typical labeled sketch of a bacterial growth curve in batch culture

The proteobacteria in the genus Pseudomonas are important spoilers of food. The rate at which food spoils is dependent on temperature. The data in the Figure show the relationship between the square root of the growth rate (how fast the population is growing per day; unitless) and the temperature of the culture. Does typical refrigeration (temperature lowered to 4C) appear sufficient to limit growth rate compared to room temperature (20C)?

Yeast is a facultative anaerobe. This means that alcohol fermentation takes place only if: the temperature is close to 37°C the atmosphere does not contain oxygen sugar is provided to the cells light is provided to the cells

Researchers have discovered that washing spinach with water several times does not prevent foodborne diseases due to E. coli. How can you explain this fact?

Halophiles are organisms that require a salt concentration of at least 0.2 M high sugar concentration the addition of halogens all of the above

Many of the first prokaryotes to be cultured in a scientific lab were human or animal pathogens. Why would these species he more readily cultured than non-pathogenic prokaryotes? Pathogenic prokaryotes are hardier than non-pathogenic prokaryotes Non-pathogenic prokaryotes require more supplements in their growth media Most of the necessary culture conditions could be inferred for pathogenic prokaryotes Pathogenic bacteria can grow as free bacteria, but non-pathogenic bacteria only grow as parts of large colonies.

Prokaryotes stain as Gram-positive or Gramnegative because of differences in the cell wall cytoplasm nucleus chromosome

Figure 22.8 Compared to free-floating bacteria, bacteria in biofilms often show increased resistance to antibiotics and detergents. Why do you think this might be the case?

Prokaryotes stain as Gram-positive or Gram-negative because of differences in the_______. a. cell wall b. cytoplasm c. nucleus d. chromosome