🌿 Nutrition in Plants and Humans – Practice Questions Posted by By admin February 28, 2026 🌿 Nutrition in Plants and Humans – Practice Questions 🌿 Nutrition in Plants and Humans – Practice Questions 1 / 165 1. What is necessary for autotrophic nutrition? (a) Chlorophyll (b) H₂O and CO₂ (c) Sunlight (d) All of these 🧠 Explanation: Autotrophic organisms like plants require chlorophyll, water, carbon dioxide, and sunlight to perform photosynthesis. 🧠 Explanation: Autotrophic organisms like plants require chlorophyll, water, carbon dioxide, and sunlight to perform photosynthesis. 2 / 165 2. Consider the following statements: 1. In photosynthesis, simple inorganic molecules form complex organic molecules. 2. In plants, the inorganic molecules absorbed by roots are transformed into organic molecules through photosynthesis. Which of the above is/are correct? (a) Only 1 (b) Only 2 (c) Both 1 and 2 (d) Neither 1 nor 2 🧠 Explanation: Photosynthesis converts inorganic raw materials (CO₂ and H₂O) into organic compounds like glucose. 🧠 Explanation: Photosynthesis converts inorganic raw materials (CO₂ and H₂O) into organic compounds like glucose. 3 / 165 3. In parasitic and saprophytic nutrition, which life form absorbs food in living organisms or dead organisms? (a) Fungus (b) Amoeba (c) Algae (d) None of these 🧠 Explanation: Fungi are saprotrophs or parasites—they absorb nutrients from dead matter or host organisms. 🧠 Explanation: Fungi are saprotrophs or parasites—they absorb nutrients from dead matter or host organisms. 4 / 165 4. Which animal does not show a holozoic mode of nutrition? (a) Paramecium (b) Amoeba (c) Hydra (d) Fungus 🧠 Explanation: Fungus uses saprophytic nutrition, not holozoic, which involves ingestion and digestion inside the body. 🧠 Explanation: Fungus uses saprophytic nutrition, not holozoic, which involves ingestion and digestion inside the body. 5 / 165 5. Consider the following statements: 1. In green plants, photosynthesis is a type of autotrophic nutrition. 2. All green plants are autotrophs. Which is/are correct? (a) Only 1 (b) Only 2 (c) Both 1 and 2 (d) Neither 1 nor 2 🧠 Explanation: Green plants perform photosynthesis and are autotrophs, making their own food. 🧠 Explanation: Green plants perform photosynthesis and are autotrophs, making their own food. 6 / 165 6. Which is included under types of heterotrophic nutrition? (a) Saprotrophic (b) Parasitic (c) Holozoic (d) All of these Heterotrophic nutrition includes: Holozoic (e.g., humans) Parasitic (e.g., tapeworm) Saprotrophic (e.g., fungi) Heterotrophic nutrition includes: Holozoic (e.g., humans) Parasitic (e.g., tapeworm) Saprotrophic (e.g., fungi) 7 / 165 7. Which of the following is a parasite? (a) Mushroom (b) Hydra (c) Amoeba (d) Lice 🧠 Explanation: Lice are ectoparasites, feeding on blood from the host (humans/animals). 🧠 Explanation: Lice are ectoparasites, feeding on blood from the host (humans/animals). 8 / 165 8. Which of the following is NOT a correct equation for photosynthesis? a) CO₂ + H₂O → CH₂O + O₂ (b) 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂ (c) C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O (d) 6CO₂ + 12H₂O → C₆H₁₂O₆ + 6O₂ + 6H₂O 🧠 Explanation: This is the equation for respiration, not photosynthesis 🧠 Explanation: This is the equation for respiration, not photosynthesis 9 / 165 9. Consider the following statements related to photosynthesis: 1. Light energy is converted into chemical energy during photosynthesis. 2. Photosynthesis is an anabolic reaction. Which is/are correct? (a) Only 1 (b) Only 2 (c) Both 1 and 2 (d) Neither 1 nor 2 🧠 Explanation: Photosynthesis converts light into glucose (chemical energy) and is an anabolic (constructive) process 🧠 Explanation: Photosynthesis converts light into glucose (chemical energy) and is an anabolic (constructive) process 10 / 165 10. What is the process of converting light energy into chemical energy in photosynthesis called? (a) Photolysis (b) Photoactivation (c) Photophosphorylation (d) Carbon fixation 🧠 Explanation: Photophosphorylation refers to ATP formation using light energy during the light reaction of photosynthesis. 🧠 Explanation: Photophosphorylation refers to ATP formation using light energy during the light reaction of photosynthesis. 11 / 165 11. Which area of the leaf absorbs the maximum sunlight during photosynthesis? (a) Vein (b) Midrib (c) Upper surface (d) Lower surface 🧠 Explanation: The upper surface of the leaf has more chlorophyll and is directly exposed to sunlight. 🧠 Explanation: The upper surface of the leaf has more chlorophyll and is directly exposed to sunlight. 12 / 165 12. What percentage of total solar energy is used by plants during photosynthesis? (a) 1–2% (b) 10% (c) 50% (d) 100% 🧠 Explanation: Only about 1–2% of solar energy is actually captured by plants in photosynthesis. 🧠 Explanation: Only about 1–2% of solar energy is actually captured by plants in photosynthesis. 13 / 165 13. Which of the following statements are true? 1. Sunlight is necessary for photosynthesis. 2. Artificial light cannot support photosynthesis. (a) Only 1 (b) Only 2 (c) Both 1 and 2 (d) Neither 1 nor 2 🧠 Explanation: Sunlight is essential, but photosynthesis can also occur under artificial light, so statement 2 is incorrect. 🧠 Explanation: Sunlight is essential, but photosynthesis can also occur under artificial light, so statement 2 is incorrect. 14 / 165 15. Which of the following is essential for photosynthesis? (a) Oxygen is produced during photosynthesis (b) ATP is formed in photosynthesis (c) Light energy splits water into H and O (d) Glucose is the final product 🧠 Explanation: This is the core of the light reaction of photosynthesis. 🧠 Explanation: This is the core of the light reaction of photosynthesis. 15 / 165 14. Which of the following steps is NOT involved in photosynthesis? (a) Absorption of light (b) Conversion of light energy to chemical energy (c) Splitting of water molecules (d) Conversion of sugar to protein 🧠 Explanation: This is part of metabolism after photosynthesis, not part of the process itself. 🧠 Explanation: This is part of metabolism after photosynthesis, not part of the process itself. 16 / 165 16. What happens to the oxygen formed during photosynthesis? (a) Used in CO₂ fixation (b) Released (c) Used in respiration (d) Absorbed in thylakoids 🧠 Explanation: Oxygen is released as a by-product of photolysis of water. 🧠 Explanation: Oxygen is released as a by-product of photolysis of water. 17 / 165 17. Which is the limiting factor in photosynthesis under natural conditions? (a) CO₂ (b) Light (c) Water (d) Chlorophyll 🧠 Explanation: In nature, carbon dioxide concentration is often the limiting factor. 