Fig. 4From: Effects of copper and cadmium on development and superoxide dismutase levels in horseshoe crab (Limulus polyphemus) embryosRelative amount of Mn SOD protein in Stage 20 Limulus polyphemus embryos exposed to Cu as determined by Western blotting. Data expressed as the mean ratio (±SE) of Mn SOD in exposed animals relative to seawater controls (n = 2–4 replicate determinations). a 4 h, b 8 h, c 16 h, and d 24 h acute exposure to CuBack to article page