Control and Coordination in Plants and Human Body Posted by By admin February 28, 2026 Control and Coordination in Plants and Human Body Control and Coordination in Plants and Human Body 1 / 202 1. What is the main function of the nervous system and hormones in the human body? (a) Production (b) Control (c) Circulation (d) Both A and B 🧠 Explanation: The nervous system and hormones primarily control and coordinate body functions. 🧠 Explanation: The nervous system and hormones primarily control and coordinate body functions. 2 / 202 2. Various chemical activities in the human body are controlled by— (a) Nervous system (b) Hormones (c) Both nervous system and hormones (d) All of these 🧠 Explanation: Both the nervous system and hormones regulate various chemical and metabolic processes. 🧠 Explanation: Both the nervous system and hormones regulate various chemical and metabolic processes. 3 / 202 3. What is the unusual property found in plant movements? (a) Nervous system (b) Muscular system (c) Nervous control (d) All of the above are absent 🧠 Explanation: Plants show movement without muscles or nerves. They rely on growth or chemical signals. 🧠 Explanation: Plants show movement without muscles or nerves. They rely on growth or chemical signals. 4 / 202 4. What is the movement in plants due to external stimuli called? (a) Spontaneous movement (b) Tropic movement (c) Nastic movement (d) Rhythmic movement 🧠 Explanation: Tropic movement occurs due to environmental stimuli like light or gravity. 🧠 Explanation: Tropic movement occurs due to environmental stimuli like light or gravity. 5 / 202 5. Root shows— (a) Positive geotropism and negative phototropism (b) Negative geotropism and positive phototropism (c) Positive phototropism (d) None of these 🧠 Explanation: Roots grow toward gravity and away from light. 🧠 Explanation: Roots grow toward gravity and away from light. 6 / 202 6. When a part of a plant bends toward or away from a stimulus like light, gravity, etc., the movement is called— (a) Phototropism (b) Geotropism (c) Chemotropism (d) Tropic movement 🧠 Explanation: General term for movement in response to stimuli is tropism. 🧠 Explanation: General term for movement in response to stimuli is tropism. 7 / 202 7. Which type of tropism is responsible for plant growth toward light? (a) Positive phototropism (b) Negative phototropism (c) Positive hydrotropism (d) None of these 🧠 Explanation: Shoots bend toward light (positive phototropism). 🧠 Explanation: Shoots bend toward light (positive phototropism). 8 / 202 9. Growth in plants occurs— (a) Always (b) Step by step (c) Throughout life (d) Growth does not occur in plants 🧠 Explanation: Plants can grow continuously, especially at meristematic regions. 🧠 Explanation: Plants can grow continuously, especially at meristematic regions. 9 / 202 8. Which hormone causes bending of shoot tip toward light? (a) Auxin (b) Cytokinin (c) Ethylene (d) Gibberellin 🧠 Explanation: Auxin promotes cell elongation on the shaded side, causing the shoot to bend toward light. 🧠 Explanation: Auxin promotes cell elongation on the shaded side, causing the shoot to bend toward light. 10 / 202 10. Consider the following statements: 1. Growth is a permanent change in plants. 2. Growth changes are mostly irreversible. Correct Answer: (c) Both 1 and 2 🧠 Explanation: Plant growth leads to permanent, irreversible changes in size and structure. 11 / 202 11. When a plant grows in circular pattern due to time and light changes, the movement is called— (a) Growth ring (b) Circadian rhythm (c) Circulatory movement (d) Annual ring 🧠 Explanation: Circadian rhythms are biological cycles responding to day-night changes. 🧠 Explanation: Circadian rhythms are biological cycles responding to day-night changes. 12 / 202 12. What is the reason for plant movements like opening and closing of stomata? (a) Photosynthesis (b) Respiration (c) Turgor pressure (d) Digestion 🧠 Explanation: Stomata open and close due to changes in turgor pressure of guard cells. 🧠 Explanation: Stomata open and close due to changes in turgor pressure of guard cells. 13 / 202 13. What type of movement do sunflowers show toward the Sun? a) Heliotropism (b) Thermotropism (c) Geotropism (d) None of these 🧠 Explanation: Heliotropism is movement toward sunlight, like sunflower heads tracking the sun. 🧠 Explanation: Heliotropism is movement toward sunlight, like sunflower heads tracking the sun. 14 / 202 14. Why do touch-me-not (Mimosa pudica) plant leaves fold when touched? (a) Due to change in turgor pressure (b) Due to chemical change (c) Due to temperature (d) Due to loss of turgor pressure 🧠 Explanation: Leaves collapse due to loss of turgor pressure in pulvini cells upon touch. 🧠 Explanation: Leaves collapse due to loss of turgor pressure in pulvini cells upon touch. 15 / 202 15. The bending of the shoot tip (apex) toward light is called— (a) Hydrotropism (b) Photoperiodism (c) Phototropism (d) Photosynthesis 🧠 Explanation: Bending of the shoot toward light is a typical example of phototropism. 🧠 Explanation: Bending of the shoot toward light is a typical example of phototropism. 16 / 202 16. Movement of the shoot tip in the opposite direction of light is called— (a) Negative phototropism (b) Positive phototropism (c) Hydrotropism (d) Geotropism 🧠 Explanation: Movement away from light is termed negative phototropism. 🧠 Explanation: Movement away from light is termed negative phototropism. 17 / 202 17. Bending of stem toward or away from gravity is an example of— (a) Phototropism (b) Movement of leaf base (c) Geotropism (d) Thigmotropism 🧠 Explanation: Movement related to gravity is called geotropism. 🧠 Explanation: Movement related to gravity is called geotropism. 18 / 202 18. Movement in plants due to external stimulus is called— (a) Spontaneous (b) Internal (c) Induced (d) Reflex 🧠 Explanation: Movement caused by external factors is induced. 🧠 Explanation: Movement caused by external factors is induced. 19 / 202 19. Which hormone is responsible for bending of stems toward light? (a) Auxin (b) Cytokinin (c) Gibberellin (d) Ethylene 🧠 Explanation: Auxin causes elongation of cells on the shaded side, bending the shoot toward light. 🧠 Explanation: Auxin causes elongation of cells on the shaded side, bending the shoot toward light. 20 / 202 20. Positive geotropism occurs in— (a) Roots (b) Stems (c) Buds (d) Flowers 🧠 Explanation: Roots grow toward gravity, so it is positive geotropism. 🧠 Explanation: Roots grow toward gravity, so it is positive geotropism. 21 / 202 21. Growth in a particular direction due to a specific stimulus is called— (a) Positive phototropism (b) Tropism (c) Response (d) Movement 🧠 Explanation: Directional growth due to external stimulus is tropism. 🧠 Explanation: Directional growth due to external stimulus is tropism. 22 / 202 22. What is geotropism? (a) Directional growth in plants due to gravity (b) Movement due to temperature (c) Movement due to light (d) Movement due to water 🧠 Explanation: Geo = Earth (gravity). So, geotropism is movement caused by gravity. 🧠 Explanation: Geo = Earth (gravity). So, geotropism is movement caused by gravity. 23 / 202 23. Who discovered the growth-regulating hormone found in plants? (a) Paal (b) Darwin (c) F. Went (d) Charles Darwin and F. Went 🧠 Explanation: F. W. Went discovered auxin, a key growth hormone in plants. 🧠 Explanation: F. W. Went discovered auxin, a key growth hormone in plants. 24 / 202 24. Cell division and plant growth are primarily controlled by— (a) Cytokinin (b) Gibberellin (c) Both cytokinin and gibberellin (d) All of the above 🧠 Explanation: Both cytokinin (promotes cell division) and gibberellin (promotes elongation) help in plant growth. 🧠 Explanation: Both cytokinin (promotes cell division) and gibberellin (promotes elongation) help in plant growth. 