The answer is guard cells.
Guard cells are cells surrounding each stoma. They help regulate the rate of transpiration by opening and closing the stomata. They are specialized cells in the epidermis of leaves, stems and other organs that are used to control gas exchange. They are produced in pairs with a gap between them that forms a stomatal pore (stoma).
Answer:
I think this would help you Sun, water, food, animals, etc.
They act like convey belt, transporting water the both sides of the pole
Answer:
When acid rain falls on the marble stone, it dissolve calcium when the acid present in the rain water react with the calcium of the marble stone.
Explanation:
Acid rain is formed when gases such as carbondioxode and sulfur dioxide etc that is emitted from vehicles and industries goes to the atmosphere and react with the water present in the form of clouds and formed the water acidic. When this water comes down to the earth, it damage many materials due to acid present in it.
