exodermis
Sign in to saveThe exodermis is a physiological barrier that has a role in root function and protection. The exodermis is a membrane of variable permeability responsible for the radial flow of water, ions, and nutrients. It is the outer layer of a plant's cortex. The exodermis serves a double function as it can protect the root from invasion by foreign pathogens and ensures that the plant does not lose too much water through diffusion through the root system and can properly replenish its stores at an appropriate rate.
Article
6 sectionsContents
- Overview and function
- Growth and structure
- Passage cells
- Changes in response to external stimuli
- Xanthone synthesis
- References
The exodermis is a physiological barrier that has a role in root function and protection. The exodermis is a membrane of variable permeability responsible for the radial flow of water, ions, and nutrients. It is the outer layer of a plant's cortex. The exodermis serves a double function as it can protect the root from invasion by foreign pathogens and ensures that the plant does not lose too much water through diffusion through the root system and can properly replenish its stores at an appropriate rate.
== Overview and function == The exodermis is a specialized type of hypodermis that develops Casparian strips in its cell wall, as well as further wall modifications. The Casparian strip is a band of hydrophobic, corky-like tissue that is found on the outside of the endodermis and the exodermis. Its main function is to prevent solution backflow into the cortex and to maintain root pressure. It is also involved in ensuring that soil is not pulled directly into the root system during nutrient uptake.