Life Processes Class 10 MCQ

Hello Students, how are you all, hope you all will be good, in this Page we have shared with you more than 100 Important MCQ on life processes class 10 with answers which is helpful for various entrance exams preparation. This life processes MCQ Pdf will help you enhance your performance in entrance exams.

Life processes MCQ Questions and Answers are provided here with detailed explanation of each question. These life processes Class 10 MCQ are important from the NEET as well as various type of exam like NTSE, By practicing our MCQ on life processes class 10 pdf students will get acquainted with the key concepts which must be prepared to score high marks in the objective type questions in the any exam.

100+ Life Processes Class 10 MCQ with Answers Pdf

1. Which of the following statements about autotrophs is incorrect?
A) They synthesized carbohydrates by using carbon dioxide, water in presence of sunlight and chlorophyll
B) They store carbohydrates in form of starch
C) They convert carbon dioxide and water into carbohydrates in the absence of sunlight
D) They form the first trophic level in the food chain
Answer: C
Explanation: Autotrophs require sunlight to carry out photosynthesis. Hence, C is incorrect.

Read: Plant Physiology MCQ

2. Write correct sequence of anaerobic respiration:
A) Glucose → pyruvate → lactic acid
B) Glucose → Pyruvate → Ethanol + Carbon-Dioxide
C) Glucose → pyruvate → ADP→ lactic acid
D) Glucose → pyruvate → carbon dioxide + ethanol + energy
Answer: B
Explanation: Anaerobic respiration in yeast produces ethanol and CO₂ from pyruvate.

Read: Biochemistry MCQ

3. The pancreas pour their secretion into:
A) Small intestine
B) Large intestine
C) Stomach
D) Duodenum
Answer: D
Explanation: The pancreas secretes digestive enzymes into the duodenum (first part of the small intestine).

Read: MCQ on Biodiversity

4. The kidneys in human beings are part of:
A) Nutrition
B) Respiration
C) Excretion
D) Circulation
Answer: C
Explanation: Kidneys filter nitrogenous wastes from blood – a key excretory function.

Read: MCQ on Proteins and Amino Acids 

5. Which of the following components of food is digested by amylase?
A) Proteins
B) Fats
C) Minerals
D) Carbohydrates
Answer: D
Explanation: Amylase breaks down starch (a carbohydrate) into simple sugars.

Read: MCQ on Plasmids and Vector

6. The autotrophs require:
A) CO₂ and water
B) Chlorophyll
C) Sunlight
D) All
Answer: D
Explanation: All three are essential for photosynthesis

Read: Environmental Studies MCQ

7. The correct path of urine is:
A) Kidney → ureter → urethra → urinary bladder
B) Kidney → urinary bladder → urethra → ureter
C) Kidney → ureter → urinary bladder → urethra
D) Urinary bladder → kidney → ureter → urethra
Answer: C
Explanation: Urine passes from kidneys → ureters → bladder → urethra.

Read: MCQ on Renewable and Non-Renewable Energy

8. ATP stands for:
A) Adenosine diphosphate
B) Adenosine phosphate
C) Adenosine triphosphate
D) None
Answer: C
Explanation: ATP is the energy currency of cells.

Read: MCQ on Environmental Microbiology

9. The enzymes pepsin and trypsin are secreted by:
A) Stomach and pancreas
B) Salivary gland and stomach
C) Liver and pancreas
D) Liver and salivary gland
Answer: A
Explanation: Pepsin from stomach; Trypsin from pancreas.

Read: MCQ on Pollen Grains with Answers 

10. The enzymes contained in pancreatic juices help in the digestion of:
A) Fats and carbohydrates
B) Proteins and fats
C) Proteins and carbohydrates
D) Proteins, fats, and carbohydrates
Answer: D
Explanation: Pancreatic juice contains enzymes for all major biomolecules.

Read: Ecology MCQ Questions

11. The vein which brings clean blood from the lungs into the heart is known as:
A) Pulmonary vein
B) Hepatic vein
C) Superior vena cava
D) Pulmonary artery
Answer: A
Explanation: Pulmonary vein carries oxygenated blood to the left atrium.

Read: MCQ on Male Reproductive System

12. Which among the following procedures is used for cleaning the blood of a person by separating the waste substance from it?
A) Kidney transplant
B) Blood transfusion
C) Dialysis
D) Hydrolysis
Answer: C
Explanation: Dialysis removes nitrogenous wastes from the blood in kidney failure patients.

