Table 1.
Elastic Modulus E of the four virtual cell wall layers L1–4 inferred from the force curves obtained by atomic force microscopy.
| Cell type | A | E | I | R | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sample size | n = 6 cells | n = 7 cells | n = 2 cells | n = 4 cells | ||||||||||||
| E (MPa) | L4 | L3 | L2 | L1 | L4 | L3 | L2 | L1 | L4 | L3 | L2 | L1 | L4 | L3 | L2 | L1 |
| Mean | 3.84 | 2.48 | 1.43 | 0.46 | 7.72 | 4.23 | 1.99 | 0.24 | 18.91 | 7.29 | 3.11 | 0.54 | 16.88 | 2.77 | 0.60 | 0.21 |
| S.D. | 0.54 | 0.24 | 0.36 | 0.35 | 2.33 | 1.19 | 0.75 | 0.17 | 4.12 | 1.47 | 2.05 | 0.10 | 4.81 | 1.54 | 0.34 | 0.13 |
| Thickness (nm) | 0–83 | 83–176 | 176–264 | 264–345 | 0–69 | 69–147 | 147–217 | 217–286 | 0–41 | 41–92 | 92–155 | 155–219 | 0–55 | 55–129 | 129–261 | 261-404 |
For each cell, the force curve was optimally discretised into four linear parts. For each of the four cell wall layers, the mean (MPa) and SD are indicated, as well as the position (z-axis, or thickness) of the layer boundaries. L1 is the most external layer (i.e. the oldest), L4 the most internal one (i.e. the most recent).