- Created by: georgiemountford
- Created on: 16-09-19 11:31
ACROSS THE ROOT -
- Root hair cell absorbs water and mineral ions from soil.
- Water moves by osmosis across root cortex down WPG to the endodermis of the vascular bundle.
- Water may move by apoplast pathway as far as the endodermis.
- Casparian s trip blocks apoplast pathway between cortex and medulla, so water and dissolved ions have to pass through plasma membranes (symplast pathway).
- Transporter proteins in plasma membranes actively pump mineral ions into medulla and xylem so their water potential decreases. Water moves into the medulla and xylem by osmosis.
- Water cannot pass back into the cortex…