Figure 2.

Location and size of dissections for colon mapping. (A) Cleaned and pinned colon showing the entire colonic length. Colon length varied from 68 to 79 mm. (B–D) The colon was dissected into the sizes and locations shown to maintain uniformity for quantitative measurements. Each colon piece is numbered in the upper right corner of each box. These numbers are used to identify where samples came from for each subsequent Figure where appropriate. Each scheme is numbered starting at the same proximal colon oral site. Each set starts with the number 1 because it indicates that all 3 sectioning schemes start from the same place and show how many sections were taken in each scheme. The long section in scheme B comprises numbers 1 and 2 from scheme C and numbers 1, 2, and 3 from scheme D. The subsections in schemes C and D are smaller portions of the total region shown in scheme B. In scheme C, section 1 from scheme B is divided into 2 section, and in scheme D, it is divided into thirds.