Spread plate examples

The culture on this plate was not fully absorbed, causing the lines of bacteria colonies. This makes it difficult to pick an isolated, single colony.
This plate was spread with the substrate X-gal. However, it was not evenly distributed around the edge of the plate. Note that the center colonies are blue but the ones on the outside appear white.
An enlargement of the plate above, showing the outer colonies. On this plate, it would be difficult to tell if the white reprsented the desired colony or just a lack of the X-gal substrate.
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