🧠 Explanation: In nature, carbon dioxide concentration is often the limiting factor. 18 / 165 18. Which organism produces the highest amount of oxygen on Earth? (a) Terrestrial plants (b) Algae (c) Trees (d) Soil bacteria 🧠 Explanation: Marine algae and phytoplankton are responsible for producing over 50% of Earth's oxygen. 🧠 Explanation: Marine algae and phytoplankton are responsible for producing over 50% of Earth's oxygen. 19 / 165 19. Which part of the plant shows maximum photosynthetic activity? (a) Root (b) Leaf (c) Stem (d) Bark 🧠 Explanation: Leaves, especially palisade mesophyll cells, contain the most chloroplasts. 🧠 Explanation: Leaves, especially palisade mesophyll cells, contain the most chloroplasts. 20 / 165 20. In which part of the leaf are guard cells and stomata found? (a) Root (b) Stem (c) Upper epidermis (d) Lower epidermis 🧠 Explanation: Most stomata are located on the lower surface to minimize water loss. 🧠 Explanation: Most stomata are located on the lower surface to minimize water loss. 21 / 165 21. How is the oxygen released in photosynthesis monitored? (a) Through sensors (b) By measuring bubble release (c) By weighing (d) By dry weight ✅ Answer: (b) By measuring bubble release ✅ Answer: (b) By measuring bubble release 22 / 165 22. When does the light reaction of photosynthesis occur? (a) Only during day (b) Only during night (c) During day and night (d) Daylight when NADPH₂ is available 🧠 Explanation: Light reaction only happens when sunlight is available. 🧠 Explanation: Light reaction only happens when sunlight is available. 23 / 165 23. In photosynthesis, O₂ is produced from: (a) CO₂ (b) Water (c) Both CO₂ and water (d) None 🧠 Explanation: Oxygen is released from photolysis of water molecules. 🧠 Explanation: Oxygen is released from photolysis of water molecules. 24 / 165 24. The process of nutrition in fungi is called: (a) Saprotrophic (b) Photosynthesis (c) Parasitism (d) None of these 🧠 Explanation: Fungi feed on dead organic matter via external digestion. 🧠 Explanation: Fungi feed on dead organic matter via external digestion. 25 / 165 25. During photosynthesis, in which part of the chloroplast is glucose formed? (a) Grana (b) Stroma (c) Thylakoid membrane (d) Outer membrane 🧠 Explanation: The Calvin cycle, where glucose is synthesized, occurs in the stroma. 🧠 Explanation: The Calvin cycle, where glucose is synthesized, occurs in the stroma. 26 / 165 26. Consider the statements: 1. The light-dependent reaction is also called photolysis. 2. Chloroplasts are the site of photosynthesis. Which is/are true? (a) Only 1 (b) Only 2 (c) Both 1 and 2 (d) Neither 1 nor 2 🧠 Explanation: Both are scientifically valid statements. 🧠 Explanation: Both are scientifically valid statements. 27 / 165 27. Which is NOT a type of autotrophic nutrition? (a) Chemoautotrophic (b) Heterotrophic (c) Photoautotrophic (d) None of these 🧠 Explanation: Heterotrophs depend on others for food, unlike autotrophs. 🧠 Explanation: Heterotrophs depend on others for food, unlike autotrophs. 28 / 165 28. Consider the following statements: 1. Red light is most effective for photosynthesis. 2. Blue light is more effective than green. Which is/are correct? (a) Only 1 (b) Only 2 (c) Both 1 and 2 (d) Neither 1 nor 2 🧠 Explanation: Red and blue are absorbed more efficiently by chlorophyll than green. 🧠 Explanation: Red and blue are absorbed more efficiently by chlorophyll than green. 29 / 165 29. Which gas is used in photosynthesis? (a) Oxygen (b) CO₂ (c) Nitrogen (d) Hydrogen 🧠 Explanation: Carbon dioxide is the main raw material in photosynthesis. 🧠 Explanation: Carbon dioxide is the main raw material in photosynthesis. 30 / 165 30. How does CO₂ enter the leaf? (a) Through roots (b) Through stomata (c) Via xylem (d) Through phloem 🧠 Explanation: Stomata are tiny pores for gas exchange in leaves. 🧠 Explanation: Stomata are tiny pores for gas exchange in leaves. 31 / 165 31. Which of the following is essential for the formation of proteins? (a) Chlorophyll (b) Mitochondria (c) DNA (d) Nitrogen 🧠 Explanation: Nitrogen is needed to make amino acids and hence proteins. 🧠 Explanation: Nitrogen is needed to make amino acids and hence proteins. 32 / 165 32. Assertion (A): A plant kept in the dark for several days shows pale-yellow leaves. Reason (R): Lack of sunlight stops chlorophyll formation. (a) A and R both are true and R explains A (b) A and R both are true but R doesn’t explain A (c) A is true, R is false (d) A is false, R is true 🧠 Explanation: Chlorophyll needs light for synthesis; without it, leaves turn yellow (chlorosis). ✅ Answer: (a) A and R both are true and R explains A 🧠 Explanation: Chlorophyll needs light for synthesis; without it, leaves turn yellow (chlorosis). 33 / 165 33. Which of the following is NOT a feature of photosynthesis? (a) Capturing light energy from sunlight (b) Converting light energy to chemical energy (c) Using carbon dioxide and water to form glucose (d) Releasing oxygen and carbon dioxide simultaneously 🧠 Explanation: Oxygen is released in photosynthesis, but carbon dioxide is consumed, not released. 🧠 Explanation: Oxygen is released in photosynthesis, but carbon dioxide is consumed, not released. 34 / 165 35. What is the final product of the light reaction in photosynthesis? (a) Hydrogen (b) Oxygen (c) ATP and NADPH (d) All of these 🧠 Explanation: Light reaction produces Oxygen, ATP, and NADPH. 🧠 Explanation: Light reaction produces Oxygen, ATP, and NADPH. 35 / 165 34. Which part of the leaf is called the "food factory"? (a) Leaf (b) Root (c) Stem (d) Branch 🧠 Explanation: Leaves are the primary sites of photosynthesis, making food for the plant. 🧠 Explanation: Leaves are the primary sites of photosynthesis, making food for the plant. 36 / 165 36. Consider the statements— 1. Photosynthesis is more efficient between 30°C–35°C. 2. Water loss due to transpiration affects photosynthesis. Which is/are true? (a) Only 1 (b) Only 2 (c) Both 1 and 2 (d) Neither 1 nor 2 🧠 Explanation: Moderate temperature enhances enzyme function; water loss reduces turgor pressure and photosynthesis. 🧠 Explanation: Moderate temperature enhances enzyme function; water loss reduces turgor pressure and photosynthesis. 37 / 165 37. Which pigments help in trapping light energy in photosynthesis? (a) Chlorophyll A (b) Chlorophyll B (c) Xanthophyll (d) Carotenoids (c) 1, 2, and 4 🧠 Explanation: All except Xanthophyll directly absorb light. Chlorophyll A is primary; B and carotenoids are accessory 🧠 Explanation: All except Xanthophyll directly absorb light. Chlorophyll A is primary; B and carotenoids are accessory 38 / 165 38. Who gave the complete explanation of light and dark reactions in photosynthesis? (a) Robert Hooke (b) Joseph Priestley (c) Julius von Sachs (d) Robert Brown 🧠 Explanation: Julius von Sachs gave major insight into photosynthetic processes, including starch formation. 