Water
Case of the Drought Resistant Genetically Engineered Corn Plant
This scenario accompanies the online lesson, "Transpiration - Water Movement Through Plants", and is designed to allow you to apply the concepts learned in that lesson to a real-life problem.
Greening Up the Greens - Transpiration Application Scenario
A scenario to accompany the online lesson, 'Transpiration - Water Movement Through Plants'.
Root Absorption and Xylem Translocation
Herbicides must be absorbed into plants in order to be effective. Plant roots and below ground shoots have few barriers to herbicide absorption; however, interactions with soil particles and soil organic matter have significant impacts on the amount of herbicide available for plant absorption. Plant roots and below ground shoots (hypocotyls or coleoptiles) are lipophilic by nature and do not have thick, waxy cuticles like leaves. Lipophilic and hydrophilic herbicides reach the root surface by bulk transport in soil water; however, there are a few examples of herbicides that reach the root as a vapor or gas. Soil-applied herbicides can translocate to the shoot or remain in the root system. Soil-applied herbicides translocate to the shoot in the xylem and tend to accumulate in mature leaves that transpire the most water. The lipophilic/hydrophilic nature of the herbicide will determine if the herbicide translocates to the shoot. Absorption and translocation of phloem-mobile herbicides will be discussed in another lesson.
Transpiration - Water Movement through Plants
This lesson and its animation follows the journey of water through a plant from its uptake by roots to its evaporation from the leaf surface. How this journey is altered by plant characteristics such as stomata and cuticles as well as by changes in the environment will be described.
La Transpiración - Movimiento del Agua a Través de las Plantas
La transpiración es la pérdida de agua en forma de vapor por las plantas. El agua es absorbida del suelo por las raíces y transportada en forma líquida por el xilema hacia las hojas. En las hojas, unos pequeños poros permiten que el agua (H2O) escape a la atmósfera en forma de vapor, al tiempo que se permite la entrada de bióxido de carbono (CO2) para la fotosíntesis. De toda el agua absorbida por las plantas, menos del 5% es retenida y utilizada para crecimiento y almacenamiento. En esta lección se explicará porque las plantas pierden tanta agua, la ruta que ésta sigue dentro de la planta, como pudieran las plantas controlar la pérdida excesiva de agua y como las condiciones ambientales influyen en la pérdida de agua por las plantas.