Figure 4

Acid and alkaline treatment cell morphology. (A) NPCD cells at 0 h for the 12 M HCl treatment. (B) NPCD cells at cell death after the 12 M HCl treatment. Nuclear condensation was evident. PM retraction was observed. Anthocyanin colouration remains, although a slight colour change occurs. (C) NPCD cells at 0 h for the 3 mM HCl treatment. (D) NPCD cells after death induced by 3 mM HCl. Anthocyanin disappearance occurs throughout treatment. (E) NPCD cells at 0 h for the 30 mM NaOH treatment. (F) NPCD cells at cell death for the 30 mM NaOH treatment. No retraction of the PM occurs. Note the swollen and ‘wrinkled’ appearance of the chloroplasts. (G) NPCD cells at 0 h for the 1 M NaOH treatment. (H) NPCD cells after death for the 1 M NaOH treatment. No PM retraction occurs. Note the swollen and ‘wrinkled’ appearance of the chloroplasts. (A-H) N– nucleus, C– chloroplast, Va– vacuole, Ve– vesicle, white arrow– tonoplast, black arrow– PM. Scale bars: A-H = 25 μm.