13. Which among the following is necessary to carry out the blood coagulation in a cut or wound?
A) White Blood Cells
B) Blood plasma
C) Platelets
D) Red blood cells
Answer: C
Explanation: Platelets help in clot formation.

14. In amoeba, food is digested in the:
A) Food vacuole
B) Mitochondria
C) Pseudopodia
D) Chloroplast
Answer: A
Explanation: Amoeba digests food inside food vacuoles.

15. The contraction and expansion movement of the walls of the food pipe is called:
A) Translocation
B) Transpiration
C) Peristaltic movement
D) Digestion
Answer: C
Explanation: Peristalsis moves food through the esophagus.

16. The respiratory pigment in human beings is:
A) Carotene
B) Chlorophyll
C) Haemoglobin
D) Mitochondria
Answer: C
Explanation: Hemoglobin carries oxygen in human blood.

17. How do these fungi obtain nutrition?
A) By eating the bread on which it is growing
B) By using nutrients from the bread to prepare their own food
C) By breaking down the nutrients of bread and then absorbing them
D) By allowing other organisms to grow on the bread and then consuming them
Answer: C
Explanation: Fungi are saprotrophs—they secrete enzymes and absorb nutrients.

18. The opening and closing of the stomatal pore depends upon:
A) Oxygen
B) Temperature
C) Water in the guard cells
D) Concentration of CO₂
Answer: C
Explanation: Turgidity of guard cells (due to water) controls stomatal opening.

19. A plant gets rid of excess water through transpiration. Which is a method used by plants to get rid of solid waste products?
A) Shortening of stem
B) Dropping down of fruits
C) Shedding of yellow leaves
D) Expansion of roots into the soil
Answer: C
Explanation: Plants shed old leaves to remove waste materials.

20. Digestion of food starts from which organ of the human digestive system?
A) Mouth due to the presence of saliva
B) Oesophagus that moves the food in gut
C) That releases juices for fat breakdown
D) Which helps in mixing food with digestive juices
Answer: A
Explanation: Saliva in the mouth begins starch digestion.

21. What is the percentage of the oxygen in the expired air when a person is resting?
A) 12%
B) 16%
C) 20%
D) 24%
Answer: B
Explanation: Expired air has 16% O₂ (vs 21% in inhaled air).

22. How is food transported from phloem to the tissues according to plants’ needs?
A) Food is transported along with the water in the plant’s body
B) Food is transported in only one direction like water
C) Food is transported from a region with low concentration to higher concentration
D) Food is transported from a region where it is produced to other parts of the plants
Answer: D
Explanation: Phloem carries food from source (leaves) to sink (tissues).

23. Main site of photosynthesis:
A) Leaf
B) Stem
C) Chloroplast
D) Guard cells
Answer: C
Explanation: Chloroplasts in leaf cells are the main site of photosynthesis.

24. Which element is used in the synthesis of proteins?
A) Hydrogen
B) Oxygen
C) Nitrogen
D) Carbon dioxide
Answer: C
Explanation: Nitrogen is essential for amino acid and protein synthesis.

25. Lipase acts on:
A) Amino acids
B) Fats
C) Carbohydrates
D) All of these
Answer: B
Explanation: Lipase is an enzyme that breaks down fats.

26. One cell-thick vessels are called:
A) Arteries
B) Veins
C) Capillaries
D) Pulmonary artery
Answer: C
Explanation: Capillaries are microscopic blood vessels with walls just one cell thick to allow gas exchange.

27. Bile juice is secreted by:
A) Stomach
B) Pancreas
C) Small intestine
D) Liver
Answer: D
Explanation: Bile is produced by the liver and stored in the gallbladder.

28. Which region of the alimentary canal absorbs the digested food?
A) Stomach
B) Small intestine
C) Large intestine
D) Liver
Answer: B
Explanation: The small intestine is the main site for nutrient absorption.

29. When a few drops of iodine solution are added to rice water, the solution turns blue-black in colour. This indicates that rice water contains:
A) Fats
B) Complex proteins
C) Starch
D) Simple proteins
Answer: C
Explanation: Iodine reacts with starch to form a blue-black complex.

