NCERT Book Class 10th SCIENCE MCQ
Chapter 5 : Life Processes
Multiple-Choice Questions (MCQs) with Answers
1. An example of autotrophic nutrition is:
a) Human
b) Cow
c) Green plant
d) Fungus
Answer: c) Green plant
2. During photosynthesis, oxygen is produced from:
a) Carbon dioxide
b) Water
c) Glucose
d) Chlorophyll
Answer: b) Water
3. In humans, digestion begins in:
a) Stomach
b) Mouth
c) Small intestine
d) Esophagus
Answer: b) Mouth
4. Bile juice is stored in:
a) Liver
b) Pancreas
c) Gallbladder
d) Stomach
Answer: c) Gallbladder
5. Deficiency of Vitamin C causes which disease?
a) Night blindness
b) Scurvy
c) Beriberi
d) Rickets
Answer: b) Scurvy
6. The main respiratory organ in humans is:
a) Liver
b) Kidney
c) Lungs
d) Heart
Answer: c) Lungs
7. Exchange of gases in the air occurs in:
a) Trachea
b) Alveoli
c) Lungs
d) Diaphragm
Answer: b) Alveoli
8. In anaerobic respiration, what is produced?
a) CO₂ + H₂O
b) CO₂ + Ethanol
c) O₂ + Glucose
d) O₂ + CO₂
Answer: b) CO₂ + Ethanol
9. The respiratory rate in humans is controlled by:
a) Liver
b) Brain
c) Heart
d) Lungs
Answer: b) Brain
10. In respiration, energy is released in the form of:
a) ATP
b) ADP
c) NADPH
d) FADH
Answer: a) ATP
11. The red color of human blood is due to:
a) Plasma
b) Hemoglobin
c) Leukocytes
d) Platelets
Answer: b) Hemoglobin
12. How many chambers are present in the human heart?
a) 2
b) 3
c) 4
d) 5
Answer: c) 4
13. What do arteries carry?
a) Only oxygenated blood
b) Only deoxygenated blood
c) Both oxygenated and deoxygenated blood
d) Digestive juices
Answer: c) Both oxygenated and deoxygenated blood
14. In plants, water is transported through:
a) Phloem
b) Xylem
c) Cambium
d) Stomata
Answer: b) Xylem
15. The function of the lymphatic system is:
a) Transport of nutrients
b) Providing immunity
c) Hormone secretion
d) Both (a) and (b)
Answer: d) Both (a) and (b)