🧠 Explanation: Julius von Sachs gave major insight into photosynthetic processes, including starch formation. 39 / 165 39. The first stable product formed in photosynthesis is— (a) Formed by fixation of carbon dioxide in stroma (b) Formed in thylakoids by light reaction (c) Released with oxygen as a byproduct (d) NADPH 🧠 Explanation: 3-PGA (3-Phosphoglycerate) is the first stable product, formed in the stroma during the Calvin cycle. 🧠 Explanation: 3-PGA (3-Phosphoglycerate) is the first stable product, formed in the stroma during the Calvin cycle. 40 / 165 40. Which gas is used during dark reaction of photosynthesis? (a) Oxygen (b) Sunlight (c) CO₂ (d) None of these 🧠 Explanation: The Calvin cycle (dark reaction) uses carbon dioxide to form glucose. 🧠 Explanation: The Calvin cycle (dark reaction) uses carbon dioxide to form glucose. 41 / 165 41. Who was awarded the Nobel Prize for work on photosynthesis? (a) Jan Ingenhousz (b) Peter Mitchell (c) Melvin Calvin (d) Robert Hooke 🧠 Explanation: Melvin Calvin received the Nobel Prize for discovering the Calvin Cycle. 🧠 Explanation: Melvin Calvin received the Nobel Prize for discovering the Calvin Cycle. 42 / 165 42. Which of the following is NOT used in the light reaction of photosynthesis? (a) Light (b) Enzymes (c) Chlorophyll (d) CO₂ 🧠 Explanation: CO₂ is used in the dark reaction, not the light reaction. 🧠 Explanation: CO₂ is used in the dark reaction, not the light reaction. 43 / 165 43. What is the first step of photosynthesis? (a) Formation of ATP (b) Splitting of water molecules (c) Conversion of CO₂ to glucose (d) Oxygen release 🧠 Explanation: Photolysis (splitting of water) is the initial step in the light-dependent reaction. 🧠 Explanation: Photolysis (splitting of water) is the initial step in the light-dependent reaction. 44 / 165 44. Which process plays the main role in oxygen evolution? (a) Water absorption (b) Light absorption (c) CO₂ absorption (d) None 🧠 Explanation: Light energy is required to split water and release oxygen. 🧠 Explanation: Light energy is required to split water and release oxygen. 45 / 165 45. Which enzyme removes hydrogen from water and fixes it in NADPH₂? (a) Peroxidase (b) Carboxylase (c) Reductase (d) ATP synthase 🧠 Explanation: Reductase enzymes help in the transfer of hydrogen to NADP⁺, forming NADPH₂. 🧠 Explanation: Reductase enzymes help in the transfer of hydrogen to NADP⁺, forming NADPH₂. 46 / 165 46. In which cell organelle does photosynthesis occur? (a) Mitochondria (b) Chloroplast (c) Ribosome (d) Lysosome 🧠 Explanation: Chloroplasts contain chlorophyll and are the sites of photosynthesis. 🧠 Explanation: Chloroplasts contain chlorophyll and are the sites of photosynthesis. 47 / 165 47. What is the role of xylem in photosynthesis? (a) CO₂ absorption (b) Light absorption (c) Water transport (d) No role 🧠 Explanation: Xylem transports water from roots to leaves, essential for photosynthesis. 🧠 Explanation: Xylem transports water from roots to leaves, essential for photosynthesis. 48 / 165 48. What is the final product of photosynthesis? (a) Glucose (b) Water (c) Oxygen (d) ATP 🧠 Explanation: The Calvin cycle results in the formation of glucose. 🧠 Explanation: The Calvin cycle results in the formation of glucose. 49 / 165 49. Where does maximum photosynthesis occur in plants? (a) In red and blue light (b) In red and green light (c) In blue and yellow light (d) In yellow and green light 🧠 Explanation: Chlorophyll absorbs red and blue wavelengths most efficiently. 🧠 Explanation: Chlorophyll absorbs red and blue wavelengths most efficiently. 50 / 165 50. Which element is essential for chlorophyll synthesis? (a) Magnesium (b) Iron (c) Phosphorus (d) Zinc 🧠 Explanation: Magnesium (Mg²⁺) is a central atom in the chlorophyll molecule. 🧠 Explanation: Magnesium (Mg²⁺) is a central atom in the chlorophyll molecule. 51 / 165 51. What is the first step of the photosynthesis process? (a) Activation of chlorophyll by sunlight (b) Excitation of electrons in chlorophyll by sunlight (c) Release of oxygen from water (d) Formation of carbohydrates � Explanation: The first step is chlorophyll activation by sunlight, initiating light reactions. � Explanation: The first step is chlorophyll activation by sunlight, initiating light reactions. 52 / 165 52. In which light is the rate of photosynthesis highest? (a) In every kind of light (b) In blue light (c) In green light (d) In red light 🧠 Explanation: Red light is most efficient for photosynthesis due to maximum chlorophyll absorption. 🧠 Explanation: Red light is most efficient for photosynthesis due to maximum chlorophyll absorption. 53 / 165 53. In which light is the rate of photosynthesis lowest? (a) In red light (b) In green light (c) In blue light (d) In all colors equally 🧠 Explanation: Green light is mostly reflected by chlorophyll; hence least photosynthesis occurs. 🧠 Explanation: Green light is mostly reflected by chlorophyll; hence least photosynthesis occurs. 54 / 165 54. What is photosynthesis? (a) A physical process (b) Occurs in air and light (c) A chemical change (d) Both (b) and (c) 🧠 Explanation: It is a chemical change that takes place in presence of light and air (CO₂). 🧠 Explanation: It is a chemical change that takes place in presence of light and air (CO₂). 55 / 165 55. Consider the following— 1. Photosynthesis does not occur in absence of sunlight or in darkness. 2. Complete process of photosynthesis requires sunlight. Which is/are correct? (a) Only 1 (a) Only 2 (c) Both 1 and 2 🧠 Explanation: Both light and dark reactions are dependent directly or indirectly on sunlight. 🧠 Explanation: Both light and dark reactions are dependent directly or indirectly on sunlight. 56 / 165 56. Which part of green plants carries out photosynthesis? (a) Chlorophyll (b) Chloroplast (c) Chlorophyll-containing cell (d) None of these 🧠 Explanation: Photosynthesis takes place in the chloroplasts, which contain chlorophyll. 🧠 Explanation: Photosynthesis takes place in the chloroplasts, which contain chlorophyll. 57 / 165 57. Oxygen is used in— (a) As a byproduct of photosynthesis (b) In breathing process (c) In both (d) None of these 🧠 Explanation: Oxygen is produced during photosynthesis and used in respiration. 🧠 Explanation: Oxygen is produced during photosynthesis and used in respiration. 58 / 165 58. Consider the following— 1. In photosynthesis, carbohydrate and oxygen gas are produced. 2. Photosynthesis occurs in all green parts of a plant. Which is/are correct? (a) Only 1 (a) Only 2 (c) Both 1 and 2 🧠 Explanation: Both statements are true. Carbohydrates (like glucose) and oxygen are the end products. 