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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?
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Biology: Life on Earth with Physiology (11th Edition)
- Mycoplasmas are pleomorphic bacteria. How do the unique structural characteristics of mycoplasmas relate to their bacterial morphology? Mycoplasmas have a low G + C genome content. Mycoplasmas appear Gram negative when a Gram stain is performed. Mycoplasmas lack a cell wall. Mycoplasmas form colonies with a fried-egg appearance.arrow_forwardYou are a physician working in a hospital. Your patient is a 65-year-old individual who has been living on the street. Their symptoms include trouble breathing, weakness, and most recently coughing up blood. When gram stained, the bacterium shows no color and most of the antibiotics are not reducing the infection. After reviewing the information from the last physician, you prescribe Isoniazid. Select all of the answers that are correct. Mycolic acid is present in fungal cells Mycolic acid is a waxy substance that can repel many molecules An organism that has mycolic acid has to have access to oxygen and grows very slowly. If there is not gram stain then there is no bacteria present Isonazid targets and destroys mycolic acid. ►arrow_forwardWhy is the fact that Pseudomonas species can grow in nutrient-poorenvironments medically important?arrow_forward
- Propionibacterium acnes is a normal member of the skin microbiome that benefits the body by lowering the skin's pH- an antimicrobial effect. However, P. acnes is also the leading cause of acne. Explain mechanistically how can a bacterium be normal and beneficial but also be pathogenic?arrow_forwardA dessert chef with a staphylococcal skin infection contaminates his whipped cream with bacteria. In 6 hours, the number of bacteria increases from 450 to 192,000. What is the generation time for this bacteriumarrow_forwardMycoplasmas are bacteria that lack cell walls. On the basis of this structural feature, which statement concerning mycoplasmas should be true? They are gram-negative. They are subject to lysis in hypotonic conditions. They lack a cell membrane as well. They should contain less cellulose than do bacteria that possess cell walls. They possess typical prokaryotic flagella.arrow_forward
- Which of the following diseases is NOT associated with bacteria that form endospores? tetanus anthrax toxic shock syndrome botulism gangrenearrow_forwardDescribe the appearance of an S. agalactiae colony grown on blood agar. Describe how that colony would differ in appearance from a colony of S. pyogenes.arrow_forwardThis bacteria is commonly found in soil and water, and can cause otitis externa (aka swimmers ear). Pseudomonas aeruginosa Streptococcus pyogenes Staphylococcus aureus Staphylococcus epidermidisarrow_forward
- 20. Bacterial spores function in bacterial reproduction . a) Trueb) Falsearrow_forwardBacteria can best survive low pH and dryness by producing ____________. Group of answer choices Endospores Capsules Endotoxin Cytotoxinsarrow_forwardDo you think Rickettsia rickettsii can grow on blood agar? Explain.arrow_forward
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