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Many of the bacteria responsive for foodborne illnesses do their damage by producing toxins. For example, different populations of the bacterial species Escherichia coli may differ genetically and some genetic differences can transform this normally harmless inhabitant of the human
Bacteria are responsible for most foodborne illnesses. But besides bacteria, which other infectious agents can wreak havoc on the human body?
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Biology: Life on Earth with Physiology (11th Edition)
- There have been recurring cases of mad-cow disease in the United Kingdom since the mid-1990s. Mad-cow disease is caused by a prion, an infectious particle that consists only of protein. In 1986, the media began reporting that cows all over England were dying from a mysterious disease. Initially, there was little interest in determining whether humans could be affected. For 10 years, the British government maintained that this unusual disease could not be transmitted to humans. However, in March 1996, the government did an about-face and announced that bovine spongiform encephalopathy (BSE), commonly known as mad-cow disease, can be transmitted to humans, where it is known as variant Creutzfeldt-Jakob disease (vCJD). As in cows, this disease eats away at the nervous system, destroying the brain and essentially turning it into a spongelike structure filled with holes. Victims experience dementia; confusion; loss of speech, sight, and hearing; convulsions; coma; and finally death. Prion diseases are always fatal, and there is no treatment. Precautionary measures taken in Britain to prevent this disease in humans may have begun too late. Many of the victims contracted it over a decade earlier, when the BSE epidemic began, and the incubation period is long (vCJD has an incubation period of 10 to 40 years). A recent study concluded that 1 in 2,000 people in Great Britain carry the abnormally folded protein that causes vCJD. In spite of these numbers, the death rate from vCJD remains low. It is not clear whether this means that the incubation period for the disease is much longer than previously thought, or whether they may never develop the disease. What measures have been taken to stop BSE?arrow_forwardThere have been recurring cases of mad-cow disease in the United Kingdom since the mid-1990s. Mad-cow disease is caused by a prion, an infectious particle that consists only of protein. In 1986, the media began reporting that cows all over England were dying from a mysterious disease. Initially, there was little interest in determining whether humans could be affected. For 10 years, the British government maintained that this unusual disease could not be transmitted to humans. However, in March 1996, the government did an about-face and announced that bovine spongiform encephalopathy (BSE), commonly known as mad-cow disease, can be transmitted to humans, where it is known as variant Creutzfeldt-Jakob disease (vCJD). As in cows, this disease eats away at the nervous system, destroying the brain and essentially turning it into a spongelike structure filled with holes. Victims experience dementia; confusion; loss of speech, sight, and hearing; convulsions; coma; and finally death. Prion diseases are always fatal, and there is no treatment. Precautionary measures taken in Britain to prevent this disease in humans may have begun too late. Many of the victims contracted it over a decade earlier, when the BSE epidemic began, and the incubation period is long (vCJD has an incubation period of 10 to 40 years). A recent study concluded that 1 in 2,000 people in Great Britain carry the abnormally folded protein that causes vCJD. In spite of these numbers, the death rate from vCJD remains low. It is not clear whether this means that the incubation period for the disease is much longer than previously thought, or whether they may never develop the disease. If you were traveling in Europe, would you eat beef? Give sound reasons why or why not.arrow_forwardcan you explain why Bacillus anthracis can be pathogenic in a mouse and not be fought off by the immune system? I need help finding the answer in the article and explain in short answer link to article: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC106848/arrow_forward