25 / 202 25. Which part of the plant produces most auxin hormone? (a) Shoot tip (b) Root tip (c) Lateral buds (d) All meristematic regions 🧠 Explanation: Auxin is primarily synthesized in shoot apices. 🧠 Explanation: Auxin is primarily synthesized in shoot apices. 26 / 202 26. Who first isolated auxin? (a) Horman Went (b) Koel (c) Darwin (d) Salkowski 🧠 Explanation: Frits Went (often miswritten as Horman Went) first isolated auxin. 🧠 Explanation: Frits Went (often miswritten as Horman Went) first isolated auxin. 27 / 202 27. Due to which hormone do plants bend toward light? (a) Cytokinin (b) Auxin (c) Ethylene (d) Gibberellin 🧠 Explanation: As before, auxin is responsible for bending due to light. 🧠 Explanation: As before, auxin is responsible for bending due to light. 28 / 202 29. Choose the correct statement— (a) Where auxin is more, that side grows more (b) Where auxin is less, that side grows more (c) Auxin is evenly distributed (d) Auxin reduces growth 🧠 Explanation: Auxin accumulates on the shaded side → more growth → bending toward light. 🧠 Explanation: Auxin accumulates on the shaded side → more growth → bending toward light. 29 / 202 28. Which hormone is most abundantly found in plant shoots? (a) Auxin (b) Gibberellin (c) Cytokinin (d) Ethylene 🧠 Explanation: Auxin is found abundantly in growing shoot tips. 🧠 Explanation: Auxin is found abundantly in growing shoot tips. 30 / 202 30. The type of plant movement due to environmental changes is called— (a) Passive movement (b) Nastic movement (c) Tropic movement (d) None of these 🧠 Explanation: Nastic movements occur due to external factors but are non-directional, e.g., touch-me-not. 🧠 Explanation: Nastic movements occur due to external factors but are non-directional, e.g., touch-me-not. 31 / 202 31. What is the characteristic of nastic movement? (a) Happens due to internal pressure changes (b) Only in root tip (c) Due to food availability (d) Only in shoot tip 🧠 Explanation: Turgor pressure changes cause nastic movement. 🧠 Explanation: Turgor pressure changes cause nastic movement. 32 / 202 32. Which movement is considered naturally inherited? (a) Tropic movement (b) Nastic movement (c) Reflex action (d) None of these 🧠 Explanation: Tropic movements are natural, inherent growth responses in plants. 🧠 Explanation: Tropic movements are natural, inherent growth responses in plants.🧠 Explanation: Tropic movements are natural, inherent growth responses in plants. 33 / 202 33. Auxin, which is used as a strong herbicide to kill dicot weeds, is— (a) IAA (b) IBA (c) NAA (d) 2,4-D 🧠 Explanation: 2,4-D is a synthetic auxin used to kill dicot weeds without harming monocots. 🧠 Explanation: 2,4-D is a synthetic auxin used to kill dicot weeds without harming monocots. 34 / 202 34. Auxin is mostly synthesized in— (a) Shoot apex (b) Root apex (c) Non-photosynthetic regions of roots (d) Non-photosynthetic regions of stem 🧠 Explanation: Auxins are mainly produced at the apical meristems of shoots. 🧠 Explanation: Auxins are mainly produced at the apical meristems of shoots. 35 / 202 35. Which of the following is a function of auxin hormone? (a) Promoting growth in apical and lateral organs (b) Formation of abscission layer (c) Root formation (d) All of the above 🧠 Explanation: Auxins regulate multiple processes, including growth, root formation, and leaf fall. 🧠 Explanation: Auxins regulate multiple processes, including growth, root formation, and leaf fall. 36 / 202 36. If a branch is cut and auxin is applied, then— (a) Roots will form (b) Callus (tissue mass) forms (c) Shoot will form (d) All of the above 🧠 Explanation: Auxins can promote rooting, callus formation, and shoot growth depending on conditions. 🧠 Explanation: Auxins can promote rooting, callus formation, and shoot growth depending on conditions. 37 / 202 37. Which of the following hormones promotes cell division? (a) Auxin (b) Cytokinin (c) Gibberellin (d) All of the above 🧠 Explanation: Cytokinin is primarily responsible for cell division. 🧠 Explanation: Cytokinin is primarily responsible for cell division. 38 / 202 38. Which of the following is used as a fruit ripening agent? (a) Indole Acetic Acid (IAA) (b) Abscisic Acid (ABA) (c) Ethylene / Ethaphon (d) None of these 🧠 Explanation: Ethylene (or ethaphon) is widely used to ripen fruits commercially. 🧠 Explanation: Ethylene (or ethaphon) is widely used to ripen fruits commercially. 39 / 202 39. Which hormone is responsible for cell elongation in plants? (a) Auxin (b) Ethylene (c) Ethaphon (d) Both A and B 🧠 Explanation: Auxins elongate cells in shoots and roots. 🧠 Explanation: Auxins elongate cells in shoots and roots. 40 / 202 40. Which plant hormone promotes the formation of seedless fruit (parthenocarpy)? (a) Auxin (b) Cytokinin (c) Ethylene (d) Abscisic acid 🧠 Explanation: Auxins can induce parthenocarpic (seedless) fruit formation without fertilization. 🧠 Explanation: Auxins can induce parthenocarpic (seedless) fruit formation without fertilization. 41 / 202 41. Which hormone helps in the production of seedless fruits? (a) Cytokinin (b) Auxin (c) Gibberellin (d) Auxin and Gibberellin both 🧠 Explanation: Auxins and gibberellins both aid parthenocarpy. 🧠 Explanation: Auxins and gibberellins both aid parthenocarpy. 42 / 202 42. Indole Acetic Acid (IAA), Indole Butyric Acid, Indole Propionic Acid, and Naphthalene Acetic Acid are— (a) Enzymes (b) Natural auxins (c) Synthetic auxins (d) Vitamins 🧠 Explanation: These are synthetic auxins, used in agriculture. 🧠 Explanation: These are synthetic auxins, used in agriculture. 43 / 202 43. Which of the following is a synthetic auxin? (a) 2,4-D (b) Indole Butyric Acid (c) Indole Acetic Acid (d) All of the above 🧠 Explanation: 2,4-D is widely known as a synthetic auxin used as a herbicide. 🧠 Explanation: 2,4-D is widely known as a synthetic auxin used as a herbicide. 44 / 202 44. Which of the following explains the use of gibberellins? (a) Breaking seed dormancy (b) Promoting flowering in off-season (c) Elongation of stem and fruit growth (d) All of the above 🧠 Explanation: Gibberellins are involved in stem elongation, flowering, and breaking seed dormancy. 🧠 Explanation: Gibberellins are involved in stem elongation, flowering, and breaking seed dormancy. 45 / 202 45. Which hormone promotes leaf fall and inhibits plant growth, making the plant turn away from light? (a) Auxin (b) Abscisic acid (c) Gibberellin (d) Cytokinin 🧠 Explanation: Abscisic acid is known as a stress hormone and promotes leaf fall and dormancy. 🧠 Explanation: Abscisic acid is known as a stress hormone and promotes leaf fall and dormancy. 46 / 202 46. Photoperiodism is controlled by which hormone? (a) Gibberellin (b) Ethylene (c) Cytokinin (d) Auxin 🧠 Explanation: Gibberellins play a role in flowering due to light duration (photoperiodism). 🧠 Explanation: Gibberellins play a role in flowering due to light duration (photoperiodism). 47 / 202 47. Which plant parts are used to extract gibberellins? (a) Root (b) Stem (c) Fungi (d) Leaves 🧠 Explanation: Gibberellins were first discovered in fungi (Gibberella fujikuroi). 🧠 Explanation: Gibberellins were first discovered in fungi (Gibberella fujikuroi). 48 / 202 48. Which hormone helps produce more flowers and fruits even in off-season? (a) Auxin (b) Cytokinin (c) Indole acetic acid (d) Gibberellin 🧠 Explanation: Auxins enhance flower and fruit production. 🧠 Explanation: Auxins enhance flower and fruit production. 49 / 202 49. In recent times, which natural and synthetic auxins are used as fertilizers to increase plant yield? (a) Indole acetic acid and Naphthalene acetic acid (b) Cytokinin and Gibberellin (c) Ethylene and Cytokinin (d) None of these 🧠 Explanation: IAA and NAA are used to improve crop yield 🧠 Explanation: IAA and NAA are used to improve crop yield 50 / 202 50. Which hormone helps in fruit ripening by converting starch to sugar? (a) Auxin (b) Gibberellin (c) Ethylene (d) None of these 🧠 Explanation: Ethylene promotes fruit ripening by converting starch into sugars. 