30. The breakdown of pyruvate to give carbon dioxide, water and energy takes place in:
A) Cytoplasm
B) Mitochondria
C) Chloroplast
D) Nucleus
Answer: B
Explanation: Pyruvate is further broken down in mitochondria during aerobic respiration.

31. Name the pores in a leaf through which respiratory exchange of gases takes place:
A) Lenticels
B) Vacuoles
C) Xylem
D) Stomata
Answer: D
Explanation: Stomata control gas exchange in leaves.

32. The respiratory pigment in human beings is:
A) Carotene
B) Chlorophyll
C) Haemoglobin
D) Mitochondria
Answer: C
Explanation: Hemoglobin in red blood cells carries oxygen.

33. Name a circulatory fluid in the human body other than blood:
A) Platelets
B) RBC
C) Lymph
D) Plasma
Answer: C
Explanation: Lymph is part of the lymphatic system and helps in immune response and fluid balance.

34. Name the tube which connects the kidneys to the urinary bladder:
A) Urethra
B) Nephron
C) Tubule
D) Ureter
Answer: D
Explanation: Ureters transport urine from kidneys to the bladder.

35. Which is the correct sequence of body parts in the human alimentary canal?
A) Mouth → stomach → small intestine → large intestine → oesophagus
B) Mouth → oesophagus → stomach → small intestine → large intestine
C) Mouth → stomach → oesophagus → small intestine → large intestine
D) Mouth → oesophagus → stomach → large intestine → small intestine
Answer: B
Explanation: This is the correct anatomical sequence for digestion.

36. ATP can be used in the cells for the:
A) Contraction of muscles
B) Protein synthesis
C) Conduction of nervous impulses
D) All of the above
Answer: D
Explanation: ATP is the universal energy currency used in various cellular functions.

37. Plasma transports __________ in dissolved form.
A) Food
B) Carbon dioxide
C) Nitrogenous wastes
D) All of the above
Answer: D
Explanation: Plasma transports various substances including nutrients and wastes.

38. The normal systolic pressure is about ____ mm of Hg and diastolic pressure is ____ mm of Hg.
A) 100, 60
B) 120, 80
C) 140, 100
D) 160, 120
Answer: B
Explanation: Normal blood pressure is 120/80 mm Hg.

39. Following is true for tissue fluid or lymph:
A) It is similar to the plasma of blood
B) It is colorless
C) It contains less protein
D) All of the above
Answer: D
Explanation: Lymph is colorless, plasma-like, and protein-poor.

40. The enzymes present in secreted intestinal juice finally convert the:
A) Proteins to amino acids
B) Complex carbohydrates into glucose
C) Fats into fatty acids and glycerol
D) All of the above
Answer: D
Explanation: Intestinal enzymes complete digestion of all macronutrients.

41. Gastric glands release ____ a protein digesting enzyme called pepsin and mucus.
A) Sulphuric acid
B) Hydrochloric acid
C) Nitric acid
D) None of the above
Answer: B
Explanation: HCl activates pepsin and helps digestion in the stomach.

42. Chlorophyll is contained in:
A) Leaf
B) Stem
C) Roots
D) Both (A) and (B)
Answer: D
Explanation: Chlorophyll is primarily in leaves but also in green stems.

43. The process of acquiring Oxygen from outside the body and using it in the breakdown of food sources for cellular needs is called:
A) Respiration
B) Digestion
C) Transportation
D) Excretion
Answer: A
Explanation: This is the definition of cellular respiration.

44. The waste products removed from the body and discarded by a process is called:
A) Respiration
B) Digestion
C) Transportation
D) Excretion
Answer: D
Explanation: Excretion removes metabolic wastes.

45. Example of some organisms that break down the food material outside the body and then absorb it:
A) Fungi
B) Yeast
C) Mushrooms
D) All of the above
Answer: D
Explanation: All are examples of saprophytic nutrition.

46. The end product of fat digestion is:
A) Fatty acid
B) Glycerol
C) Amino acids
D) Both A and B
Answer: D
Explanation: Fats are broken into fatty acids and glycerol.

47. Alternate contraction and relaxation of the alimentary canal is called:
A) Peristalsis
B) Ingestion
C) Deglutition
D) None of these
Answer: A
Explanation: Peristalsis moves food along the digestive tract.

48. Roots of the plants absorb water from the soil through the process of:
A) Diffusion
B) Transpiration
C) Osmosis
D) None of these
Answer: C
Explanation: Water enters root hairs by osmosis.

