apoplast
Sign in to savethumb|300px|The apoplastic and symplastic pathways The apoplast is the network of cell walls, intercellular spaces, and xylem vessels in plants that allows the movement of water, ions, and small molecules outside the plasma membrane. It forms a continuous extracellular pathway, distinct from the symplast, which involves cytoplasmic transport through plasmodesmata. Water and solutes moving via the apoplast bypass the selective control of the plasma membrane, allowing rapid bulk flow across tissues.
Article
8 sectionsContents
- Passive transport in the apoplast
- History
- Apoplastic transport
- Apoplastic colonization
- See also
- Notes
- References
- Footnotes
thumb|300px|The apoplastic and symplastic pathways The apoplast is the network of cell walls, intercellular spaces, and xylem vessels in plants that allows the movement of water, ions, and small molecules outside the plasma membrane. It forms a continuous extracellular pathway, distinct from the symplast, which involves cytoplasmic transport through plasmodesmata. Water and solutes moving via the apoplast bypass the selective control of the plasma membrane, allowing rapid bulk flow across tissues.
The apoplast provides a low-resistance pathway for water to move from roots to leaves, complementing the symplastic route. Minerals dissolved in water can travel through the apoplast until they reach the endodermis, where the Casparian strip forces selective uptake into the symplast.