Bay mud manifests low shear strength, high compressibility and low permeability, making it hazardous to build upon in seismically active regions like the San Francisco Bay Area. Typical bulk density of bay mud is approximately 1.3 grams per cubic centimetre.
Organisms which ferment lactose produce acid end-products which react with the pH indicator neutral red, and produce a pink color. Quadrant 1: Growth on the plate indicates the organism, Enterobacter aerogenes, is not inhibited by bile salts and crystal violet and is a gram-negative bacterium.The pink color of the bacterial growth indicates E. aerogenes is able to ferment lactose.ack to Tutorial. Quadrant 2: Growth on the plate indicates the organism, Escherichia coli, is not inhibited by bile salts and crystal violet and is a gram-negative bacterium. The pink color of the bacterial growth indicates E. coli is able to ferment lactose.
Enteric bacteria that have the ability to ferment lactose can be detected using the carbohydrate lactose, and the pH indicator neutral red. MacConkey agar is one of the most common agar plates found in a clinical microbiology lab.sing neutral red pH indicator, the agar distinguishes those Gram-negative bacteria that can ferment the sugar lactose (Lac+) from those that cannot (Lac-). This medium is also known as an indicator medium and a low selective medium. Presence of bile salts inhibits swarming by Proteus species.