🧠 Explanation: Ethylene promotes fruit ripening by converting starch into sugars. 51 / 202 51. Which hormone helps in fruit ripening by converting starch to sugar? (a) Ethylene (b) Auxin (c) Cytokinin (d) Both A and B 🧠 Explanation: Again, ethylene is the key hormone for this process. 🧠 Explanation: Again, ethylene is the key hormone for this process. 52 / 202 52. Which hormone delays senescence (aging) and helps in chlorophyll preservation? (a) Gibberellin (b) Ethylene (c) Cytokinin (d) Auxin 🧠 Explanation: Cytokinins delay leaf aging and help retain chlorophyll. 🧠 Explanation: Cytokinins delay leaf aging and help retain chlorophyll. 53 / 202 53. Which chemical is found in plants that works with auxins to help in division and nutrient mobilization? (a) Cytokinin (b) Ethylene (c) Abscisic acid (d) Auxin 🧠 Explanation: Cytokinins promote cell division and nutrient transport with auxins. 🧠 Explanation: Cytokinins promote cell division and nutrient transport with auxins. 54 / 202 54. Which hormone causes early fruit fall and leaf fall? (a) Cytokinin (b) Gibberellin (c) Auxin (d) Abscisic acid 🧠 Explanation: Abscisic acid is responsible for abscission (falling of parts). 🧠 Explanation: Abscisic acid is responsible for abscission (falling of parts).🧠 Explanation: Abscisic acid is responsible for abscission (falling of parts). 55 / 202 55. Which hormone helps in opening of cotyledons during seed germination? (a) Gibberellin (b) Abscisic acid (c) Cytokinin (d) Auxin 🧠 Explanation: Gibberellins break seed dormancy and help cotyledon expansion. 🧠 Explanation: Gibberellins break seed dormancy and help cotyledon expansion. 56 / 202 56. During seed dormancy, which hormone slows down food mobilization? (a) Cytokinin (b) Abscisic acid (ABA (c) Gibberellin (d) Auxin 🧠 Explanation: ABA keeps seeds dormant by slowing enzyme activity and food mobilization. 🧠 Explanation: ABA keeps seeds dormant by slowing enzyme activity and food mobilization. 57 / 202 57. Which hormone is responsible for early fruit ripening and increases bolting in plants like cabbage? (a) Auxin (b) Abscisic acid (c) Ethylene (d) C₂H₄ 🧠 Explanation: Ethylene and C₂H₄ are the same, and they promote ripening and bolting. 🧠 Explanation: Ethylene and C₂H₄ are the same, and they promote ripening and bolting. 58 / 202 58. What is the name of light-dependent flowering in plants? (a) Photoperiodism (b) Vernalization (c) Florigen (d) Dormancy 🧠 Explanation: Photoperiodism is the plant’s response to day length for flowering. 🧠 Explanation: Photoperiodism is the plant’s response to day length for flowering. 59 / 202 59. Which hormone removes the requirement for vernalization? (a) Gibberellin (b) Ethylene (c) Cytokinin (d) Auxin 🧠 Explanation: Gibberellins can substitute cold treatment needed in vernalization. 🧠 Explanation: Gibberellins can substitute cold treatment needed in vernalization. 60 / 202 60. Which hormone does not promote sugarcane juice production? (a) Increases juice in sugarcane (b) Gives energy to sugarcane life (c) Increases juice in fruits (d) Promotes photosynthesis 🧠 Explanation: Only option (b) is not a direct effect of gibberellins in sugarcane. 🧠 Explanation: Only option (b) is not a direct effect of gibberellins in sugarcane. 61 / 202 61. Which chemical is used to increase sugarcane juice? (a) IAA (b) Cytokinin (c) Ethylene (d) Gibberellin 🧠 Explanation: Gibberellins increase internode length and sugar content. 🧠 Explanation: Gibberellins increase internode length and sugar content. 62 / 202 62. What is the key hormone in seed dormancy? (a) Gibberellin (b) Auxin (c) Cytokinin (d) Abscisic acid (ABA) 🧠 Explanation: ABA maintains seed dormancy, especially under stress. 🧠 Explanation: ABA maintains seed dormancy, especially under stress. 63 / 202 63. Which hormone promotes apical dominance (suppression of lateral bud growth)? (a) Cytokinin (b) Gibberellin (c) Auxin (d) IAA 🧠 Explanation: Auxins, especially IAA, suppress side buds, promoting apical dominance. 🧠 Explanation: Auxins, especially IAA, suppress side buds, promoting apical dominance. 64 / 202 64. Which hormone is responsible for maintaining plant temperature balance (thermoregulation)? (a) Gibberellin (b) Ethylene (c) Cytokinin (d) Abscisic acid 🧠 Explanation: ABA controls stomatal closure under heat or drought stress. 🧠 Explanation: ABA controls stomatal closure under heat or drought stress. 65 / 202 65. Which hormone controls apical dominance? (a) Gibberellin (b) Cytokinin (c) IAA (d) Ethylene 🧠 Explanation: Repeated for emphasis: IAA, an auxin, is key in apical dominance. 🧠 Explanation: Repeated for emphasis: IAA, an auxin, is key in apical dominance. 66 / 202 66. Which hormone is mainly responsible for stomatal closure during water deficiency? (a) Ethylene (b) Abscisic acid (c) Cytokinin (d) Auxin 🧠 Explanation: ABA is the stress hormone that causes stomata to close. 🧠 Explanation: ABA is the stress hormone that causes stomata to close. 67 / 202 67. Which hormone is called the 'stress hormone'? (a) Ethylene (b) Abscisic acid (c) GA₃ (d) Natural auxin 🧠 Explanation: ABA helps plants cope with drought, salinity, and cold—hence called stress hormone. 🧠 Explanation: ABA helps plants cope with drought, salinity, and cold—hence called stress hormone. 68 / 202 68. In plants, which organelle is involved in the synthesis of Abscisic Acid (ABA)? (a) ER (Endoplasmic Reticulum) (b) Golgi apparatus (c) Chloroplast (d) Mitochondria 🧠 Explanation: ABA synthesis occurs in plastids (especially ER) and chloroplasts. 🧠 Explanation: ABA synthesis occurs in plastids (especially ER) and chloroplasts. 69 / 202 69. Which of the following hormones promotes growth in plants? (a) NAA (b) 2,4-D (c) ABA (d) IAA 🧠 Explanation: IAA (Indole Acetic Acid) is a natural auxin that promotes cell elongation and growth in plants. 🧠 Explanation: IAA (Indole Acetic Acid) is a natural auxin that promotes cell elongation and growth in plants. 70 / 202 70. What does Abscisic Acid (ABA) regulate? (a) Growth in root (b) Inhibition of cell division (c) Callus formation (d) Flowering and fruiting 🧠 Explanation: ABA is a growth-inhibiting hormone that stops cell division under stress. 🧠 Explanation: ABA is a growth-inhibiting hormone that stops cell division under stress. 71 / 202 71. What is the function of ABA during water deficiency? (a) As a guard for auxin (b) Helps in gibberellin production (c) Stimulates auxin function (d) Acts as a messenger for gibberellin 🧠 Explanation: ABA closes stomata to reduce water loss and acts as a protective signal. 🧠 Explanation: ABA closes stomata to reduce water loss and acts as a protective signal. 72 / 202 72. If you want to increase root and shoot growth for a crop, which combination of hormones would you use? (a) Auxin and ABA (b) Auxin and Cytokinin (c) IAA and Gibberellin (d) ABA and Ethylene 🧠 Explanation: IAA promotes root elongation, gibberellin promotes stem elongation—a good combo for full plant growth. 🧠 Explanation: IAA promotes root elongation, gibberellin promotes stem elongation—a good combo for full plant growth. 73 / 202 73. Which hormone promotes parthenocarpic fruit formation? (a) Auxin (b) Gibberellin (c) Ethylene (d) Cytokinin 🧠 Explanation: Auxins can induce parthenocarpy, producing seedless fruits. 🧠 Explanation: Auxins can induce parthenocarpy, producing seedless fruits. 74 / 202 74. Ethylene causes – (a) Accelerates fruit ripening, slows flower aging (b) Accelerates fruit ripening and aging (c) Prevents ripening and slows aging (d) None of these 🧠 Explanation: Ethylene speeds up both ripening and senescence (aging). 🧠 Explanation: Ethylene speeds up both ripening and senescence (aging). 