Most people think the plant roots they see sticking out of the ground, or just under the ground, are the roots supplying the plant with food and water. These roots are only there to keep the plant in the ground. The bigger the plant (eg. a tall tree) the bigger, deeper and wider will the big roots go to hold that tree upright in the ground.
The grey leaves on plants are covered in small upright hairs that trap moisture next to the leaf thereby reducing the amount of water the leaf looses. A leaf will evaporate water from its surface as it gets swept by any breeze, which sucks the wate