16. The main excretory organ in humans is:
a) Liver
b) Kidney
c) Skin
d) Lungs
Answer: b) Kidney
17. Nephron is the functional unit of:
a) Liver
b) Heart
c) Kidney
d) Lungs
Answer: c) Kidney
18. Which substance is not present in urine?
a) Urea
b) Glucose
c) Salts
d) Water
Answer: b) Glucose
19. In plants, excretory products are stored in:
a) Leaves
b) Roots
c) Fruits
d) Stem
Answer: a) Leaves
20. What is excreted through sweat in humans?
a) Urea
b) Water and salts
c) Glucose
d) Protein
Answer: b) Water and salts
21. In digestion, the enzyme ptyalin is found in:
a) Saliva
b) Gastric juice
c) Pancreatic juice
d) Bile juice
Answer: a) Saliva
22. Which human tooth is used for cutting food?
a) Canine
b) Incisor
c) Premolar
d) Molar
Answer: b) Incisor
23. The respiratory rate is highest in:
a) Newborn babies
b) Adults
c) Elderly people
d) Adolescents
Answer: a) Newborn babies
24. The instrument used to measure heartbeats is called:
a) Sphygmomanometer
b) Electrocardiograph
c) Stethoscope
d) Thermometer
Answer: b) Electrocardiograph
25. The pH of human blood is:
a) 4.5
b) 7.4
c) 9.2
d) 6.8
Answer: b) 7.4
26. Which gas is released during photosynthesis?
a) Carbon dioxide
b) Oxygen
c) Nitrogen
d) Hydrogen
Answer: b) Oxygen
27. In plants, photosynthesis mainly occurs in:
a) Roots
b) Stem
c) Leaves
d) Flowers
Answer: c) Leaves
28. Which acid is present in the human stomach?
a) Citric acid
b) Hydrochloric acid
c) Acetic acid
d) Lactic acid
Answer: b) Hydrochloric acid
29. In the small intestine, food is digested by:
a) Pancreatic juice
b) Bile juice
c) Intestinal juice
d) All of the above
Answer: d) All of the above
30. Deficiency of Vitamin D causes which disease?
a) Rickets
b) Scurvy
c) Beriberi
d) Night blindness
Answer: a) Rickets
31. Where does the Krebs cycle occur?
a) Cytoplasm
b) Mitochondria
c) Chloroplast
d) Nucleus
Answer: b) Mitochondria
32. In glycolysis, glucose breaks down into:
a) Pyruvic acid
b) Lactic acid
c) Ethanol
d) Acetyl Co-A
Answer: a) Pyruvic acid
33. What is the normal respiratory rate in humans?
a) 10-12 per minute
b) 12-20 per minute
c) 20-25 per minute
d) 25-30 per minute
Answer: b) 12-20 per minute
34. In respiration, energy is stored in the form of:
a) ADP
b) ATP
c) AMP
d) NADPH
Answer: b) ATP
35. In aerobic respiration, how many ATP molecules are produced from one glucose molecule?
a) 2
b) 18
c) 36
d) 38
Answer: d) 38
36. In humans, oxygenated blood is found in:
a) Pulmonary artery
b) Aorta
c) Pulmonary vein
d) Vena cava
Answer: c) Pulmonary vein
37. From which part of the heart is oxygenated blood pumped to the body?
a) Left atrium
b) Left ventricle
c) Right atrium
d) Right ventricle
Answer: b) Left ventricle
38. Which substance helps in blood clotting?
a) Hemoglobin
b) Fibrinogen
c) Globulin
d) Albumin
Answer: b) Fibrinogen
39. In plants, food is transported through:
a) Xylem
b) Phloem
c) Cambium
d) Stomata
Answer: b) Phloem
40. What is the lifespan of red blood cells (RBCs)?
a) 30 days
b) 60 days
c) 120 days
d) 180 days
Answer: c) 120 days
41. In the human kidney, urine formation occurs in:
a) Neuron
b) Nephron
c) Glomerulus
d) Loop of Henle
Answer: b) Nephron
42. Nitrogenous waste present in urine includes:
a) Uric acid
b) Urea
c) Ammonia
d) All of the above
Answer: d) All of the above
43. In plants, excretory products are stored as:
a) Gum
b) Resin
c) Tannin
d) All of the above
Answer: d) All of the above
44. What is excreted through human skin?
a) Urea
b) Sweat
c) CO₂
d) All of the above
Answer: b) Sweat
45. Blood purification in the kidneys occurs through:
a) Absorption
b) Filtration
c) Secretion
d) All of the above
Answer: d) All of the above
46. Which valve opens during swallowing in humans?
a) Cardiac valve
b) Pyloric valve
c) Epiglottis
d) None of the above
Answer: c) Epiglottis
47. Which metal is present in hemoglobin?
a) Calcium
b) Iron
c) Sodium
d) Potassium
Answer: b) Iron
48. In plants, gas exchange occurs through:
a) Stomata
b) Xylem
c) Phloem
d) Root hairs
Answer: a) Stomata
49. The longest part of the human digestive system is:
a) Esophagus
b) Stomach
c) Small intestine
d) Large intestine
Answer: c) Small intestine
50. Which valve prevents oxygenated blood from flowing back into the heart?
a) Tricuspid valve
b) Bicuspid valve
c) Semilunar valve
d) Pyloric valve
Answer: c) Semilunar valve
Additional MCQs (Previous Year Board Questions Included)