75 / 202 75. Which hormone is found in seeds as a gas? (a) Cytokinin (b) Abscisic acid (c) Ethylene (d) Gibberellin 🧠 Explanation: Ethylene is the only plant hormone present as a gas, even in seeds. 🧠 Explanation: Ethylene is the only plant hormone present as a gas, even in seeds. 76 / 202 76. Which hormone induces flowering in pineapple and other plants? (a) ABA (b) Ethylene (c) Cytokinin (d) Auxin 🧠 Explanation: Auxins and ethylene can induce flowering in some species like pineapple. 🧠 Explanation: Auxins and ethylene can induce flowering in some species like pineapple. 77 / 202 77. Which of the following pairings is NOT correctly matched? (a) Auxin – For growth (b) Gibberellin – Stimulates photoperiodism (c) Cytokinin – Stimulates DNA synthesis (d) ABA – Dormancy hormone 🧠 Explanation: Photoperiodism is regulated by phytochromes, not directly by gibberellins. 🧠 Explanation: Photoperiodism is regulated by phytochromes, not directly by gibberellins. 78 / 202 78. Which statement is NOT true about hormones? (a) These are chemical messengers working in small amounts (b) They regulate specific plant parts differently (c) Different hormones act on different parts of plant (d) All of the above are incorrect 🧠 Explanation: All the above statements (a-c) are true, so (d) is incorrect. 🧠 Explanation: All the above statements (a-c) are true, so (d) is incorrect. 79 / 202 79. Which pigment helps plants absorb red and blue light for photosynthesis? (a) Xanthophyll (b) Phycocyanin (c) Cytokinin (d) Chlorophyll 🧠 Explanation: Chlorophyll absorbs red and blue wavelengths most effectively. 🧠 Explanation: Chlorophyll absorbs red and blue wavelengths most effectively. 80 / 202 80. Which hormone helps in converting etioplasts into chloroplasts in light? (a) Cytokinin (b) Gibberellin (c) ABA (d) IAA 🧠 Explanation: Gibberellins promote chloroplast development during greening. 🧠 Explanation: Gibberellins promote chloroplast development during greening. 81 / 202 81. Consider the following statements – 1. Light and temperature influence flowering. 2. Human hormones are synthesized in endocrine glands. Choose the correct answer: (a) Only 1 (b) Only 2 (c) Both 1 and 2 (d) Neither 1 nor 2 🧠 Explanation: Both are scientifically accurate statements. 🧠 Explanation: Both are scientifically accurate statements. 82 / 202 82. Consider the following – 1. Plant hormones control various growth processes. 2. One hormone controls only one specific part. Choose the correct answer: (a) Only 1 (b) Only 2 (c) Both 1 and 2 (d) Neither 1 nor 2 🧠 Explanation: Statement 2 is incorrect — one hormone may act on multiple parts. 🧠 Explanation: Statement 2 is incorrect — one hormone may act on multiple parts. 83 / 202 83. Which of the following is NOT true about hormones? (a) Secreted by specific organs (b) Affect only the organ that makes them (c) Their action is not limited to the secreting organ (d) Work in small amounts 🧠 Explanation: Hormones do not act only locally; they act at distant sites in the body or plant. 🧠 Explanation: Hormones do not act only locally; they act at distant sites in the body or plant. 84 / 202 84. Which part of the brain is involved in hormonal control? (a) Cerebellum (b) Pituitary gland 🧠 Explanation: The pituitary gland is the "master gland" controlling other endocrine glands. 85 / 202 85. Which gland produces releasing factors and inhibiting factors to regulate pituitary gland function? (a) Hypothalamus (b) Cerebellum (c) Thyroid (d) None of these 🧠 Explanation: The hypothalamus controls the pituitary gland via releasing and inhibiting hormones. 🧠 Explanation: The hypothalamus controls the pituitary gland via releasing and inhibiting hormones. 86 / 202 86. Which of the following is NOT true about the pituitary gland? (a) It is the smallest gland in the human body (b) It is called the master gland (c) It regulates hormone production from thyroid, adrenal, and gonads (d) It secretes growth hormone 🧠 Explanation: The pituitary is called the master gland, but it is not the smallest—the pineal gland is smaller. 🧠 Explanation: The pituitary is called the master gland, but it is not the smallest—the pineal gland is smaller. 87 / 202 87. Which of the following is NOT an endocrine gland? (a) Adrenal (b) Pituitary (c) Pancreas (d) Salivary gland 🧠 Explanation: Salivary glands are exocrine, not endocrine—they secrete through ducts. 🧠 Explanation: Salivary glands are exocrine, not endocrine—they secrete through ducts. 88 / 202 88. Which is the master gland of the human body? (a) Thyroid (b) Pituitary (c) Hypothalamus (d) Adrenal 🧠 Explanation: The pituitary gland controls other endocrine glands—hence, “master gland.” 🧠 Explanation: The pituitary gland controls other endocrine glands—hence, “master gland.” 89 / 202 89. The pituitary gland is controlled by another part of the brain. Which part is that? (a) Hypothalamus (b) Thyroid (c) Pineal (d) Thalamus 🧠 Explanation: Hypothalamus secretes releasing/inhibiting hormones that regulate the pituitary. 🧠 Explanation: Hypothalamus secretes releasing/inhibiting hormones that regulate the pituitary. 90 / 202 90. Consider the following statements – 1. Pituitary is the smallest endocrine gland. 2. Thyroid is the largest endocrine gland. 3. Hypothalamus controls the pituitary. Which of the above are correct? (c) 1, 2 and 3 🧠 Explanation: All three are true; pituitary is the smallest, thyroid is the largest, and hypothalamus controls pituitary. 91 / 202 91. Which hormone stimulates the thyroid gland to secrete thyroxine? (a) TSH (Thyroid Stimulating Hormone) (b) FSH (c) LTH (d) ACTH 🧠 Explanation: TSH, secreted by anterior pituitary, stimulates the thyroid to release thyroxine. 🧠 Explanation: TSH, secreted by anterior pituitary, stimulates the thyroid to release thyroxine. 92 / 202 93. Which part of the brain controls hormone secretion from the pituitary gland? (a) Hypothalamus (b) Pineal gland (c) Cerebellum (d) Thalamus 🧠 Explanation: The hypothalamus controls pituitary secretions. 🧠 Explanation: The hypothalamus controls pituitary secretions. 93 / 202 92. Consider the following – 1. Pituitary controls the functions of other endocrine glands. 2. Hypothalamus controls the pituitary. Which is/are correct? (c) Both 1 and 2 🧠 Explanation: Both statements are true. 94 / 202 94. Which is the most important gland in the human body? (a) Thyroid (b) Adrenal (c) Pituitary (d) Pancreas 🧠 Explanation: The pituitary regulates all other endocrine glands. 🧠 Explanation: The pituitary regulates all other endocrine glands. 95 / 202 95. Which hormone promotes the secretion of milk? (a) Insulin (b) Thyroxine (c) Prolactin (d) Adrenaline 🧠 Explanation: Prolactin, secreted by the pituitary, stimulates milk production 🧠 Explanation: Prolactin, secreted by the pituitary, stimulates milk production 96 / 202 96. Growth hormone (GH) secreted by the pituitary promotes – (a) Growth of bones and muscles (b) Hormone balance (c) Regulation of body temperature (d) None of these 🧠 Explanation: GH helps in the growth of bones and skeletal muscles. 🧠 Explanation: GH helps in the growth of bones and skeletal muscles. 97 / 202 97. Which gland is located in the sella turcica cavity of the skull? (a) Pituitary (b) Pineal (c) Hypothalamus (d) Cerebellum 🧠 Explanation: Sella turcica is a depression in the sphenoid bone that houses the pituitary gland. 🧠 Explanation: Sella turcica is a depression in the sphenoid bone that houses the pituitary gland. 98 / 202 98. Who is known as the Father of Endocrinology? (a) Schwann (b) Pasteur (c) Thomas Addison (d) William Harvey 🧠 Explanation: Thomas Addison studied adrenal insufficiency and is regarded as the father of endocrinology 🧠 Explanation: Thomas Addison studied adrenal insufficiency and is regarded as the father of endocrinology 99 / 202 99. Consider the following – 1. Excessive GH causes gigantism. 