00490pamaa2200145 4500 0000019249 20070914090000.0 0697278751 577.8 JOH 1996 QH440.4 JOH 1996 Johnson How scientists think : twenty-one experiments that have shaped our understanding of genetics and molecular biology George B. Johnson. Iowa: Wm. C. Brown Pub., 1996. x, 93p.: 28cm. Molecular genetics -- Experiments