Question

The shape of guard cell changes due to change in the

• A. Protein composition of cells
• B. Temperature of cells
• C. Amount of water in cells
• D. Position of nucleus in the cells

Answer 1

Answer: (C)

Amount of water in cells

• Guard cells are cells surrounding each stoma(is a pore, found especially in the epidermis of leaves). They help to regulate the rate of transpiration by opening and closing the stomata.
• The guard cells will swell (become turgid) when water flows into them, causing the stomatal pore to open. Similarly, when guard cells shrink or become flaccid due to loss of water from them the stomatal pore closes. Hence, the shape of guard cells change due to change in the amount of water in them.
  
• So, the correct answer is 'Amount of water in cells'.