Fig. 7.

Concentrating effect of P on solution of dextran too large to move through cell wall. (A) 580-kDa FITC-dextran (green) has Stokes' diameter of 27 nm and is pushed into the wall lumen by mineral oil (black in lumen) at low P of 0.05 MPa. Dextran is a thick layer of 45 μm adjacent to the inner wall face (measured in white box). Wall is stained with Congo Red. Scale bar = 0.5 mm. (B) Same cell after 15 min at high P of 0.5 MPa. Dextran is concentrated in a thin layer (23 μm) adjacent to the inner wall face. No dextran moved through the wall for 5 h.