🧠 Explanation: Both statements are true. Carbohydrates (like glucose) and oxygen are the end products. 59 / 165 59. Which of the following is true for artificial light? (a) Can promote leaf fall (b) Can stimulate photosynthesis (c) Can’t help photosynthesis (d) May stop photosynthesis 🧠 Explanation: Artificial light (like LED or fluorescent) can stimulate photosynthesis if it contains appropriate wavelengths. 🧠 Explanation: Artificial light (like LED or fluorescent) can stimulate photosynthesis if it contains appropriate wavelengths. 60 / 165 60. Why do some animals eat nightshade plants? (a) Due to lack of light they can’t do photosynthesis and depend on others (b) Due to adaptation, they obtain nutrition from others (c) Both A and B (d) Neither A nor B 🧠 Explanation: Parasites like Cuscuta (dodder) lack chlorophyll and depend on hosts. 🧠 Explanation: Parasites like Cuscuta (dodder) lack chlorophyll and depend on hosts. 61 / 165 61. What are autotrophs? (a) Animals (b) Plants (c) Producers (d) None of these 🧠 Explanation: Autotrophs (like green plants) prepare their own food — hence they are producers. 🧠 Explanation: Autotrophs (like green plants) prepare their own food — hence they are producers. 62 / 165 62. Where is parasitic nutrition found? (a) In mushrooms (b) In mango and neem (c) In tape worms (d) In lotus 🧠 Explanation: Tape worms are parasites that derive nutrition from host organisms. 🧠 Explanation: Tape worms are parasites that derive nutrition from host organisms. 63 / 165 63. How many types of teeth are found in a human adult’s upper and lower jaws? Four Four 🧠 Explanation: Humans have four types of teeth — incisors, canines, premolars, molars. 🧠 Explanation: Humans have four types of teeth — incisors, canines, premolars, molars. 64 / 165 64. Which teeth help in tearing food? (a) Incisors (b) Canines (c) Premolars (d) Molars 🧠 Explanation: Canines are sharp-pointed teeth designed to tear food, especially meat. 🧠 Explanation: Canines are sharp-pointed teeth designed to tear food, especially meat. 65 / 165 65. Which teeth are used for chewing and grinding? (a) Incisors (b) Molars (c) Canines (d) Premolars and molars 🧠 Explanation: Premolars and molars have broad surfaces ideal for grinding food. 🧠 Explanation: Premolars and molars have broad surfaces ideal for grinding food. 66 / 165 66. Consider the following— 1. Digestion begins in the mouth. 2. Saliva breaks down carbohydrates. Which is/are correct? (a) Only 1 (a) Only 2 (c) Both 1 and 2 🧠 Explanation: Saliva contains amylase, which breaks down starch, starting digestion in the mouth. 🧠 Explanation: Saliva contains amylase, which breaks down starch, starting digestion in the mouth. 67 / 165 67. Which of the following is not true? (a) Tongue detects taste (b) Tongue moves food during chewing (c) Tongue mixes saliva (d) Tongue digests starch 🧠 Explanation: Tongue helps move food and detect taste, but doesn’t digest food. 🧠 Explanation: Tongue helps move food and detect taste, but doesn’t digest food. 68 / 165 68. Which part of the tooth protects dentine and remains shiny? (a) Pulp (b) Enamel (c) Cement (d) None of these 🧠 Explanation: Enamel is the outermost, shiny, and hardest layer of the tooth protecting dentine. 🧠 Explanation: Enamel is the outermost, shiny, and hardest layer of the tooth protecting dentine. 69 / 165 69. How many types of teeth are found in the human mouth? (a) 1 (b) 2 (c) 3 (d) 4 🧠 Explanation: Humans have 4 types of teeth — incisors, canines, premolars, and molars. 🧠 Explanation: Humans have 4 types of teeth — incisors, canines, premolars, and molars. 70 / 165 70. Which type of teeth are the least in number in the human mouth? (a) Incisors (b) Canines (c) Premolars (d) Molars 🧠 Explanation: Humans have 4 canines (2 in each jaw), which are fewer than other types. 🧠 Explanation: Humans have 4 canines (2 in each jaw), which are fewer than other types. 71 / 165 71. Which part prepares the hard part of the teeth? (a) Oral cavity (b) Saliva (c) Enamel (d) None of these 🧠 Explanation: The enamel is the hardest substance in the human body, forming the outermost part of the tooth. 🧠 Explanation: The enamel is the hardest substance in the human body, forming the outermost part of the tooth. 72 / 165 72. What is the outer covering of the teeth made of calcium phosphate called? (a) Enamel (b) Dentine (c) Cement (d) Pulp 🧠 Explanation: Enamel is rich in calcium phosphate and covers the outer part of the tooth. 🧠 Explanation: Enamel is rich in calcium phosphate and covers the outer part of the tooth. 73 / 165 73. Consider the following— 1. The outer covering of the tooth is enamel. 2. Human body contains calcium. 3. The calcium in the mouth helps form enamel. Which of the above are correct? (d) All 1, 2, and 3 (d) All 1, 2, and 3 74 / 165 74. Which part of the tongue detects sweet taste? (a) Tip (b) Sides (c) Middle (d) All of these 🧠 Explanation: The tip of the tongue is sensitive to sweet tastes. 🧠 Explanation: The tip of the tongue is sensitive to sweet tastes. 75 / 165 76. What happens after food enters the mouth? (a) Grinding (b) Tasting (c) Chewing (d) Digestion 🧠 Explanation: Food is chewed (masticated) by teeth after entering the mouth. 🧠 Explanation: Food is chewed (masticated) by teeth after entering the mouth. 76 / 165 75. Which part of the tongue detects bitter taste? (a) Tip (b) Sides (c) Back (d) Entire tongue 🧠 Explanation: The back part of the tongue detects bitter tastes. 🧠 Explanation: The back part of the tongue detects bitter tastes. 77 / 165 77. Sometimes food gets stuck in the windpipe while talking or laughing while eating. What is the reason? ✅ Answer: (c) Entry into the esophagus is blocked due to laughing or talking. 🧠 Explanation: The epiglottis may fail to cover the windpipe, causing food to enter the trachea. 🧠 Explanation: The epiglottis may fail to cover the windpipe, causing food to enter the trachea. 78 / 165 78. Where does digestion start? (a) In the mouth (b) In the small intestine (c) In the large intestine (d) In the stomach 🧠 Explanation: Digestion begins in the mouth with the help of salivary enzymes. 🧠 Explanation: Digestion begins in the mouth with the help of salivary enzymes. 79 / 165 79. What is the main function of the stomach? (a) Storage of carbohydrates (b) Storage of fats (c) Protein digestion (d) None of these 🧠 Explanation: Proteins are digested in the stomach by the enzyme pepsin. 🧠 Explanation: Proteins are digested in the stomach by the enzyme pepsin. 80 / 165 80. Pepsin enzyme remains active in— (a) Acidic medium (b) Basic medium (c) Neutral medium (d) Alkaline medium 🧠 Explanation: Pepsin requires an acidic pH to function, provided by HCl in the stomach. 