49. Which of the following events in the mouth cavity will be affected if salivary amylase is lacking in the saliva?
A) Starch breaking down into sugars
B) Proteins breaking down into amino acids
C) Absorption of vitamins
D) Fats breaking down into fatty acids and glycerol
Answer: A
Explanation: Salivary amylase digests starch in the mouth.

50. Conversion of large fat droplets into smaller droplets is:
A) Anabolism
B) Neutralisation
C) Assimilation
D) Emulsification
Answer: D
Explanation: Bile salts emulsify fats, increasing their surface area for digestion.

51. Job of maintenance function of living being is performed by:
A) Movements
B) Growth
C) Life processes
D) Reproduction
Answer: C
Explanation: Life processes like nutrition, respiration, excretion, etc., maintain living functions.

52. In simple organisms, exchange of gases and excretion occur through:
A) Osmosis
B) Diffusion
C) Imbibition
D) All the above
Answer: B
Explanation: In unicellular organisms, diffusion helps in gas exchange and excretion.

53. The carbohydrate reserve of plants is:
A) Starch
B) Glycogen
C) Fat
D) Cellulose
Answer: A
Explanation: Plants store carbohydrates as starch.

54. ATP synthesis occurs in response to:
A) Electron gradient
B) Turgor pressure gradient
C) Proton gradient
D) Negative pressure
Answer: C
Explanation: ATP is synthesized by ATP synthase in mitochondria driven by a proton gradient.

55. Number of molars that can be present in an adult human is:
A) 3
B) 6
C) 8
D) 12
Answer: D
Explanation: Adults typically have 3 molars in each quadrant = 12 total.

56. Nutrition of Amoeba is:
A) Holozoic
B) Holophytic
C) Saprophytic
D) Parasitic
Answer: A
Explanation: Amoeba ingests solid food and digests it internally—holozoic nutrition.

57. Proteolytic enzyme of pancreatic juice is:
A) Pepsin
B) Trypsin
C) Amylase
D) Lipase
Answer: B
Explanation: Trypsin breaks down proteins in the small intestine.

58. Krebs cycle operates in:
A) Endoplasmic reticulum
B) Chloroplasts
C) Golgi bodies
D) Mitochondria
Answer: D
Explanation: Krebs cycle takes place in the mitochondrial matrix.

59. Muscular partition present between thorax and abdomen is:
A) Pericardium
B) Pleura
C) Epiglottis
D) Diaphragm
Answer: D
Explanation: Diaphragm helps in breathing by separating thoracic and abdominal cavities.

60. Chemical released by blood platelets is:
A) Prothrombin
B) Heparin
C) Fibrinogen
D) Thromboplastin
Answer: D
Explanation: Thromboplastin initiates the clotting process.

61. Life span of an RBC is:
A) 40 days
B) 80 days
C) 120 days
D) 160 days
Answer: C
Explanation: Red blood cells live for around 120 days.

62. Clotting of blood does not occur inside blood vessels due to presence of:
A) Oxalic acid
B) Heparin
C) Prothrombin
D) Hirudin
Answer: B
Explanation: Heparin is an anticoagulant.

63. Contractile vacuole of Amoeba takes part in:
A) Locomotion
B) Digestion of food
C) Ingestion of food
D) Osmoregulation
Answer: D
Explanation: The contractile vacuole helps maintain water balance.

64. Anaerobic breakdown of glucose in our muscles produces:
A) Pyruvate
B) Lactic acid
C) Ethyl alcohol
D) Oxalic acid
Answer: B
Explanation: Lactic acid is formed during anaerobic respiration in muscles.

65. ATP and NADP·2H are produced in:
A) Mitochondria
B) Chloroplast
C) Peroxisomes
D) Lysosomes
Answer: A
Explanation: ATP is produced in mitochondria; but note: NADPH is made in chloroplasts during photosynthesis.
(This question may be flawed. If “NADPH” was meant instead of NADP·2H, answer should be B.)

66. Number of salivary glands found in man are:
A) One pair
B) Two pairs
C) Three pairs
D) Five pairs
Answer: C
Explanation: Humans have three pairs of salivary glands: parotid, submandibular, sublingual.

67. Rate of photosynthesis is high in:
A) Orange light
B) Green light
C) Red light
D) Yellow light
Answer: C
Explanation: Red and blue light are most effective for photosynthesis; green is least.