2. GH deficiency in childhood causes dwarfism. Which is/are correct? (c) Both 1 and 2 🧠 Explanation: Both are textbook facts of growth hormone imbalances. 100 / 202 101. Which of the following is not a hormone? (a) Adrenaline (b) Relaxin (c) Cortisone (d) Serotonin 🧠 Explanation: Serotonin is a neurotransmitter, not a hormone. The others are hormones. 🧠 Explanation: Serotonin is a neurotransmitter, not a hormone. The others are hormones. 101 / 202 102. Which hormone stimulates milk secretion in mammary glands? (a) FSH (b) LH (c) TSH (d) Prolactin 🧠 Explanation: Prolactin, secreted by the anterior pituitary, stimulates milk production. 🧠 Explanation: Prolactin, secreted by the anterior pituitary, stimulates milk production. 102 / 202 103. Which part of the brain is associated with the pituitary gland? (a) Cerebellum (b) Pons (c) Hypothalamus (d) Cerebrum 🧠 Explanation: The hypothalamus regulates the pituitary gland using releasing/inhibiting hormones. 🧠 Explanation: The hypothalamus regulates the pituitary gland using releasing/inhibiting hormones. 103 / 202 104. Which of these glands requires iodine to produce its hormone? (a) Parathyroid (b) Thyroid (c) Pituitary (d) Adrenal 🧠 Explanation: The thyroid gland needs iodine to synthesize thyroxine (T₄). 🧠 Explanation: The thyroid gland needs iodine to synthesize thyroxine (T₄). 104 / 202 105. Which gland is both endocrine and exocrine? (a) Pituitary (b) Pancreas (c) Adrenal (d) Parathyroid 🧠 Explanation: The pancreas has endocrine (insulin, glucagon) and exocrine (digestive enzymes) functions. 🧠 Explanation: The pancreas has endocrine (insulin, glucagon) and exocrine (digestive enzymes) functions. 105 / 202 106. Which gland’s malfunction causes diabetes? (a) Adrenal (b) Pituitary (c) Thyroid (d) Pancreas 🧠 Explanation: Diabetes mellitus results from insulin deficiency or resistance—pancreatic issue. 🧠 Explanation: Diabetes mellitus results from insulin deficiency or resistance—pancreatic issue. 106 / 202 107. What is Goiter? (a) A disease caused by lack/excess of hormones (b) A hereditary disease (c) A disease due to thyroid deficiency (d) A disease due to adrenal gland deficiency 🧠 Explanation: Goiter is usually caused by iodine deficiency leading to thyroid enlargement 🧠 Explanation: Goiter is usually caused by iodine deficiency leading to thyroid enlargement 107 / 202 108. What is the reason for excessive facial hair growth in some women? (a) Estrogen (b) Androgens (c) Prolactin (d) Relaxin 🧠 Explanation: Excess androgens (male sex hormones) in females cause hirsutism (excessive facial hair). 🧠 Explanation: Excess androgens (male sex hormones) in females cause hirsutism (excessive facial hair). 108 / 202 110. Which gland regulates biological clock and circadian rhythm? (a) Pituitary (b) Pineal (c) Hypothalamus (d) Thyroid 🧠 Explanation: The hypothalamus (specifically SCN - suprachiasmatic nucleus) regulates circadian rhythms. 🧠 Explanation: The hypothalamus (specifically SCN - suprachiasmatic nucleus) regulates circadian rhythms. 109 / 202 109. Consider the following statements – 1. In females, excessive testosterone is called virilism. 2. In males, symptoms like females may develop. Which is/are correct? (c) Both 1 and 2 🧠 Explanation: Both are true. Virilism in women, and gynecomastia in men result from hormonal imbalance. 110 / 202 111. What is the pineal gland related to? (a) Body temperature (b) Light-dark cycles (c) Thyroid hormones (d) Digestion 🧠 Explanation: The pineal gland secretes melatonin, which regulates the sleep-wake cycle. 🧠 Explanation: The pineal gland secretes melatonin, which regulates the sleep-wake cycle. 111 / 202 112. LH and FSH are known as – (a) Gonadotropic hormones (b) Phospholipids (c) Steroid hormones (d) None of these 🧠 Explanation: LH and FSH, secreted by the anterior pituitary, act on gonads—hence gonadotropins. 🧠 Explanation: LH and FSH, secreted by the anterior pituitary, act on gonads—hence gonadotropins. 112 / 202 113. Which of the following glands is both endocrine and exocrine in nature? (a) Pituitary (b) Pancreas (c) Adrenal (d) Testes 🧠 Explanation: The pancreas releases hormones (endocrine) and digestive enzymes (exocrine). 🧠 Explanation: The pancreas releases hormones (endocrine) and digestive enzymes (exocrine). 113 / 202 114. Which of the following is NOT a function of testis in humans? (a) Testosterone production (b) Urine formation (c) Sperm production (d) All are functions 🧠 Explanation: Testes produce sperm and testosterone, but do not form urine. 🧠 Explanation: Testes produce sperm and testosterone, but do not form urine. 114 / 202 115. Thyroid gland secretes thyroxine hormone which – (a) Helps in sexual development (b) Controls metabolism (c) Controls reproduction (d) Controls excretion 🧠 Explanation: Thyroxine regulates the metabolic rate of the body. 🧠 Explanation: Thyroxine regulates the metabolic rate of the body. 115 / 202 116. Which hormone is essential for sperm formation in testis? (a) Testosterone (b) Estrogen (c) Progesterone (d) Relaxin 🧠 Explanation: Testosterone, secreted by Leydig cells in the testes, is vital for spermatogenesis. 🧠 Explanation: Testosterone, secreted by Leydig cells in the testes, is vital for spermatogenesis. 116 / 202 117. What is the function of corpus luteum? (a) Secretes progesterone (b) Secretes testosterone (c) Secretes estrogen (d) None 🧠 Explanation: Corpus luteum, formed after ovulation, secretes progesterone to maintain pregnancy. 🧠 Explanation: Corpus luteum, formed after ovulation, secretes progesterone to maintain pregnancy. 117 / 202 118. Which hormone does the placenta secrete? (a) Progesterone (b) Estrogen (c) FSH (d) Oxytocin 🧠 Explanation: The placenta produces progesterone (and later estrogen) to support pregnancy. 🧠 Explanation: The placenta produces progesterone (and later estrogen) to support pregnancy. 118 / 202 119. Hormones that regulate each other’s opposite actions are called – (a) Target-seeking hormones (b) Antagonistic hormones (c) Receptor hormones (d) Pair hormones 🧠 Explanation: Antagonistic hormones perform opposite functions, like insulin and glucagon. 🧠 Explanation: Antagonistic hormones perform opposite functions, like insulin and glucagon. 119 / 202 120. Which of the following is an example of antagonistic hormones? (a) Calcitonin – Parathormone (b) Insulin – Glucagon (c) Estrogen – Progesterone (d) All of the above 🧠 Explanation: All listed pairs show opposite (antagonistic) hormonal effects. 🧠 Explanation: All listed pairs show opposite (antagonistic) hormonal effects. 120 / 202 121. Adrenaline and Noradrenaline are – (a) Life-saving hormones (b) Emergency hormones (c) Anti-inflammatory hormones (d) Waste hormones 🧠 Explanation: Also called fight-or-flight hormones, they help during stress or emergency. 🧠 Explanation: Also called fight-or-flight hormones, they help during stress or emergency. 121 / 202 122. Which hormone regulates blood pressure? (a) Thyroxine (b) Estrogen (c) Adrenaline (d) Insulin 🧠 Explanation: Adrenaline increases blood pressure by vasoconstriction. 🧠 Explanation: Adrenaline increases blood pressure by vasoconstriction. 122 / 202 123. Deficiency of Estrogen causes deficiency of which hormone? (a) Progesterone (b) Cortisone (c) FSH (d) Thyroxine 🧠 Explanation: Low estrogen can increase FSH due to lack of negative feedback on the pituitary. 🧠 Explanation: Low estrogen can increase FSH due to lack of negative feedback on the pituitary. 123 / 202 124. Which hormone helps the pancreas in absorbing glucose into body tissues? (a) Glucagon (b) Insulin (c) Estrogen (d) Testosterone 🧠 Explanation: Insulin helps cells absorb glucose from the bloodstream. 🧠 Explanation: Insulin helps cells absorb glucose from the bloodstream. 124 / 202 125. Consider the following statements – 1. Low insulin secretion causes Diabetes Mellitus. 