Question

Why is cfu more applicable to a culture of streptococcus than to a culture of
e. coli?

Answer 1

CFU is more applicable to a culture of Streptococcus than to a culture of E. coli due to the differences in their growth characteristics and colony morphology. Streptococcus species form distinct colonies that can be easily counted, while E. coli colonies tend to merge and form a lawn.

Step-by-step explanation:

The CFU (colony-forming unit) is a measure used in microbiology to estimate the number of viable bacteria or fungal cells in a sample. CFU is more applicable to a culture of Streptococcus than to a culture of E. coli because of the differences in their growth characteristics and colony morphology.

Streptococcus species, such as Streptococcus pyogenes, form distinct colonies when grown on agar plates. These colonies can be easily counted and used to estimate the number of viable cells in the culture. In contrast, E. coli colonies tend to merge and form a lawn, making it difficult to accurately count individual colonies.

Additionally, Streptococcus species are often found in lower numbers in culture samples compared to E. coli. The CFU range of 30-300 is suitable for counting Streptococcus colonies, as it allows for a statistically reliable count without the occurrence of multiple bacterial cells forming a single colony.

Answer 2

The reason for it is because the cfu is more applicable to the culture of streptococcus because it is more susceptible in which the culture is likable or does not resist the organism in which the e. coli might be resistant with the culture, that is why it is not applicable.