Answer:
The foaming in the elephant toothpaste demonstration means that a gas is produced. Production of a gas is a clue that a chemical reaction has occurred. The water vapor in the genie-in-a-bottle demonstration also shows the production of a gas.
Guard cell o is ordered to opening and closing of stomata.
Walls are thin.
Inner surface is moist.
Tissues are filled with blood vessels.
Exposed to air
Explanation:
Correct answer is A
