Question

what colour are onion cells before they are stained with iodine and after they are stained with iodine

Answer 1

Before:colourless,After:purple colour

Explanation:

• Before adding iodine to the onion cell they are colourless,but after adding iodine some parts of the cell absorb the iodine and turns into purple.
• The iodine is mainly added to carefully differentiate and observe the cell under microscope