A flower placed in highlighter fluid will absorb the fluorescent ink into its leaves and petals. Shining a black light onto it reveals a delicate network of glowing blue veins.
How do plants move water?
Like all living things, flowers need water for metabolism. Water travels up small vascular tubes called xylem, which are located along the entire length of the plant. These tubes transport water, mineral ions, and in this case, fluorescent dye, through the transpiration-cohesion-tension theory.
Water is a polar molecule. Individual molecules are able to form hydrogen bonds with each other. In other words, water is cohesive and sticks to itself. This phenomena is also responsible surface tension.
Additionally, water can form adhesive bonds to the cellulose walls of the xylem tube. This helps it move up the xylem tube.
When a plant transpires in its leaves, as is necessary for photosynthesis, it releases water. When the water is lost from the leaf, more water from the xylem moves up to replace it. Water is absorbed from the roots to ensure a constant flow and supply. The process can be compared to drinking with a straw.
Adhesive and cohesive forces between the water and the xylem assist the water move from root to leaf in what is known as a transpiration stream.