Synthetic teaching example. Three biological units per condition measured repeatedly at 0, 10, 20, 40 and 60 min. Dots and lines retain actual numeric time spacing. Each line connects a contiguous observed segment within one unit; two interior missing values remain blank in source data and break those lines. Facets use shared y scales. Descriptive display; no inferential test. Each facet plot area: 50 x 50 mm; the export includes labels at their original font sizes.