
Concept explainers
To explain: The advantages of using A reading rather than percentage T as a means of estimating microbial growth.
Introduction: The microbial growth is defined as the cell division that produces two identical daughter cells, which is called binary fission of multiplication. The bacteria need a suitable environment for growth and division. Under laboratory conditions, the growth intensity of the bacteria can be measured by the spectrophotometer.

Explanation of Solution
The spectrophotometer is a monochromator instrument that uses a light beam to measure the intensity of the liquid by passing the light and the amount of light leaves the sample. The spectrophotometer can be to determine the turbidity of the media to determine the growth of the bacteria. During spectrophotometer, the cell suspension expresses absorbance (A), the amount of light it absorbs and do not express percentage (T). This is due to absorbance (A) is directly proportional to cell concentration, while the percentage is inversely proportional. When the concentration of the turbidity increases, the absorbance also increases, while the percentage decreases. Hence, absorbance has advantages in estimating microbial growth.
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Chapter 4 Solutions
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