Comprehensive Biology Test 15

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Science & Biology (Vitamins, Human Body, Plants, Chemistry)

1. 
   
   
   
   1. Which vitamin is essential for vision ? – Vitamin A
      Explanation: Vitamin A is necessary for proper functioning of the retina; deficiency leads to night blindness.
   
   
   2. Which vitamin is essential for blood clotting ? – Vitamin K
      Explanation: Vitamin K helps in the production of prothrombin, which is necessary for blood clotting.
   
   
   3. Deficiency of vitamin D causes which disease ? – Rickets
      Explanation: Weakens bones in children, causing deformities due to poor calcium absorption.
   
   
   4. Deficiency of vitamin B1 causes which disease ? – Beriberi
      Explanation: Affects the nervous system and heart; caused by lack of thiamine.
   
   
   5. Deficiency of vitamin B3 causes which disease ? – Pellagra
      Explanation: Causes dermatitis, diarrhea, and mental confusion; due to lack of niacin.
   
   
   6. Deficiency of iron causes which disease ? – Anaemia
      Explanation: Low hemoglobin reduces oxygen transport, causing fatigue and weakness.
   
   
   7. Which gas is used in food preservation ? – Carbon dioxide (CO₂)
      Explanation: CO₂ prevents microbial growth in packaged and carbonated foods.
   
   
   8. Who discovered penicillin? – Alexander Fleming
      Explanation: First antibiotic discovered in 1928, used to treat bacterial infections.
   
   
   9. Which is the smallest bone in human body ? – Stapes
      Explanation: Found in the middle ear, transmits sound vibrations to inner ear.
   
   
   10. Largest gland in human body ? – Liver
       Explanation: Performs digestion, detoxification, and stores nutrients.
   
   
   11. Which disease is caused by vitamin C deficiency ? – Scurvy
       Explanation: Causes bleeding gums, weakness, and anemia due to lack of Vitamin C.
   
   
   12. Where are red blood cells made ? – Bone marrow
       Explanation: Bone marrow produces RBCs which transport oxygen in the body.
   
   
   13. Which vitamin is produced by sunlight ? – Vitamin D
       Explanation: Skin synthesizes vitamin D when exposed to UV rays; essential for bones.
   
   
   14. The study of plants is called ? – Botany
       Explanation: Botany deals with plant structure, growth, reproduction, and classification.
   
   
   15. H₂O is commonly known as? – Water
       Explanation: Composed of two hydrogen and one oxygen atom; essential for life.