Concept explainers
Unwelcome Dinner Guests
A few of the bacteria that commonly cause foodborne illness form endospores . For example, Bacillus cereus. a bacterial species that includes strains that cause vomiting or diarrhea in people unlucky enough to consume them, forms endospores that are widespread in soil and dust. If some spores find their way into warm, moist food, they can develop and give rise to a thriving population of bacteria. B. cereus spores are somewhat resistant to heat, but fortunately for us, they can be destroyed by thorough cooking
Although it is unsurprising that prokaryotes might thrive amidst the energy-rich substances that make up human food, our foodstuffs are hardly the only environment in which prokaryotes flourish. What are some of the more extreme environments in which bacteria and archaea can be found?
Want to see the full answer?
Check out a sample textbook solutionChapter 20 Solutions
Biology: Life on Earth with Physiology (11th Edition)
- In August 2021, there was a multi-state outbreak of melioidosis, an infectious disease caused by the bacterium Burkholderia pseudomallei, thought to arise from imported products. Burkholderia pseudomallei can be grown in culture. In terms of human health, why might it be critical to grow a pure culture of bacteria?arrow_forwardEndospores : A. are a dormant form of a bacterium AND are formed by members of medically relevant groups of bacteria. B. are a form of reproduction AND are formed by members of medically relevant groups of bacteria. C. are a dormant form of a bacterium AND are involved in anaerobic respiration. D. are formed by members of medically relevant groups of bacteria AND are involved in anaerobic respiration.arrow_forwardConsidering what you know about molds and yeasts, why do you think that we do not use the same nutrient agar used for bacteria to grow yeasts and moldsarrow_forward
- An apple pie has 3 million bacterial cells. The crust might have been inoculated with 500 bacterium. If the pie was made 6 hours ago, how many generations have happenedarrow_forwardWhich of the following statement about normal flora is INCORRECT? Question 3 options: A On Sabouraud's agar, yeast will appear as small creamy colonies and mold will have large fuzzy colonies B Alpha and gamma hemolysis is produced by Streptococcus species C Normal flora never cause disease D A healthy person can carry pathogens like MRSA and Proprionibacterium acnes on our skin E The growth of S. aureus turns the color of MSA to yellowarrow_forwardEndospores are a) resistant to extreme temperatures b) produced by some prokaryotes c) can survive for decades d) all of the abovearrow_forward
- A certain species of bacterium was grown with either glucose or sucrose as a carbon source. After a period of incubation, the number of cells (x106) was determined. Is there a difference in growth rate of the bacterium between the two carbon sources? Glucose Sucrose 6.3 5.8 5.7 6.2 6.8 6.0 6.1 5.1 5.2 5.8arrow_forwardWhich of the following is not consistent with an endospore? a. It is not a means of asexual reproduction b. Considered as a virulence factor thereby increasing the bacteria's survival c. This structure makes the bacteria withstand harsh conditions in the environment d. It is presence increases bacterial susceptibility to disinfectants and radiationarrow_forwardA bacterium has the following characteristics: I. It adheres to the human intestinal lining using a feature that protects it from phagocytes , bacteriophages, and dehydration. II. It can survive being boiled. III. It contains no plasmids and relatively little peptidoglycan. Which of the following characteristics allows this bacteria to survive in a human who is taking penicillin pills? A. gram-negative cell wall B. peptidoglycan in the cell wall C. lipopolysaccharides in the cytoplasm D. long polypeptides in the cell wallarrow_forward
- Some bacteria have a tube which allows materials to move directly into or out of the cytoplasm. This tube is called a ___. cilium flagellum genera pilusarrow_forwardLead is a very toxic metal that is not easily degraded in the environment. Lead pipes, paint containing lead, car batteries, and even lead fishing sinkers are all potential sources for the release of lead into the environment. what possible strategy can be done for identifying bacteria that may play a role in degrading lead?arrow_forwardMost bacteria require a water activity of 0.9 or higher to grow. A prolonged period of being dry usually causes loss of viability. How were there still living bacteria in many of the dried foods such as dried rice, dehydrated coconut flakes, raisins, etc.? Discuss.arrow_forward
- Biology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage LearningBiology Today and Tomorrow without Physiology (Mi...BiologyISBN:9781305117396Author:Cecie Starr, Christine Evers, Lisa StarrPublisher:Cengage Learning