Question

Raphides are formed of

• A. Calcium oxalate
• B. Calcium carbonate
• C. Sodium chloride
• D. Sodium carbonate

Answer 1

The correct option is A Calcium oxalate

• Minerals crystals are found in plant cell walls in the form of calcium oxalate, carbonate or silica.
  
• Calcium oxalate occurs in the form of a mass of crystals around a cellulosic core in few plants.
  
• Calcium oxalate crystals occur in the form of needle-shaped in few plant cells and are called raphides.
  
• Eg- Water hyacinth.
  
• So, the correct answer is 'Calcium oxalate'.