Figure 2.

Left-Right Asymmetry Manifests Early in Leaf Development.

(A) and (B) Serial sections through the SAM in which the P2 center of mass is displaced in an ascending (A) or descending (B) direction. Superimposed micrographs are denoted as proximal (green), middle (cyan), and distal (black) relative to P2. M, meristem.

(C) and (D) Same images as in (A) and (B), respectively, except zoomed in and annotation removed to better visualize displacement of the P2.

(C) Of the 34 SAMs analyzed in this manner, there was no significant deviation from a 1:1 ratio of phyllotactic directions. However, P2 was significantly biased to shift in an ascending direction, assuming equal probability of ascending and descending shifts.