68. Light reaction takes place in:
A) Grana
B) Stroma
C) Mitochondria
D) Leucoplast
Answer: A
Explanation: Light-dependent reactions of photosynthesis occur in the grana of chloroplasts.

69. Excess glucose is stored in our body in the form of:
A) Glycogen
B) Fat
C) Protein
D) Cholesterol
Answer: A
Explanation: Glycogen is stored in the liver and muscles.

70. Which is the correct sequence of the air passage in man:
A) Nasal cavity → Pharynx → Larynx → Trachea → Bronchi → Alveoli
B) Nasal cavity → Larynx → Pharynx → Trachea → Bronchi → Alveoli
C) Nasal cavity → Pharynx → Trachea → Larynx → Bronchi → Alveoli
D) Nasal cavity → Trachea → Larynx → Bronchi → Alveoli
Answer: A
Explanation: This is the correct anatomical order of the respiratory pathway.

71. Number of alveoli in lungs is:
A) 30 thousand
B) 30 lac
C) 3 crore
D) 30 crore
Answer: D
Explanation: Lungs contain about 300 million (30 crore) alveoli.

72. Which blood corpuscles destroy bacteria?
A) W.B.C
B) R.B.C
C) Blood platelets
D) All these
Answer: A
Explanation: White blood cells (like neutrophils, monocytes) fight infections.

73. Glycolysis takes place in:
A) Cytoplasm
B) Chloroplast
C) Mitochondria
D) Ribosome
Answer: A
Explanation: Glycolysis occurs in the cytoplasm of all cells.

74. During aerobic respiration, one molecule of glucose produces:
A) 32 ATP
B) 19 ATP
C) 38 ATP
D) 30 ATP
Answer: C
Explanation: Complete aerobic respiration yields 38 ATP molecules (in ideal conditions).

75. Amoeba ingests food with the help of:
A) Cilia
B) Mouth
C) Flagella
D) Pseudopodia
Answer: D
Explanation: Amoeba uses pseudopodia (false feet) to engulf food.

76. Food is translocated by phloem in the form of:
A) Sucrose
B) Protein
C) Hormone
D) Fats
Answer: A
Explanation: Phloem transports sucrose (a disaccharide) from source (leaves) to sink (roots, fruits, etc.).

77. Malpighian body consists of:
A) Uriniferous tubule
B) Bowman’s capsule and glomerulus
C) Bowman’s capsule and neck
D) Two limbs of loop of Henle
Answer: B
Explanation: Malpighian body = glomerulus + Bowman’s capsule; part of nephron.

78. Muscle contraction of alimentary canal is called:
A) Digestion
B) Peristalsis
C) Circulation
D) Absorption
Answer: B
Explanation: Peristalsis moves food along the digestive tract through wave-like contractions.

79. The xylem in plants are responsible for:
A) Transport of water
B) Transport of food
C) Transport of amino acids
D) Transport of oxygen
Answer: A
Explanation: Xylem conducts water and minerals from roots to other plant parts.

80. The energy currency is:
A) DNA
B) RNA
C) ATP
D) Chlorophyll
Answer: C
Explanation: ATP (adenosine triphosphate) stores and provides energy for cell functions.

81. It is necessary to separate oxygenated blood from deoxygenated blood in mammals:
A) To maintain the body temperature
B) To provide more oxygen to cells
C) Both (a) and (b)
D) None of the above
Answer: C
Explanation: This separation helps maintain high metabolic rate and constant body temperature.

82. Who proposed the term “Homeostasis”:
A) Claude Bernard
B) Walter Cannon
C) Marcello Malpighi
D) Henle
Answer: B
Explanation: Walter Cannon coined the term homeostasis to describe body’s internal balance.

83. The chlorophyll in photosynthesis is used for:
A) Absorbing light
B) Breaking down water molecule
C) No function
D) Reduction of CO₂
Answer: A
Explanation: Chlorophyll captures light energy to drive photosynthesis.

84. Which of the following sequences is truly a systemic circulation pathway?
A) Left auricle → Left ventricle → Pulmonary aorta → Tissues → Right auricle
B) Left auricle → Left ventricle → Aorta → Arteries → Tissues → Veins → Right atrium
C) Right ventricle → Pulmonary aorta → Tissues → Pulmonary veins → Left auricle
D) Right auricle → Left ventricle → Aorta → Tissues → Veins → Right auricle
Answer: B
Explanation: This is the correct systemic circulation path in humans.