2. High insulin secretion causes Hypoglycemia. Which is/are correct? (c) Both 1 and 2 🧠 Explanation: Both are correct. Insulin imbalance leads to blood sugar disorders. 125 / 202 126. Which hormone helps with spermatogenesis (sperm production)? (a) TSH (b) FSH (c) Thyroxine (d) All of these 🧠 Explanation: All three hormones affect male reproduction directly or indirectly. 🧠 Explanation: All three hormones affect male reproduction directly or indirectly. 126 / 202 127. What causes cretinism in children? (a) Excess GH (b) GH deficiency (c) Excess thyroxine (d) Thyroxine deficiency 🧠 Explanation: Cretinism is caused by congenital hypothyroidism → low thyroxine 🧠 Explanation: Cretinism is caused by congenital hypothyroidism → low thyroxine 127 / 202 128. Which hormone is considered the master hormone in humans? (a) FSH (b) TSH (c) ACTH (d) MSH 🧠 Explanation: TSH (Thyroid Stimulating Hormone) controls the thyroid and metabolism. 🧠 Explanation: TSH (Thyroid Stimulating Hormone) controls the thyroid and metabolism. 128 / 202 129. Which hormone has no specific target organ? (a) Growth hormone (b) Oxytocin (c) Parathormone (d) None of the above 🧠 Explanation: All listed hormones have specific target tissues 🧠 Explanation: All listed hormones have specific target tissues 129 / 202 130. Which gland secretes life-saving hormone? (a) Pituitary (b) Thyroid (c) Adrenal (d) Estrogen 🧠 Explanation: Adrenaline, secreted by adrenal gland, is life-saving in emergencies. 🧠 Explanation: Adrenaline, secreted by adrenal gland, is life-saving in emergencies. 130 / 202 131. Which hormone is considered an anti-allergic hormone? (a) Cortisone (b) Progesterone (c) Estrogen (d) None of these 🧠 Explanation: Cortisone (a corticosteroid) suppresses inflammation and allergies. 🧠 Explanation: Cortisone (a corticosteroid) suppresses inflammation and allergies. 131 / 202 132. Which hormone is called the "emergency hormone"? (a) Cortisone (b) Adrenaline (c) Thyroxine (d) Insulin 🧠 Explanation: Adrenaline prepares the body to respond to stress (fight-or-flight). 🧠 Explanation: Adrenaline prepares the body to respond to stress (fight-or-flight). 132 / 202 133. Which gland stores excess iodine in the body? (a) Thyroid (b) Parathyroid (c) Pituitary (d) Thymus 🧠 Explanation: The thyroid stores iodine to make T3 and T4 hormones. 🧠 Explanation: The thyroid stores iodine to make T3 and T4 hormones. 133 / 202 134. What is the disease caused by iron deficiency? (a) Rickets (b) Anemia (c) Acromegaly (d) Kwashiorkor 🧠 Explanation: Iron deficiency → reduced hemoglobin → anemia. 🧠 Explanation: Iron deficiency → reduced hemoglobin → anemia. 134 / 202 135. Where is Gonadotropin-Releasing Hormone (GnRH) secreted from? (a) Blood (b) Ovary (c) Adrenal (d) Hypothalamus 🧠 Explanation: GnRH is secreted by the hypothalamus to regulate LH & FSH. 🧠 Explanation: GnRH is secreted by the hypothalamus to regulate LH & FSH. 135 / 202 136. Which of the following is not secreted by the thyroid gland? (a) Thyroxine (b) Triiodothyronine 🧠 Explanation: This is a trick question. Actually, the thyroid secretes both T3 (Triiodothyronine) and T4 (Thyroxine). If the options intend to ask which is not directly secreted in large amounts, then T3 is partially correct, as it's mainly formed from T4 in tissues. 136 / 202 137. Which hormone increases heart rate to supply more oxygen to our muscles? (a) Insulin (b) Thyroxine (c) Cortisone (d) FSH 🧠 Explanation: Thyroxine increases metabolism and heart rate, aiding oxygen delivery 🧠 Explanation: Thyroxine increases metabolism and heart rate, aiding oxygen delivery 137 / 202 138. Islets of Langerhans are found in – (a) Alpha cells (b) Beta cells (c) Delta cells (d) None 🧠 Explanation: Beta cells of pancreas release insulin. 🧠 Explanation: Beta cells of pancreas release insulin. 138 / 202 140. Which gland secretes sex hormones? (a) Pituitary (b) Thyroid (c) Adrenal (d) Parathyroid 🧠 Explanation: Though gonads are primary, adrenal gland also secretes sex hormones (androgens). 🧠 Explanation: Though gonads are primary, adrenal gland also secretes sex hormones (androgens). 139 / 202 141. Choose the correct statements about hormones – 1. They are steroids, proteins, or amino acids. 2. They are produced in one part of the body and affect another. 3. They don’t affect the organ they are secreted from. 4. They help enzymes perform their work. Correct answer: (a) 1 and 2 🧠 Explanation: Hormones are chemicals that affect distant organs. 140 / 202 142. Hormones in the pituitary and adrenal glands are made of – (a) Protein (b) Amino acid (c) Steroid fats (d) All of the above 🧠 Explanation: Hormones can be protein-based, steroid-based, or amino acid derivatives. 🧠 Explanation: Hormones can be protein-based, steroid-based, or amino acid derivatives. 141 / 202 143. Thyroid hormones are made from – (a) Phenylalanine and amino acids (b) Phenylalanine only (c) Steroids (d) Proteins 🧠 Explanation: Actually, thyroid hormones are amino acid-based, not steroid. Correct answer should be (a), not (c). There's likely a mistake in the key if marked differently. 🧠 Explanation: Actually, thyroid hormones are amino acid-based, not steroid. Correct answer should be (a), not (c). There's likely a mistake in the key if marked differently. 142 / 202 145. Which hormone causes labor pain during childbirth? (a) Relaxin (b) Prolactin (c) Oxytocin (d) Estrogen 🧠 Explanation: Oxytocin stimulates uterine contractions during labor. 🧠 Explanation: Oxytocin stimulates uterine contractions during labor. 143 / 202 144. Which gland stores steroid hormones? (a) Adrenal cortex (b) Testes (c) Ovaries (d) All of the above 🧠 Explanation: Adrenal cortex stores and secretes steroid hormones. 🧠 Explanation: Adrenal cortex stores and secretes steroid hormones. 144 / 202 146. Which hormone is secreted by the placenta? (a) Estrogen (b) Relaxin (c) Gonadotropin (d) All of the above 🧠 Explanation: The placenta secretes multiple hormones to support pregnancy. 🧠 Explanation: The placenta secretes multiple hormones to support pregnancy. 145 / 202 147. What is androgens? (a) Male hormones (b) Female hormones (c) Digestive enzymes (d) None of the above 🧠 Explanation: Androgens are male sex hormones, like testosterone. 🧠 Explanation: Androgens are male sex hormones, like testosterone. 146 / 202 148. Which disease is caused due to lack of thyroxine? (a) Goiter (b) Arthritis (c) Cretinism (d) Addison's disease 🧠 Explanation: Cretinism occurs due to thyroxine deficiency in children. 🧠 Explanation: Cretinism occurs due to thyroxine deficiency in children. 147 / 202 149. Which hormone helps in the growth of body hairs? (a) Androgen (b) Estrogen (c) Insulin (d) FSH 🧠 Explanation: Androgens promote body and facial hair growth. 🧠 Explanation: Androgens promote body and facial hair growth. 148 / 202 151. What is "Adam's Apple"? (a) Thyroid organ (b) Larynx (c) Enlargement of thyroid cartilage (d) Thyroxine layer 🧠 Explanation: Adam’s Apple is the visible thyroid cartilage of the larynx 🧠 Explanation: Adam’s Apple is the visible thyroid cartilage of the larynx 149 / 202 150. Which hormone is also called non-steroid hormone? (a) Progesterone (b) Relaxin (c) Insulin (d) Estrogen 🧠 Explanation: Insulin is a protein hormone, hence non-steroid. 🧠 Explanation: Insulin is a protein hormone, hence non-steroid. 150 / 202 152. Which gland is called the master of all glands? (a) Pineal (b) Pituitary (c) Thyroid (d) Hypothalamus 🧠 Explanation: The pituitary gland controls many other endocrine glands. 🧠 Explanation: The pituitary gland controls many other endocrine glands. 151 / 202 153. What happens if insulin secretion decreases in a patient? (a) Goiter (b) Diabetes (c) Dwarfism (d) None of these 🧠 Explanation: Insulin deficiency leads to diabetes mellitus. 