🧠 Explanation: Pepsin requires an acidic pH to function, provided by HCl in the stomach. 81 / 165 81. Which acid is secreted in the stomach to activate pepsin? (a) Hydrochloric acid (b) Pepsin enzyme (c) Lactic acid (d) Uric acid 🧠 Explanation: HCl activates pepsinogen to pepsin and maintains the acidic pH. 🧠 Explanation: HCl activates pepsinogen to pepsin and maintains the acidic pH. 82 / 165 82. Why does stomach acid not harm stomach cells? (a) Stomach has a protective mucous lining (b) Stomach acid is very weak (c) Acid is neutralized by saliva (d) Acid is present in small quantity 🧠 Explanation: The mucus lining of the stomach protects it from corrosive effects of HCl. 🧠 Explanation: The mucus lining of the stomach protects it from corrosive effects of HCl. 83 / 165 83. Chewing helps in— (a) Mixing protein with saliva (b) Breaking food into small pieces (c) Moistening the food (d) All of these 🧠 Explanation: Chewing breaks, moistens, and mixes food with saliva for digestion. 🧠 Explanation: Chewing breaks, moistens, and mixes food with saliva for digestion. 84 / 165 84. Which digestion begins in the stomach? (a) Starch (b) Protein (c) Fat (d) Fiber 🧠 Explanation: Protein digestion begins in the stomach with pepsin. 🧠 Explanation: Protein digestion begins in the stomach with pepsin. 85 / 165 85. Pepsin is a type of— (a) Vitamin (b) Enzyme (c) Acid (d) Salt 🧠 Explanation: Pepsin is a protein-digesting enzyme secreted in the stomach. 🧠 Explanation: Pepsin is a protein-digesting enzyme secreted in the stomach. 86 / 165 86. Where does protein digestion begin? (a) Mouth (b) Stomach (c) Intestine (d) Rectum 🧠 Explanation: Proteins begin to digest in the stomach. 🧠 Explanation: Proteins begin to digest in the stomach. 87 / 165 87. For bitter taste, which part of the tongue is responsible? (a) Tip (b) Sides (c) Middle (d) Back 🧠 Explanation: The back of the tongue is sensitive to bitter taste. 🧠 Explanation: The back of the tongue is sensitive to bitter taste. 88 / 165 88. What is the function of amylase enzyme? (a) Breaks down starch (b) Digests fat (c) Digests proteins (d) Digests fiber 🧠 Explanation: Amylase (in saliva) breaks starch (complex carbs) into maltose. 🧠 Explanation: Amylase (in saliva) breaks starch (complex carbs) into maltose. 89 / 165 89. In which part of the alimentary canal is the food churned into a semiliquid? (a) Mouth (b) Small intestine (c) Large intestine (d) Stomach 🧠 Explanation: Churning of food into chyme occurs in the stomach. 🧠 Explanation: Churning of food into chyme occurs in the stomach. 90 / 165 90. The tongue is connected to the floor of the mouth by which structure? (b) Frenulum 🧠 Explanation: The frenulum is a thin fold of tissue that anchors the tongue to the bottom of the mouth. 91 / 165 91. Which specific enzyme helps in digesting milk protein? (a) Pepsin (b) Trypsin (c) Rennin (d) All of these 🧠 Explanation: Rennin (also called chymosin) helps in the digestion of casein, the main milk protein, especially in infants. 🧠 Explanation: Rennin (also called chymosin) helps in the digestion of casein, the main milk protein, especially in infants. 92 / 165 92. Which of the following is true? (a) In the stomach of an infant, protein is digested, and a curd-like fluid is formed. (b) The stomach is the main site for protein digestion. (c) Along with protein digestion, food is also stored in the stomach. (d) All of the above 🧠 Explanation: All the options accurately describe the role of the stomach in digestion and storage, especially in infants. 🧠 Explanation: All the options accurately describe the role of the stomach in digestion and storage, especially in infants. 93 / 165 93. What is the shape of the stomach? (a) Round (b) Pear-shaped (c) Bag-like (d) Tubular 🧠 Explanation: The stomach is a J-shaped (bag-like) organ that stores and churns food. 🧠 Explanation: The stomach is a J-shaped (bag-like) organ that stores and churns food. 94 / 165 94. Which of the following is not an enzyme of the stomach? (a) Amylase (b) Pepsin (c) Rennin (d) Trypsin 🧠 Explanation: Trypsin is secreted by the pancreas, not the stomach. 🧠 Explanation: Trypsin is secreted by the pancreas, not the stomach. 95 / 165 95. Which of the following is not a function of hydrochloric acid (HCl) in the stomach? (a) Kills bacteria present with food (b) Activates pepsinogen to pepsin (c) Helps in breaking down of food (d) Absorbs nutrients 🧠 Explanation: HCl aids digestion and sterilization but does not absorb nutrients. 🧠 Explanation: HCl aids digestion and sterilization but does not absorb nutrients. 96 / 165 96. Which of the following is incorrect about gastric juice? (a) It activates digestive enzymes in the stomach (b) It mixes food in the stomach with enzymes (c) It digests food and absorbs vitamins (d) It contains HCl and enzymes like pepsin 🧠 Explanation: Stomach digests but does not absorb vitamins (absorption mainly happens in the small intestine). 🧠 Explanation: Stomach digests but does not absorb vitamins (absorption mainly happens in the small intestine). 97 / 165 97. How many sets of teeth are developed in a human’s lifetime? (a) 4 (b) 2 (c) 20 (d) 28 🧠 Explanation: Humans develop 2 sets of teeth: milk (deciduous) and permanent teeth. 🧠 Explanation: Humans develop 2 sets of teeth: milk (deciduous) and permanent teeth. 98 / 165 98. Enzymes are important in the body because— (a) They accelerate chemical reactions (b) They provide energy (c) They digest proteins only (d) They produce heat 🧠 Explanation: Enzymes act as biological catalysts to speed up reactions. 🧠 Explanation: Enzymes act as biological catalysts to speed up reactions. 99 / 165 99. Which is the most essential nutrient for digesting food in the stomach? (a) Water (b) Pepsin (c) Bile (d) Food 🧠 Explanation: Pepsin is the main enzyme that digests proteins in the stomach. 🧠 Explanation: Pepsin is the main enzyme that digests proteins in the stomach. 100 / 165 100. Which enzyme digests milk protein? (a) Pepsin (b) Trypsin (c) Rennin (d) None 🧠 Explanation: Rennin helps in curdling and digestion of milk protein (casein). 🧠 Explanation: Rennin helps in curdling and digestion of milk protein (casein). 101 / 165 101. What is the total number of teeth in adult human dentition? (a) 16 (b) 18 (c) 25 (d) 32 🧠 Explanation: An adult has 32 permanent teeth (including wisdom teeth). 🧠 Explanation: An adult has 32 permanent teeth (including wisdom teeth). 102 / 165 102. What is the length of the human digestive tract? (a) 8–10 m (b) 6–10 cm (c) 2–6 m (d) 1–2 m 🧠 Explanation: The entire human digestive tract is approximately 8–10 meters long. 🧠 Explanation: The entire human digestive tract is approximately 8–10 meters long. 103 / 165 103. Which of the following is not a secretion of the stomach? (a) Hydrochloric acid (b) Gastric juice (c) Salivary amylase (d) Pepsin enzyme 🧠 Explanation: Salivary amylase is secreted by salivary glands, not the stomach. 