Question: In the reading “Taking antibiotics early in life leaves mice prone to obesity,” mice that received antibiotics and were then fed a high-fat diet gained significantly more weight than mice that did not receive the antibiotics but were fed the same high-fat diet. What did the scientists conclude was the cause of the weight gain?
Answer Options: The antibiotic treatment changed the gut microbiome of the mice. The antibiotic itself changed the metabolism of the mice. Correct Answer: The antibiotic treatment changed the gut microbiome of the mice.
Question: Sometimes scientists identify bacteria in an environment by determining the DNA sequence of a bacterial gene. What is a limitation of doing this?
Answer Options: There is no limitation – with this incredible technology, scientists can quickly learn everything there is to know about all the bacteria in an environment. Because they’re so small, we know too little about bacteria to be able to use this technique on most of them. The sequence of the gene will only tell a scientist what bacteria are there, but will not tell them what functions the bacteria have in the environment. This technique cannot be done on bacteria in the human microbiome because they have evolved to no longer have the gene. Correct Answer: The sequence of the gene will only tell a scientist what bacteria are there, but will not tell them what functions the bacteria have in the environment.
Question: “Within our bodies, there are about 1.3 times as many bacterial cells as there are human cells.” The preceding statement is…
Answer Options: True False Correct Answer: True
Question: “The number and diversity of bacteria in our microbiome varies from location to location on/in our bodies because each location has a slightly (or very) different microenvironment.” The preceding statement is…
Answer Options: True False Correct Answer: True
Question: “No two people have the same microbiome.” The preceding statement is…
Answer Options: True False Correct Answer: True
Question: Which of the following factors have been shown to influence the composition of our microbiome, as discussed in this course? Select ALL that apply.
Answer Options: Taking antibiotics Our genes/genetics If we are sick or healthy Our age What pets we have Method of birth: C-section or vaginal Correct Answer: Taking antibiotics Our genes/genetics If we are sick or healthy Our age What pets we have Method of birth: C-section or vaginal
Question: Which of the following is something that beneficial (‘good’) bacteria do to help control the population of pathogenic (disease-causing) bacteria in our bodies, as discussed in this course?
Answer Options: They produce antacids to change the pH of our mouth, preventing pathogenic bacteria from growing. They compete for the available nutrients, which means they can make it hard for pathogenic bacteria to find food to eat. They spawn viruses that target the pathogenic bacteria. They produce a large amount of acid to help us digest our food and this also breaks down the surface of the pathogenic bacteria. Correct Answer: They compete for the available nutrients, which means they can make it hard for pathogenic bacteria to find food to eat.
Question: Match the terms with the most relevant phrase.
Answer Options: Some indigestible plant fibers, for example. A beneficial microbe that we intentionally consume. A bacterium that helps to modulate inflammation in our intestines, by training our immune system. A microbe that can cause abdominal pain and diarrhea following antibiotic treatment. Correct Answer: Clostridium difficile: 4 Bacteroides fragilis: 3 Probiotic: 2 Prebiotic: 1
Question: Most bacteriocins have a narrow range of activity, in terms of which bacterial species they can inhibit. How would this trait be a benefit compared to conventional antibiotics? Choose the most applicable, correct answer.
Answer Options: They can be used to treat patients, because they are selectively toxic. They only kill bacteria, not viruses. They make effective probiotics and can be eaten to counteract the negative effects of antibiotics on our microbiomes. They could be used to selectively kill one type of ‘bad’ bacteria, without harming many of the ‘good’ bacteria in our microbiome. Correct Answer: They could be used to selectively kill one type of ‘bad’ bacteria, without harming many of the ‘good’ bacteria in our microbiome.
Question: “Transplants of feces from a healthy donor can help to repopulate a person’s intestines with beneficial bacteria, to help fight C. diff infections, and are typically used after other treatments have failed.” The preceding statement is…
Answer Options: True False Correct Answer: True
Question: Which of the following statements about the differences and similarities between viruses and bacteria is NOT true?
Answer Options: Bacteria can perform biochemical reactions that are considered to be ‘life processes’, while viruses do not. All bacteria use DNA for their genome, while some viruses use DNA and some viruses use RNA for their genome. Both bacteria and viruses need to get inside the cells of other organisms in order to reproduce. There are vaccines that are effective against viruses (i.e., at preventing viral diseases) and other vaccines that are effective against bacteria/bacterial diseases. Correct Answer: Both bacteria and viruses need to get inside the cells of other organisms in order to reproduce.
Question: What is the viral capsid made of?
Answer Options: Lipid DNA or RNA Protein Nucleic acid Correct Answer: Protein
Question: Where do some viruses get their envelope?
Answer Options: From the host cell’s membrane The host cell synthesizes it from a viral gene The virus synthesizes it from a viral gene From the stationery store Correct Answer: From the host cell’s membrane
Question: In general, how does the size of a virus compare to that of a bacterium?
Answer Options: Viruses are generally bigger than bacteria. Viruses are generally the same size as bacteria. Viruses are generally smaller than bacteria. Correct Answer: Viruses are generally smaller than bacteria.
Question: Which of the following lists the life cycle of a virus in the correct order, where the first step upon encountering a host cell is step 1.
Answer Options: Attachment, Replication and Biosynthesis, Assembly, Release Release, Assembly, Attachment, Replication and Biosynthesis Replication and biosynthesis, Assembly, Release, Attachment Assembly, Release, Attachment, Replication and Biosynthesis Correct Answer: Attachment, Replication and Biosynthesis, Assembly, Release
Question: “All bacteria and viruses cause disease and are thus not beneficial to humans.” The preceding statement is…
Answer Options: True False Correct Answer: False
Question: “Antibiotics can be used to treat viral diseases.” The preceding statement is…
Answer Options: True False Correct Answer: False
Question: Which branch of our immune system is involved in giving us long-lasting immunity to diseases after infection or vaccination?
Answer Options: Adaptive immunity Innate immunity Prosecution immunity All of the above Correct Answer: Adaptive immunity
Question: Before smallpox was eradicated, people used different methods to try to prevent smallpox infection. Which of the following is one of the methods discussed in this course?
Answer Options: Edward Jenner, a doctor, injected people with smallpox virus that he had inactivated by treatment with lye (a strong chemical). People drank tonic water because the quinine in tonic water protects against viral infections. Variolation was a practice that involved scratching people with smallpox pus and was introduced to the Boston area of North America by an African slave named Onesimus. People had ‘smallpox parties’ to try to get infected, thus providing subsequent immunity. Correct Answer: Variolation was a practice that involved scratching people with smallpox pus and was introduced to the Boston area of North America by an African slave named Onesimus.