🧠 Explanation: Insulin deficiency leads to diabetes mellitus. 152 / 202 154. Which is the fastest acting hormone? (a) Adrenaline (b) Thyroid hormone (c) Insulin (d) Estrogen 🧠 Explanation: Adrenaline acts instantly during emergencies (fight-or-flight). 🧠 Explanation: Adrenaline acts instantly during emergencies (fight-or-flight). 153 / 202 155. Which hormone controls absorption of calcium in the intestine? (a) Thyroxine (b) Parathyroid hormone (c) Insulin (d) ACTH 🧠 Explanation: Parathyroid hormone (PTH) increases calcium absorption from the gut. 🧠 Explanation: Parathyroid hormone (PTH) increases calcium absorption from the gut. 154 / 202 156. Which hormone opposes the action of insulin? (a) Adrenaline (b) Glucagon (c) Cortisone (d) Both (b) and (c) 🧠 Explanation: Glucagon increases blood sugar levels, opposing insulin, which lowers it. 🧠 Explanation: Glucagon increases blood sugar levels, opposing insulin, which lowers it. 155 / 202 157. Which plant hormone helps plants to close stomata and tolerate cold? (a) ABA (b) IAA (c) Cytokinin (d) Gibberellin 🧠 Explanation: ABA (Abscisic Acid) is a stress hormone, promotes stomatal closure during drought/cold. 🧠 Explanation: ABA (Abscisic Acid) is a stress hormone, promotes stomatal closure during drought/cold. 156 / 202 158. Consider the following statements: 1. Cortisol increases blood sugar level. 2. Parathormone increases blood calcium level. (c) Both 1 and 2 🧠 Explanation: Both statements are correct — cortisol (a glucocorticoid) raises glucose, and parathormone raises calcium. 157 / 202 159. What causes narrowing of arteries? (a) Heart disease (b) High fat (c) Smoking (d) All of the above 🧠 Explanation: All listed factors can cause narrowing and hardening of arteries. 🧠 Explanation: All listed factors can cause narrowing and hardening of arteries. 158 / 202 160. Which of the following is not a function of the nervous system? (a) Sensory reception (b) Production of food (c) Coordination (d) Nerve conduction 🧠 Explanation: Food production is not a nervous system function. 🧠 Explanation: Food production is not a nervous system function. 159 / 202 161. Consider the following statements: 1. A neuron has one axon and many dendrites. 2. Nerves are formed by a bundle of axons. (c) Both 1 and 2 🧠 Explanation: Both are correct. Neurons have one axon, multiple dendrites, and nerves are bundles of axons. 160 / 202 162. What is the main function of a nerve cell (neuron)? (a) Movement (b) Conduction of impulse (c) Growth (d) Secretion 🧠 Explanation: Neurons primarily conduct nerve impulses. 🧠 Explanation: Neurons primarily conduct nerve impulses. 161 / 202 163. Where is the nucleus present in a neuron? (a) Cell body (b) Axon (c) Dendrite (d) None 🧠 Explanation: The nucleus of a neuron is in the soma (cell body). 🧠 Explanation: The nucleus of a neuron is in the soma (cell body). 162 / 202 164. What is it called when one neuron connects to another? (a) Nerve fibers (b) Nerve muscle (c) Synapse (d) Node of Ranvier 🧠 Explanation: A synapse is the junction between two neurons. 🧠 Explanation: A synapse is the junction between two neurons. 163 / 202 165. When a neuron connects to a muscle fiber, what is the junction called? (a) Synapse (b) Neuromuscular junction (c) Synaptic cleft (d) Myelin gap 🧠 Explanation: Neuromuscular junction is the point of contact between neuron and muscle. 🧠 Explanation: Neuromuscular junction is the point of contact between neuron and muscle. 164 / 202 166. What is the space between two neurons or muscle fibers called? (a) Synapse (b) Neuromuscular junction (c) Synaptic cleft (d) Myelin sheath 🧠 Explanation: Synaptic cleft is the gap between two neurons at a synapse. 🧠 Explanation: Synaptic cleft is the gap between two neurons at a synapse. 165 / 202 168. In which part of the neuron is the Golgi apparatus not found? (a) Axon (b) Dendrite (c) Cytoplasm (d) Cell body 🧠 Explanation: Golgi bodies are found in the soma, not in axons. 🧠 Explanation: Golgi bodies are found in the soma, not in axons. 166 / 202 167. Who won the Nobel Prize in 1906 for research on neurons? (a) Ramón y Cajal (b) Watson and Crick (c) Sydney Brenner (d) Ivan Pavlov 🧠 Explanation: Santiago Ramón y Cajal received the Nobel Prize in 1906 for his work on neuron structure. 🧠 Explanation: Santiago Ramón y Cajal received the Nobel Prize in 1906 for his work on neuron structure. 167 / 202 169. Which ion is required for transmission of electrical impulses in neurons? (a) Sodium (b) Potassium (c) Both 1 and 2 (d) Chloride 🧠 Explanation: Sodium and potassium are critical for nerve impulse conduction. 🧠 Explanation: Sodium and potassium are critical for nerve impulse conduction. 168 / 202 170. Consider the following statements: 1. Myelin sheath insulates the axon and speeds conduction. 2. Nodes of Ranvier increase impulse speed by saltatory conduction. 3. Non-myelinated neurons lack myelin sheath. Correct answer: (d) All of the above 🧠 Explanation: All are true and describe myelinated vs unmyelinated neurons. 169 / 202 171. What do Schwann cells produce? (a) Myelin sheath (b) Neurotransmitters (c) RBCs (d) WBCs 🧠 Explanation: Schwann cells produce the myelin sheath in peripheral nerves. 🧠 Explanation: Schwann cells produce the myelin sheath in peripheral nerves. 170 / 202 172. What is a bipolar neuron? (a) One axon and one dendrite (b) One axon and two or more dendrites (c) Many axons (d) None 🧠 Explanation: A bipolar neuron has one axon and one dendrite 🧠 Explanation: A bipolar neuron has one axon and one dendrite 🧠 Explanation: A bipolar neuron has one axon and one dendrite 171 / 202 173. Who discovered the myelin sheath surrounding the axon? (a) Axon (b) Schwann cells (c) Cytoplasm of neuron (d) Muscle fibers 🧠 Explanation: Schwann cells form the myelin sheath in peripheral neurons. 🧠 Explanation: Schwann cells form the myelin sheath in peripheral neurons. 172 / 202 174. Where does the synapse occur? (a) Between two dendrites (b) Between axon of one neuron and dendrite of another (c) Between cell bodies (d) Between axon and axon 🧠 Explanation: A synapse is the junction between axon and dendrite of different neurons. 🧠 Explanation: A synapse is the junction between axon and dendrite of different neurons. 173 / 202 175. What is not part of the central nervous system? (a) Reflex arc (b) Brain (c) Spinal cord (d) Both brain and spinal cord 🧠 Explanation: Reflex arc involves peripheral nervous system, not CNS directly. 🧠 Explanation: Reflex arc involves peripheral nervous system, not CNS directly. 174 / 202 176. What hormone influences the uterus to contract during childbirth? (a) Estrogen (b) Oxytocin (c) Progesterone (d) Relaxin 🧠 Explanation: Oxytocin stimulates uterine contractions during labor. 🧠 Explanation: Oxytocin stimulates uterine contractions during labor. 175 / 202 177. How many parts is the human brain divided into? (a) 2 (b) 3 (c) 5 (d) 4 🧠 Explanation: The brain is functionally divided into 5 parts: cerebrum, cerebellum, medulla, pons, midbrain. 🧠 Explanation: The brain is functionally divided into 5 parts: cerebrum, cerebellum, medulla, pons, midbrain. 176 / 202 178. Which of the following does NOT relate to the cerebrum? (a) It is the largest part of the brain (b) It controls higher mental functions (c) Some parts control speech (d) None of the above 🧠 Explanation: All statements are true, so none is incorrect. 🧠 Explanation: All statements are true, so none is incorrect. 177 / 202 179. The folded part of the cerebral hemisphere is called? (a) Sulcus (b) Gyrus (c) Cerebral convolution (d) Lobe 🧠 Explanation: The folds and grooves of the cerebrum are called convolutions. 🧠 Explanation: The folds and grooves of the cerebrum are called convolutions. 178 / 202 180. Where is the center for hearing, memory, and speech located? (a) Cerebrum (b) Cerebellum (c) Temporal lobe (d) Medulla 🧠 Explanation: Temporal lobe of cerebrum controls hearing and memory. 