🧠 Explanation: Salivary amylase is secreted by salivary glands, not the stomach. 104 / 165 104. Which of the following is not present in gastric juice? a) Pepsin enzyme (b) Hydrochloric acid (c) Rennin (d) Salivary amylase 🧠 Explanation: Salivary amylase acts in the mouth, not in the stomach. 🧠 Explanation: Salivary amylase acts in the mouth, not in the stomach. 105 / 165 105. Which part of the alimentary canal is involved in forming the bolus (chewed food ball)? (a) Mouth (b) Pharynx (c) Esophagus (d) Stomach 🧠 Explanation: Chewing and saliva in the mouth help form a bolus for swallowing. 🧠 Explanation: Chewing and saliva in the mouth help form a bolus for swallowing. 106 / 165 106. The acid in the stomach helps digestion by activating which enzyme, labeled ‘X’? (a) Salivary amylase (b) Pepsinogen (c) Pancreatic lipase (d) Bile juice 🧠 Explanation: HCl converts inactive pepsinogen into active pepsin enzyme. 🧠 Explanation: HCl converts inactive pepsinogen into active pepsin enzyme. 107 / 165 107. Which part of the cell is the site of energy production? (a) Smooth Endoplasmic Reticulum (b) Rough Endoplasmic Reticulum (c) Nucleus (d) Mitochondria 🧠 Explanation: The mitochondria are known as the "powerhouse of the cell." 🧠 Explanation: The mitochondria are known as the "powerhouse of the cell." 108 / 165 108. Which layer of the teeth is the hardest and helps in chewing and grinding? (a) Pulp (b) Dentine (c) Enamel (d) Cement 🧠 Explanation: Enamel is the hardest substance in the human body. 🧠 Explanation: Enamel is the hardest substance in the human body. 109 / 165 109. What causes the sour taste when stomach acid comes into contact with the tongue? (a) Hydrochloric acid (b) Salivary glands (c) Pepsin (d) Trypsin 🧠 Explanation: The sour taste is due to the presence of hydrochloric acid (HCl) in the stomach. 🧠 Explanation: The sour taste is due to the presence of hydrochloric acid (HCl) in the stomach. 110 / 165 110. In which part of the cell are nutrients related to vegetables stored? (a) Cytoplasmic matrix (b) Cytoplasmic reticulum (c) Vacuole (d) None 🧠 Explanation: Vacuoles store nutrients, water, and waste products in plant cells. 🧠 Explanation: Vacuoles store nutrients, water, and waste products in plant cells. 111 / 165 111. Select the correct statement: 1. Most digestion of food occurs in the stomach. 2. Food digested in the small intestine is absorbed. Which is/are correct? (a) Only 1 (b) Only 2 (c) Both (d) Neither 🧠 Explanation: The small intestine is the main site for digestion and absorption; the stomach initiates digestion but not most of it. 🧠 Explanation: The small intestine is the main site for digestion and absorption; the stomach initiates digestion but not most of it. 112 / 165 112. Improper eating can cause pain in which part of the alimentary canal? (a) Mouth (b) Stomach (c) Small intestine (d) Large intestine 🧠 Explanation: Indigestion and acidity due to improper food mostly affect the stomach. 🧠 Explanation: Indigestion and acidity due to improper food mostly affect the stomach. 113 / 165 113. Which is not a part of the large intestine? (a) Rectum (b) Colon (c) Small intestine (d) Anus 🧠 Explanation: The large intestine includes colon, rectum, and anus, but not the small intestine. 🧠 Explanation: The large intestine includes colon, rectum, and anus, but not the small intestine. 114 / 165 114. Which of the following is not part of the human large intestine? (a) Duodenum (b) Colon (c) Rectum (d) Anus 🧠 Explanation: The duodenum is the first part of the small intestine. 🧠 Explanation: The duodenum is the first part of the small intestine. 115 / 165 115. What is the longest organ of the human body? Small intestine Small intestine 🧠 Explanation: The small intestine is approximately 6 meters long — the longest internal organ. 🧠 Explanation: The small intestine is approximately 6 meters long — the longest internal organ. 116 / 165 116. Select the correct statement: 1. Blood plasma contains dissolved nutrients. 2. Nutrients from digested food are absorbed into blood capillaries. Which is/are correct? (a) Only 1 (a) Only 2 (c) Both 1 and 2 🧠 Explanation: Both statements are correct; nutrients are absorbed into blood capillaries and dissolved in plasma. 🧠 Explanation: Both statements are correct; nutrients are absorbed into blood capillaries and dissolved in plasma. 117 / 165 117. Digestion of fat is completed in— (a) Mouth (b) Stomach (c) Small intestine (d) All of the above 🧠 Explanation: Fat is digested mainly in the small intestine with help from bile and lipase enzymes. 🧠 Explanation: Fat is digested mainly in the small intestine with help from bile and lipase enzymes. 118 / 165 118. Which part of the alimentary canal is the longest? (a) Mouth (b) Stomach (c) Small intestine (d) Large intestine 🧠 Explanation: The small intestine is the longest digestive part (6 meters). 🧠 Explanation: The small intestine is the longest digestive part (6 meters). 119 / 165 119. Which part of the human digestive system performs the most digestion? (a) Large intestine (b) Small intestine (c) Stomach (d) Mouth 🧠 Explanation: Most digestion and all absorption occur in the small intestine. 🧠 Explanation: Most digestion and all absorption occur in the small intestine. 120 / 165 120. Where are most nutrients absorbed in the digestive tract? (a) Mouth (b) Large intestine (c) Small intestine (d) Stomach 🧠 Explanation: The small intestine is the primary site of nutrient absorption. 🧠 Explanation: The small intestine is the primary site of nutrient absorption. 121 / 165 121. Which is a carbohydrate-digesting enzyme? (a) Pepsin (b) Lipase (c) Nuclease (d) Amylase 🧠 Explanation: Amylase digests starch (a carbohydrate) into simpler sugars. 🧠 Explanation: Amylase digests starch (a carbohydrate) into simpler sugars. 122 / 165 122. Which is a fat-digesting enzyme? (a) Pepsin (b) Lipase (c) Trypsin (d) Maltase 🧠 Explanation: Lipase breaks down fats (lipids) into fatty acids and glycerol. 🧠 Explanation: Lipase breaks down fats (lipids) into fatty acids and glycerol. 123 / 165 123. Which of the following is NOT a protein-digesting enzyme? (a) Pepsin (b) Trypsin (c) Chymotrypsin (d) Amylase 🧠 Explanation: Amylase digests carbohydrates, not proteins. 🧠 Explanation: Amylase digests carbohydrates, not proteins. 124 / 165 124. Which mineral is found in high quantity in tooth enamel? (a) Copper (b) Iron (c) Calcium (d) Phosphorus 🧠 Explanation: Calcium phosphate is the main component of tooth enamel. 🧠 Explanation: Calcium phosphate is the main component of tooth enamel. 