85. Which one is uricotelic?
A) Frog and toads
B) Lizards and birds
C) Cattle, monkey and man
D) Molluscs
Answer: B
Explanation: Uricotelic organisms excrete uric acid (e.g., birds and reptiles).

86. Autotrophs and heterotrophs differ in:
A) How they obtain their carbon
B) Whether they are prokaryotic or eukaryotic
C) How they reproduce, sexually or asexually
D) Whether they use chemicals or light as a source of energy
Answer: A
Explanation: Autotrophs use CO₂; heterotrophs depend on organic carbon.

87. Correct order of excretory organs in cockroach, earthworm and rabbit respectively:
A) Skin, malpighi tubules, kidney
B) Malpighi tubules, nephridia, kidney
C) Nephridia, malpighi tubules, kidney
D) Nephridia, kidney, green gland
Answer: B
Explanation: Excretory organs: cockroach – Malpighian tubules, earthworm – nephridia, rabbit – kidneys.

88. Which part of the plant helps to absorb water and minerals from the soil?
A) Root hairs
B) Roots
C) Root cap
D) Tap root
Answer: A
Explanation: Root hairs increase surface area for absorption.

89. Which of the following help in protecting the inner lining of the stomach from the harmful effect of hydrochloric acid?
A) Mucus
B) Pepsin
C) Trypsin
D) Bile
Answer: A
Explanation: Mucus lines the stomach to prevent acid damage.

90. The enzymes pepsin and trypsin are secreted by:
A) Stomach and pancreas
B) Salivary gland and stomach
C) Liver and pancreas
D) Liver and salivary gland
Answer: A
Explanation: Pepsin – stomach; trypsin – pancreas.

91. During contraction, what prevents the backflow of blood inside the heart?
A) Valves in heart
B) Thick muscular walls of ventricles
C) Thin walls of atria
D) All of the above
Answer: A
Explanation: Valves ensure unidirectional flow of blood.

92. Entities exhibiting the properties of both non-living and living are called:
A) Lichens
B) Bacteria
C) Diatoms
D) Viruses
Answer: D
Explanation: Viruses show living traits only inside host cells.

93. The chlorophyll is used in photosynthesis for:
A) No function
B) Breaking down the water molecule
C) Reduction of carbon dioxide
D) Absorbing light
Answer: D
Explanation: Light absorption initiates photosynthesis.

94. The enzymes that are found in the secreted intestinal juice finally convert:
A) Proteins to amino acids
B) Fats into fatty acids and glycerol
C) Complex carbohydrates into glucose
D) All the above
Answer: D
Explanation: Intestinal enzymes complete digestion of all biomolecules.

95. Reduction of blood pH will:
A) Reduce blood supply to brain
B) Reduce heartbeat rate
C) Decrease haemoglobin affinity with oxygen
D) Release bicarbonate ions by liver
Answer: C
Explanation: Acidosis lowers hemoglobin’s affinity for oxygen.

96. Pick the correct one from the following:
A) Plasma = Blood – Lymphocytes
B) Lymph = Plasma + RBC + WBC
C) Serum = Blood + Fibrinogen
D) Blood = Plasma + RBC + WBC
Answer: D
Explanation: Blood consists of plasma and blood cells.

97. Choose the function of the pancreatic juice from the following:
A) Trypsin digests proteins and lipase carbohydrates
B) Trypsin digests emulsified fats and lipase proteins
C) Trypsin and lipase digest fats
D) Trypsin digests proteins and lipase emulsified fats
Answer: D
Explanation: Pancreatic juice: trypsin → proteins; lipase → fats.

98. Which of the following is an incorrect statement?
A) Organisms grow with time
B) Organisms must repair and maintain their structure
C) Movement of molecules does not take place among cells
D) Energy is essential for life processes
Answer: C
Explanation: Molecule movement between cells is essential for homeostasis.

99. The filtration units of kidneys are called:
A) Urethra
B) Ureter
C) Neurons
D) Nephrons
Answer: D
Explanation: Nephrons filter blood and form urine.

100. Oxygen liberated during photosynthesis comes from:
A) Water
B) Chlorophyll
C) Carbon dioxide
D) Glucose
Answer: A
Explanation: Water splitting (photolysis) during light reaction releases O₂.