in water b) Lower oxygen content in water c) Larger surface area of respiratory organs d) Presence of gills Answer: b) Lower oxygen content in water 50. What happens during the breathing cycle to ensure sufficient gas exchange in the lungs? a) The lungs completely empty with each breath b) The diaphragm does not move c) Air is only inhaled, not exhaled d) The lungs always contain a residual volume of air Answer: d) The lungs always contain a residual volume of air TRANSPORTATION 51. The process of movement of water and other molecules to the concerned parts of the organism is called a) Photosynthesis b) Transpiration c) Transportation d) Respiration Answer: c) Transportation 52. Blood is a fluid a) Connective tissue b) Muscle tissue c) Epithelial tissue d) Fibrous tissue Answer: a) Connective tissue 53. Main function of plasma in the blood is a) To transport oxygen only b) To transport food, O2, CO2, and nitrogenous wastes c) To produce red blood cells d) To regulate body temperature Answer: b) To transport food, O2, CO2, and nitrogenous wastes 54. What is the normal level of haemoglobin in adult men? a) 12 to 15 g/100 ml b) 11 to 16 g/100 ml c) 14 to 17 g/100 ml d) 10.4 to 16.4 g/100 ml Answer: c) 14 to 17 g/100 ml 55. Which chamber of the heart receives oxygen-rich (oxygenated) blood from pulmonary veins? a) Left atrium b) Right atrium c) Right ventricle d) Left ventricle Answer: a) Left atrium 56. Ventricles have thicker muscular walls because a) they receive blood from the lungs b) they need to prevent the backflow of blood c) they pump blood into various organs d) they only pump blood to the lungs Answer: c) they pump blood into various organs 57. What instrument is used to measure blood pressure? a) Stethoscope b) Thermometer c) Sphygmomanometer d) Barometer Answer: c) Sphygmomanometer 58. What is the systolic pressure in the artery during ventricular systole (contraction)? a) About 80 mm Hg b) About 70 mm Hg c) About 90 mm Hg d) About 120 mm Hg Answer: d) About 120 mm Hg 59. What do veins have to ensure blood flows only in one direction? a) Thick elastic walls b) Valves c) High pressure d) Muscular walls Answer: b) Valves 60. What is the smallest type of blood vessel, where exchange of materials between blood and surrounding cells occurs? a) Arteries b) Veins c) Capillaries d) Arterioles Answer: c) Capillaries