125 / 165 125. Iron is found in— (a) Bone marrow (b) Red blood cells (c) Muscles (d) Fat 🧠 Explanation: Iron is a component of hemoglobin, present in red blood cells. 🧠 Explanation: Iron is a component of hemoglobin, present in red blood cells. 126 / 165 126. In which part of the small intestine are nutrients absorbed? (a) Mouth (b) Stomach (c) Small intestine (d) Large intestine 🧠 Explanation: Absorption of digested nutrients takes place in the small intestine. 🧠 Explanation: Absorption of digested nutrients takes place in the small intestine. 127 / 165 127. Fats in the small intestine are digested with the help of which organ’s secretion? Liver (via bile juice) 🧠 Explanation: Bile from the liver emulsifies fat and helps lipase to digest it. 128 / 165 128. What is the main function of saliva? (a) Softens food and converts starch to sugar (b) Activates taste buds (c) Helps digestion in the stomach (d) None 🧠 Explanation: Saliva contains salivary amylase, which breaks down starch and softens food 🧠 Explanation: Saliva contains salivary amylase, which breaks down starch and softens food 129 / 165 129. What kind of proteins are formed from combinations of amino acids? (a) Casein (b) Albumin (c) Enzymes (d) Phospholipids 🧠 Explanation: Enzymes are functional proteins formed from amino acids. 🧠 Explanation: Enzymes are functional proteins formed from amino acids. 130 / 165 130. Which of the following is NOT a digestive juice? (a) Saliva (b) Gastric juice (c) Pancreatic juice (d) Blood 🧠 Explanation: Blood is not a digestive secretion. 🧠 Explanation: Blood is not a digestive secretion. 131 / 165 131. Select the correct statements: 1. Carbohydrates are digested by amylase. 2. Maltose is a disaccharide. 3. Glucose is a monosaccharide. 4. Proteins are digested in the stomach (a) 1, 2, 3 (a) 1, 2, 3, 4 (a) 1, 2 (a) 2, 3 🧠 Explanation: All are correct except digestion of proteins occurs partly in stomach, mostly in small intestine. 🧠 Explanation: All are correct except digestion of proteins occurs partly in stomach, mostly in small intestine. 132 / 165 132. Column (A): Which nutrient plays the most important role in fat digestion in humans? Bile 🧠 Explanation: Bile juice from the liver emulsifies fats, aiding their digestion. 133 / 165 133. Which organ identifies the special components in spoiled food? (a) Stomach (b) Intestine (c) Tongue (d) Saliva 🧠 Explanation: The tongue detects spoiled or harmful substances by sensing taste and bitterness. 🧠 Explanation: The tongue detects spoiled or harmful substances by sensing taste and bitterness. 134 / 165 134. Which part of food is used in the body as glycogen? (a) Large intestine (b) Small intestine (c) Glucose (d) Liver 🧠 Explanation: Glucose is converted to glycogen for storage in liver and muscles. 🧠 Explanation: Glucose is converted to glycogen for storage in liver and muscles. 135 / 165 135. In which organ is harmful ammonia converted into urea? (a) Stomach (b) Liver (c) Kidney (d) Small intestine 🧠 Explanation: The liver converts ammonia (toxic) to urea, which is excreted in urine. 🧠 Explanation: The liver converts ammonia (toxic) to urea, which is excreted in urine. 136 / 165 136. Select the correct statement: (a) Villi in small intestine increase surface area for absorption (b) Mouth secretes saliva with enzymes (c) Tongue helps to taste and mix food (d) All of these 🧠 Explanation: All are correct – each organ contributes to digestion and absorption. 🧠 Explanation: All are correct – each organ contributes to digestion and absorption. 137 / 165 137. What is the average daily protein requirement? (a) 1.5 grams (b) 100 grams (c) 140 grams (d) 60 grams 🧠 Explanation: An average adult needs about 60 grams of protein per day. 🧠 Explanation: An average adult needs about 60 grams of protein per day. 138 / 165 138. What does the liver do? (a) Regulates various chemical activities in the body (b) Metabolizes carbohydrates and detoxifies substances (c) Converts excess glucose to glycogen (d) All of the above 🧠 Explanation: The liver plays a major role in digestion, detoxification, and nutrient storage. 🧠 Explanation: The liver plays a major role in digestion, detoxification, and nutrient storage. 139 / 165 139. Consider the following statements: 1. The liver is the second largest gland in the human body. 2. It contains special cells that filter toxic substances. 3. It produces bile, an important digestive fluid. Which are correct? (a) Only 2 (b) 1 and 2 (c) 2 and 3 (d) All 1, 2, 3 🧠 Explanation: All are correct. The liver is the largest internal organ and performs many vital roles. 🧠 Explanation: All are correct. The liver is the largest internal organ and performs many vital roles. 140 / 165 140. Which part of the alimentary canal produces complete digestive juices? (a) Stomach (b) Small intestine (c) Large intestine (d) Salivary gland 🧠 Explanation: The small intestine, along with pancreas and liver secretions, produces complete digestive enzymes. 🧠 Explanation: The small intestine, along with pancreas and liver secretions, produces complete digestive enzymes. 141 / 165 141. Complete food digestion occurs in which part of the alimentary canal? (a) Stomach (b) Small intestine (c) Large intestine (d) None of these 🧠 Explanation: All digestion and absorption are completed in the small intestine. 🧠 Explanation: All digestion and absorption are completed in the small intestine. 142 / 165 142. Where does the undigested food go? (a) Mouth (b) Stomach (c) Large intestine (d) Small intestine 🧠 Explanation: Undigested food moves to the large intestine for water absorption and excretion. 🧠 Explanation: Undigested food moves to the large intestine for water absorption and excretion. 143 / 165 143. Which part of the small intestine is responsible for complete digestion? (a) Jejunum (b) Ileum (c) Duodenum (d) Colon 🧠 Explanation: The duodenum is where bile and pancreatic juices mix for complete digestion. 🧠 Explanation: The duodenum is where bile and pancreatic juices mix for complete digestion. 144 / 165 144. Consider the following statements: 1. Inner walls of the small intestine have villi that increase absorption. 2. Villi contain blood vessels and lymph to transport nutrients. 3. Digestive juices break down food to absorbable forms. Which are correct? (a) 1 and 2 (b) 2 and 3 (c) 1 and 3 (d) All 1, 2, 3 🧠 Explanation: All statements are correct. Villi help absorb digested nutrients efficiently 🧠 Explanation: All statements are correct. Villi help absorb digested nutrients efficiently 145 / 165 145. The part that absorbs digested food is— (a) Large intestine (b) Stomach (c) Small intestine (d) Mouth 🧠 Explanation: Absorption of nutrients into blood and lymph happens in the small intestine. 🧠 Explanation: Absorption of nutrients into blood and lymph happens in the small intestine. 