1. CBSE 2020 – Which gas is released during photosynthesis?
a) CO₂
b) O₂
c) N₂
d) H₂
Answer: b) O₂
2. MP Board 2021 – Where does digestion begin in humans?
a) Stomach
b) Mouth
c) Small intestine
d) Esophagus
Answer: b) Mouth
3. Bihar Board 2019 – Where is bile stored?
a) Liver
b) Gallbladder
c) Pancreas
d) Stomach
Answer: b) Gallbladder
4. UP Board 2022 – Which disease is caused by a deficiency of Vitamin C?
a) Night blindness
b) Scurvy
c) Beriberi
d) Rickets
Answer: b) Scurvy
5. CBSE 2021 – Through which tissue is food transported in plants?
a) Xylem
b) Phloem
c) Stomata
d) Root hair
Answer: b) Phloem
6. MP Board 2020 – Which is the main respiratory organ in humans?
a) Liver
b) Kidney
c) Lungs
d) Heart
Answer: c) Lungs
7. Bihar Board 2021 – What is the final product of aerobic respiration of glucose?
a) CO₂ + H₂O
b) CO₂ + Ethanol
c) Lactic acid
d) Pyruvic acid
Answer: a) CO₂ + H₂O
8. UP Board 2019 – Where does the Krebs cycle occur?
a) Cytoplasm
b) Mitochondria
c) Chloroplast
d) Nucleus
Answer: b) Mitochondria
9. CBSE 2022 – What is produced in anaerobic respiration?
a) Ethanol + CO₂
b) Lactic acid
c) Both (a) and (b)
d) Only H₂O
Answer: c) Both (a) and (b)
10. MP Board 2022 – In whom is the respiratory rate the highest?
a) Adults
b) Children
c) Elderly
d) Adolescents
Answer: b) Children
11. Bihar Board 2020 – Where is pure blood found in humans?
a) Aorta
b) Pulmonary vein
c) Vena cava
d) Pulmonary artery
Answer: b) Pulmonary vein
12. UP Board 2021 – From which part of the heart does impure blood go to the lungs?
a) Left ventricle
b) Right ventricle
c) Left atrium
d) Right atrium
Answer: b) Right ventricle
13. CBSE 2019 – What is the lifespan of red blood cells (RBCs)?
a) 30 days
b) 60 days
c) 120 days
d) 180 days
Answer: c) 120 days
14. MP Board 2021 – Which protein helps in blood clotting?
a) Hemoglobin
b) Fibrinogen
c) Insulin
d) Enzyme
Answer: b) Fibrinogen
15. Bihar Board 2022 – Through which tissue is water transported in plants?
a) Phloem
b) Xylem
c) Stomata
d) Cambium
Answer: b) Xylem
16. UP Board 2020 – Which is the main excretory organ in humans?
a) Liver
b) Kidney
c) Skin
d) Intestine
Answer: b) Kidney
17. CBSE 2021 – Nephron is the functional unit of which organ?
a) Heart
b) Lungs
c) Kidney
d) Liver
Answer: c) Kidney
18. MP Board 2019 – Which nitrogenous waste is present in urine?
a) Urea
b) Uric acid
c) Ammonia
d) All of the above
Answer: d) All of the above
19. Bihar Board 2021 – In what form are excretory substances stored in plants?
a) Gum
b) Resin
c) Tannin
d) All of the above
Answer: d) All of the above
20. UP Board 2022 – What is released through sweat in humans?
a) Urea
b) Water and salts
c) Glucose
d) Protein
Answer: b) Water and salts
21. CBSE 2020 – Which metal element is found in hemoglobin?
a) Calcium
b) Iron
c) Sodium
d) Potassium
Answer: b) Iron
22. MP Board 2021 – How many chambers are there in the human heart?
a) 2
b) 3
c) 4
d) 5
Answer: c) 4
23. Bihar Board 2019 – Which is the longest part of the human digestive system?
a) Esophagus
b) Stomach
c) Small intestine
d) Large intestine
Answer: c) Small intestine
24. UP Board 2020 – Through which structure do plants exchange gases?
a) Stomata
b) Xylem
c) Phloem
d) Root hair
Answer: a) Stomata
25. CBSE 2022 – Which valve opens while swallowing food in humans?
a) Cardiac
b) Pyloric
c) Epiglottis
d) None
Answer: c) Epiglottis