Respuesta :
Xylem
Explanation:
The flow of water through the xylem is driven by the evaporation of water from the leaves
- The xylem of a plant is the system of tubes and transport cells that circulates water and dissolved minerals
- Water flows more efficiently through some parts of the plant than others
- Water absorbed by roots must cross several cell layers before entering the specialized water transport tissue referred to as xylem
- These cell layers act as a filtration system in the root and have a much greater resistance to water flow than the xylem, where transport occurs in open tubes
- Once in the xylem tissue, water moves easily over long distances in these open tubes
- There are two kinds of conducting elements (i.e., transport tubes) found in the xylem: 1) tracheids and 2) vessels
- Tracheids are smaller than vessels in both diameter and length, and taper at each end, vessels consist of individual cells or vessel elements stacked end-to-end to form continuous open tubes
- Water movement is passively driven by pressure and chemical potential gradients
- The bulk of water absorbed and transported through plants is moved by negative pressure generated by the evaporation of water from the leaves (transpiration)