146 / 165 146. Proteins are broken down into which simpler substances? (a) Sugars (b) Glucose (c) Amino acids (d) Fats 🧠 Explanation: Proteins are digested into amino acids, which are then absorbed. 🧠 Explanation: Proteins are digested into amino acids, which are then absorbed. 147 / 165 147. Which enzymes are involved in protein digestion? (a) Pepsin, Trypsin, Erepsin (b) Amylase, Lipase (c) Maltase, Sucrase (d) None of the above 🧠 Explanation: These are protein-digesting enzymes working in stomach and intestine. 🧠 Explanation: These are protein-digesting enzymes working in stomach and intestine. 148 / 165 148. Which of the following is incorrect? (a) Large intestine produces no digestive enzymes (b) Starch is converted to sugar by salivary enzymes (c) Large intestine absorbs most nutrients (d) Large intestine absorbs water and minerals 🧠 Explanation: Nutrients are absorbed in the small intestine, not the large intestine. 🧠 Explanation: Nutrients are absorbed in the small intestine, not the large intestine. 149 / 165 149. In which part is the enzyme called “Pepsin” found? Stomach 🧠 Explanation: Pepsin, a protein-digesting enzyme, is secreted by gastric glands in the stomach. 150 / 165 150. Which of the following is NOT correct? (a) Ammonia is converted to urea in the liver. (b) Undigested food is collected in the large intestine and removed. (c) Large intestine absorbs food and water. (d) Large intestine is the widest part of the alimentary canal 🧠 Explanation: Large intestine absorbs water and minerals, not food (nutrients are absorbed in small intestine). 🧠 Explanation: Large intestine absorbs water and minerals, not food (nutrients are absorbed in small intestine). 151 / 165 151. Which waste substances are present in human feces? (a) Salt (b) Undigested food (c) Water (d) None of these 🧠 Explanation: Feces consist mainly of undigested food, dead cells, and bacteria. 🧠 Explanation: Feces consist mainly of undigested food, dead cells, and bacteria. 152 / 165 152. Escherichia coli (E. coli) bacteria are found in which part of the alimentary canal? (a) Stomach (b) Rectum (c) Intestine (d) Liver 🧠 Explanation: E. coli is a beneficial bacteria living in the large intestine, helping in digestion and vitamin K production. 🧠 Explanation: E. coli is a beneficial bacteria living in the large intestine, helping in digestion and vitamin K production. 153 / 165 153. Which enzyme breaks down fats into fatty acids and glycerol? (a) Erepsin (b) Pepsin (c) Amylase (d) Lipase 🧠 Explanation: Lipase digests fats into fatty acids and glycerol. 🧠 Explanation: Lipase digests fats into fatty acids and glycerol. 154 / 165 154. Which of the following enzymes is not involved in protein digestion? (a) Trypsin (b) Pepsin (c) Amylase (d) Erepsin 🧠 Explanation: Amylase breaks down starch into sugars. It does not act on proteins. 🧠 Explanation: Amylase breaks down starch into sugars. It does not act on proteins. 155 / 165 155. What is the semi-liquid mass of food in the small intestine called? (a) Bolus (b) Chyme (c) Peptic Acid (d) Gastric Juice 🧠 Explanation: After digestion in the stomach, food becomes a semi-liquid mass called chyme, which passes into the small intestine. 🧠 Explanation: After digestion in the stomach, food becomes a semi-liquid mass called chyme, which passes into the small intestine. 156 / 165 156. In human digestion, starch is first broken into which sugar? Maltose 🧠 Explanation: Salivary amylase breaks starch into maltose, a disaccharide. 157 / 165 157. If a person's pancreas is removed, which digestive function is most affected? (a) Protein digestion (b) Carbohydrate digestion (c) Fat digestion (d) All of these 🧠 Explanation: The pancreas secretes enzymes for digestion of proteins, carbs, and fats, so all will be affected. 🧠 Explanation: The pancreas secretes enzymes for digestion of proteins, carbs, and fats, so all will be affected. 158 / 165 158. In which part are maltose, sucrose, and lactose digested? (a) Stomach (b) Small intestine (c) Large intestine (d) None of these 🧠 Explanation: These sugars are broken down into simple sugars by enzymes in the small intestine. 🧠 Explanation: These sugars are broken down into simple sugars by enzymes in the small intestine. 159 / 165 159. Which of the following is NOT a correct match about digestive glands? (d) Salivary gland – Intestinal juice 🧠 Explanation: Salivary glands produce saliva, not intestinal juice (which is secreted by intestinal walls). 160 / 165 160. Which of the following statements about enzymes is NOT true? (a) Steapsin breaks down fats into fatty acids and glycerol (b) Amylopsin converts starch into maltose (c) Trypsin breaks proteins into amino acids (d) None of these 🧠 Explanation: Trypsin breaks proteins into peptides, not amino acids. Erepsin completes the digestion to amino acids. 🧠 Explanation: Trypsin breaks proteins into peptides, not amino acids. Erepsin completes the digestion to amino acids. 161 / 165 161. What type of nutrition is followed by humans and animals? (a) Autotrophic (b) Saprophytic (c) Holozoic (d) Parasitic 🧠 Explanation: Holozoic nutrition involves ingestion, digestion, absorption, and egestion, as seen in humans and animals. 🧠 Explanation: Holozoic nutrition involves ingestion, digestion, absorption, and egestion, as seen in humans and animals. 162 / 165 162. Which cell organelle is associated with digestion in cells? (a) Golgi body (b) Mitochondria (c) Lysosome (d) Ribosome 🧠 Explanation: Lysosomes contain digestive enzymes that break down worn-out organelles and cellular debris. 🧠 Explanation: Lysosomes contain digestive enzymes that break down worn-out organelles and cellular debris. 163 / 165 163. Which gland produces saliva in the mouth? (a) Pituitary (b) Salivary gland (c) Pancreas (d) Thyroid 🧠 Explanation: Salivary glands produce saliva, which contains amylase to begin starch digestion. 🧠 Explanation: Salivary glands produce saliva, which contains amylase to begin starch digestion. 164 / 165 164. Which mineral is needed in the blood for clotting? (a) Magnesium (b) Manganese (c) Iron (d) Calcium 🧠 Explanation: Calcium ions are essential for blood clotting. 🧠 Explanation: Calcium ions are essential for blood clotting. 165 / 165 165. Which group shows correct classification of digestive glands and their secretions? Salivary glands → Saliva Liver → Bile Pancreas → Digestive enzymes Gastric gland → Gastric juice Salivary glands → Saliva Liver → Bile Pancreas → Digestive enzymes Gastric gland → Gastric juice Salivary glands → Saliva Liver → Bile Pancreas → Digestive enzymes Gastric gland → Gastric juice Your score isThe average score is 0% 0% Restart quiz Share via: Facebook X (Twitter) LinkedIn More