- Penicillin was first used in the 1940s to treat gonorrhea infections produced by the bacterium Neisseria gonorrhoeae. In 1984, according to the CDC, fewer than 1% of gonorrhea infections were caused by penicillin-resistant N. gonorrhoeae. By 1990, more than 10% of cases were penicillin resistant and a few years later the level of resistance was 95%. Explain the various ways this resistance could be spread among the cells. Could this resistance pass to other infectious bacteria from N. gonorrhoeae?arrow_forwardThe human intestinal tract is home to a vast, diverse microbial community. The bacteria that comprise this microbial community serve a number of important, beneficial functions. However, some bacterial species have been suggested to play a role in certain forms of cancer. One such bacteria is Fusobacterium nucleatum (i.e., F. nucleatum). Investigators wishing to study the role of F. nucleatum in colorectal cancer developed a new assay for detecting these bacteria in tumor tissue. In controlled experiments, the test was highly sensitive in detecting F. nucleatum and also had high specificity. To examine consistency in their test findings, the investigators also conducted repeat tests in 50 tissue samples. From these repeat tests, the investigators observed that the overall number of samples in which F. nucleatum was detected was almost identical (10 out of 50 on the first test vs. 11 out of 50 on the repeat test); for 9 samples, F. nucleatum was detected on both the initial and the…arrow_forwardMost hospitals use hand sanitizers that claim to “kill 99.99% of illness causing germs”. What are some possible reasons that 0.01% of germs (germs = microorganisms and viruses) not affected by hand sanitizer? (In your answer, you should state what hand sanitizer is made of, and the mechanism by which it kills “germs”.arrow_forward
- (there are multiple right answers to this homework question but I can't tell which one is right) You are designing a phage therapy for a cystic fibrosis patient with an multi-antibiotic resistant Mycobacterium infection. The Mycobacterium infection is preventing the patient from taking immunosuppressant drugs that are needed for a successful lung transplant. The idea is that introducing the right phage to the patient will kill the Mycobacterium cells and allow the patient to go on immunosuppressant drugs that will ensure the new lung is not rejected by the body. In the first step of your phage therapy design process, you isolate the exact Mycobacterium strain from the patient. What is the most important thing must you establish next about this bacterial isolate? That the isolate is genomically stable so you can study it That the isolate is similar to Mycobacterium in other patients That the isolate rapidly evolves due to horizontal gene transfer That the Mycobacterium is…arrow_forwardWhich statement among A-D is false regarding bacterial toxins? A) O Hemolysıns are cell membrane disrupters that can rupture red blood cells. B) O Second mesengar pathway disrupters like cholera toxin produces a debilitating respiratory condition of the lungs. C) O Shiga toxin, tetanus toxin, and hemolysins are all types of exotoxins. D) O Superantigens elicit a hyperactive response by the immune system and can lead to shock. E) O None are false, A-D are all true statements.arrow_forwardHelp to explain this figurearrow_forward
- Which of the following highly contagious viruses is a single-stranded ribonucleic acid (RNA) virus with a helical capsid and envelope and is transmitted by coming in contact with respiratory secretions? "This is a highly contagious respiratory illness transmitted when an infected person coughs or sneezes virus particles into the air," the health department said in a written statement. "It's so contagious that if one person is sick and spreading measles, nine out of 10 people around them who aren't immune will get it, too." Group of answer choices a. Measles b. Parvovirus c. Coxsackie virus A d. Rhinovirusarrow_forwardA 65-year-old woman has a long-term central venous catheter for intravenous therapy. She develops fever and subsequently has multiple blood cultures positive for Staphylococcus epidermidis. All of the S. epidermidis isolates have the same colony morphology and antimicrobial susceptibility pattern, suggesting that they are the same strain. In what possible way do you think she has contracted the bacteria? Which link in the chain of infection has broken in this particular scenario and what will be your advice to avoid such infections?arrow_forwardA 65-year-old man who has been living for years with debilitating hepatitis C finally receives a liver transplant. Tragically, a week into his recovery he contracts Pseudomonas aeruginosa enterocolitis that develops into lethal sepsis. According to the model below, these events could reasonably be explained by which? Quorum sensing Cross-species effects Microbial products affecting the host Butyrate Indole Others Host products affecting the microbiota Hormones Intestinal epithelial cells Choose one: O A. overgrowth of otherwise commensal flora B. increased activity of methanogens O C. development of antibiotic resistance D. surgery-induced stress O E. change in normal diet to hospital foodarrow_forward
- Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage Learning