President Barack Obama (D-IL) won the popular vote in 26 states and the District of Columbia (denoted in blue) to capture 332 electoral votes. Former Governor Mitt Romney (R-MA) won the popular vote in 24 states (denoted in red) to capture 206 electoral votes.
Xylem consists of three different types of cells: Xylem parenchyma cells and xylem fiber cells, which simply provide structural support for the most important xylem cells, the tracheary elements (TE). The TE are completely dead at maturity, and act like pipes to allow water and dissolved minterals to flow through them. There are two types of tracheary elements: vessel elements and tracheids. Though they have some structural differences, these two types function in the same manner.
The presence of vessels is a characteristic feature of flowering plants. Structure Xylem vessels are a long straight chain made of tough long dead cells known as vessel elements. The vessel have no cytoplasm. They are not living, but are made by living cells. The cells are arranged end to end and the cell walls have disappeared. This makes a tube. Vessels are made of a substance called lignin.