🧠 Explanation: Temporal lobe of cerebrum controls hearing and memory. 179 / 202 181. Which part of the brain controls involuntary movements like heartbeat and breathing? (a) Midbrain (b) Cerebrum (c) Pons (d) Medulla oblongata 🧠 Explanation: Medulla oblongata regulates involuntary functions. 🧠 Explanation: Medulla oblongata regulates involuntary functions. 180 / 202 182. Which part of the brain regulates heartbeat, respiration, and blood pressure? (a) Cerebrum (b) Cerebellum (c) Medulla oblongata (d) Pons 🧠 Explanation: Again, the medulla oblongata is responsible for autonomic functions. 🧠 Explanation: Again, the medulla oblongata is responsible for autonomic functions. 181 / 202 183. What percentage of body weight is made up of blood? (a) 6% (b) 8% (c) 10% (d) 2% 🧠 Explanation: Blood is approximately 8-10% of total body weight. 10% is the closest correct choice. 🧠 Explanation: Blood is approximately 8-10% of total body weight. 10% is the closest correct choice. 182 / 202 184. What is the average blood volume in an adult human? (a) 800 mL (b) 1200 mL (c) 1400 mL (d) 1600 mL 🧠 Explanation: Average blood volume is about 5–6 liters, but this question likely refers to per unit — however, this seems misprinted. Correct average is 5000–6000 mL. 🧠 Explanation: Average blood volume is about 5–6 liters, but this question likely refers to per unit — however, this seems misprinted. Correct average is 5000–6000 mL. 183 / 202 185. What is the average weight of human brain? (a) 1350 g (b) 1230 g (c) 1000 g (d) 1100 g 🧠 Explanation: Average adult brain weight is 1350–1400 grams. 🧠 Explanation: Average adult brain weight is 1350–1400 grams. 184 / 202 186. Which statement is true regarding cerebellum? (a) Cerebellum and pons together are part of hindbrain (b) It controls blood pressure (c) It regulates hormonal functions (d) None of the above 🧠 Explanation: Cerebellum and pons are part of the hindbrain. 🧠 Explanation: Cerebellum and pons are part of the hindbrain. 185 / 202 187. The tough connective tissue covering the brain and spinal cord is called? (a) Gyrus (b) Sulcus (c) Meninges (d) None 🧠 Explanation: The meninges are protective membranes around brain and spinal cord 🧠 Explanation: The meninges are protective membranes around brain and spinal cord 186 / 202 188. The part of the brain located behind the cerebrum is called? (a) Medulla (b) Pons (c) Cerebellum (d) Cerebrum 🧠 Explanation: Cerebellum lies behind cerebrum, under occipital lobe. 🧠 Explanation: Cerebellum lies behind cerebrum, under occipital lobe. 187 / 202 189. Which part of the brain controls emotions and feelings? (a) Cerebrum (b) Medulla (c) Limbic system (d) Pons 🧠 Explanation: The limbic system controls emotions, memory, and behavior 🧠 Explanation: The limbic system controls emotions, memory, and behavior 188 / 202 190. Consider the following statements about the cerebellum: 1. Cerebellum helps in maintaining balance and body posture. 2. It also regulates voluntary muscular activities. Correct answer: (c) Both 1 and 2 🧠 Explanation: Both are true — cerebellum manages balance and motor control. 189 / 202 191. Which part of the human brain controls swallowing and vomiting? (a) Cerebrum (b) Cerebellum (c) Medulla (d) Pons 🧠 Explanation: The medulla oblongata controls involuntary actions like vomiting, swallowing, and breathing. 🧠 Explanation: The medulla oblongata controls involuntary actions like vomiting, swallowing, and breathing. 190 / 202 192. Which part of the human brain regulates hunger, thirst, and body temperature? (a) Cerebral peduncle (b) Thalamus (c) Cerebrum (d) Hypothalamus 🧠 Explanation: The hypothalamus regulates hunger, thirst, temperature, and homeostasis. 🧠 Explanation: The hypothalamus regulates hunger, thirst, temperature, and homeostasis. 191 / 202 193. Which part of the brain regulates pain due to extreme cold or heat? (a) Cerebrum (b) Cerebellum (c) Midbrain (d) Hypothalamus 🧠 Explanation: The hypothalamus helps manage pain responses from external stimuli like heat/cold. 🧠 Explanation: The hypothalamus helps manage pain responses from external stimuli like heat/cold. 192 / 202 194. If a part of the cerebrum is damaged due to some reason— (a) Hands and legs will stop functioning (b) Thinking ability is affected (c) Speech will stop (d) All of the above 🧠 Explanation: The cerebrum controls voluntary actions, thoughts, and speech, so all are affected. 🧠 Explanation: The cerebrum controls voluntary actions, thoughts, and speech, so all are affected. 193 / 202 195. How many pairs of cranial nerves are there in the human body? (a) 12 (b) 13 (c) 12 pairs (d) 32 🧠 Explanation: Humans have 12 pairs of cranial nerves that originate from the brain. 🧠 Explanation: Humans have 12 pairs of cranial nerves that originate from the brain. 194 / 202 196. How many pairs of spinal nerves are there in the human body? (a) 15 (b) 31 (c) 12 (d) 31 pairs 🧠 Explanation: There are 31 pairs of spinal nerves in the human body 🧠 Explanation: There are 31 pairs of spinal nerves in the human body 195 / 202 197. What is the name of the membrane covering the upper part of the brain? (a) Pia mater (b) Dura mater (c) Arachnoid mater (d) Hypothalamus 🧠 Explanation: The arachnoid mater is the middle layer of meninges covering the brain and spinal cord. 🧠 Explanation: The arachnoid mater is the middle layer of meninges covering the brain and spinal cord. 196 / 202 198. Which part of the brain controls reflex actions? (a) Medulla (b) Midbrain (c) Cerebrum (d) Cerebellum 🧠 Explanation: Reflex actions are coordinated by the medulla oblongata and spinal cord 🧠 Explanation: Reflex actions are coordinated by the medulla oblongata and spinal cord 197 / 202 199. When something suddenly comes near the eyes and the eyelids blink— this is what type of action? (a) Voluntary reflex (b) Involuntary reflex (c) Acquired reflex (d) None of these 🧠 Explanation: This is a classic involuntary reflex action — an automatic protective response. 🧠 Explanation: This is a classic involuntary reflex action — an automatic protective response. 198 / 202 200. Consider the following about the brain stem: 1. It controls involuntary actions. 2. It controls vital functions like heartbeat and respiration. Correct Answer: (c) Both 1 and 2 🧠 Explanation: The brain stem (medulla, pons, midbrain) regulates involuntary and vital functions. 199 / 202 201. Which neurotransmitter is produced by the sympathetic nervous system? (a) Adrenaline (b) Noradrenaline (c) Acetylcholine (d) All of these 🧠 Explanation: The sympathetic nervous system uses multiple neurotransmitters including adrenaline and noradrenaline. 🧠 Explanation: The sympathetic nervous system uses multiple neurotransmitters including adrenaline and noradrenaline. 200 / 202 202. Where is the optic chiasma (crossing of optic nerves) seen? (a) Cerebrum (b) Midbrain (c) Cerebellum (d) Hindbrain 🧠 Explanation: The optic chiasma, where optic nerves cross, is located near the midbrain. 🧠 Explanation: The optic chiasma, where optic nerves cross, is located near the midbrain. 201 / 202 203. In Alzheimer's disease, which part of the brain is mainly affected? (a) Cerebellum (b) Cerebrum (c) Brain stem (d) Thalamus 🧠 Explanation: Alzheimer's mainly affects the cerebrum, especially hippocampus (memory center). 🧠 Explanation: Alzheimer's mainly affects the cerebrum, especially hippocampus (memory center). 202 / 202 204. What is 'Brain Sand' in the pineal gland called? (a) Calcium (b) Magnesium (c) Iron (d) Corpora arenacea 🧠 Explanation: Brain sand refers to corpora arenacea, calcium deposits in the pineal gland. 🧠 Explanation: Brain sand refers to corpora arenacea, calcium deposits in the pineal gland. Your score isThe average score is 0% 0% Restart quiz Share via: Facebook X (Twitter) LinkedIn More
