Tag: translocation of organic solutes

• Negative hydrostatic pressure develops at the time of water loss, it occurs when the water is lost through transpiration and creates tension in the cell.
• Transpiration is the process in which water is lost through the upper or aerial plant parts in the form of water. 
• Imbibition is the swelling of cells that occurs due to the absorption of water. 
• Positive pressure is the force in the xylem which exudates drops of liquids through the stoma to the outside and also requires hydathodes which help in the process of guttation (exudation of water droplets mostly from the leaves margins). 
  

Food from the leaves is conducted downwards through the phloem in the stem.conduction of water through the xylem occurs generally upwards.

Xylem transports and stores water and water-soluble nutrients in vascular plants. Phloem is responsible for transporting sugars, proteins, and other organic molecules in plants.

Water and salt travel upwards mainly in the xylem and food substances travel up and down in the phloem.

Leaf has epidermis on both of its surfaces. The photosynthetic tissue of a leaf is sandwiched between its upper and lower epidermis and is well supplied by the vascular system. In a leaf, xylem always faces the upper epidermis i.e. the adaxial side while phloem faces both upper as well as lower epidermis.