Microbes in Human Welfare Questions and Answers

You add an appropriate amount of an antibiotic to a turbid broth culture of bacteria, and within a few minutes the culture visibly clears. a) Can you tell the mechanism of action from these results? b) If so, what is it? c) If not, what tool would you need to figure it out?

Determine whether the given statements describing prokaryotic organisms is true or false. Prokaryotic organisms occupy environments where other organisms could not survive. Prokaryotic organisms are important producers of organic carbon compounds. Over 75% of bacteria are known human pathogens. Prokaryotic cells release carbon dioxide contributing to global climate change

The sludge removed from earlier steps in wastewater treatment can further be broken down into stable solids and methane (natural gas) by: a) aerobic digestion b) disinfection c) anaerobic digestion d) sedimentation

You grow a pure culture of Mycoplasma pneumoniae and notice that the cells vary in shape, with some being rods, others cocci, and others are coccobacilli. This phenomenon is best termed: a) pleomorphism b) mutation c) biofilm formation d) polymorphism

The purpose of heat-fixing a bacterial smear is: a) to make the sample stick to the slide b) to inactivate the enzymes of the bacteria, so they don't lead to degradation of the smear d) to help the sample take up the dye d) all of the above

If this experiment was repeated and the entire set up was placed in a dark closet, predict what would happen to each of the organisms in the jar. Use your knowledge of photosynthesis and respiration to justify your answer.

The growth temperature is a small range of temperatures in which the microbe experiences the fastest rate of metabolism and growth. two of these are correct optimum minimum maximum

11. The salinity of a small inland lake has recently started to increase. Researchers are planning to study the lake over several decades to investigate how freshwater organisms survive significant changes in their natural habitat. Which of the following physiological mechanisms will the researchers most likely observe among the surviving organisms in the lake? a. Prokaryotic organisms will use various mechanisms to counteract swelling of cells as a result of increased water uptake. b. Single-celled organisms will use various mechanisms to counteract the increased flow of water from cells to the environment. c. Eukaryotic organisms will use various mechanisms to counteract the diffusion of positively charged ions across the cell membrane. d. Multicellular organisms will use various mechanisms to counteract the loss of cell adhesion as a result of calcium deficiencies.

Gonorrhea can be treated with antibiotics such as amoxicillin ampicillin azithromycin all the choices

If a fly landed on animal feces, picked up Salmonella on its feet, and then transferred the bacteria to food by walking on it, the fly would best be termed a: A) fomite B) mechanical vector C) biological vector D) zoonosis E) pathogen

Which of the following best describes the patterns associated with the microbial death phase of the growth curve? a. None of the above, we don't talk about cell death b. the cells in the population die at a constant rate c. the cells in a culture die at varying rates, alternating between fast and slow death rates. d. all the cells in a culture die at once

Consumption of a buffet food item contaminated with Staphylococcus aureus at a wedding reception results in many people becoming ill. This would best be described as a: A) pandemic B) zoonosis C) vertical transmission D) point source epidemic E) propagated transmission epidemic

Order the following steps a microorganism takes in the process of establishing disease. 1 2 3 4 Microbe overcomes host defenses. Microbe attaches to receptor on host. Microbe enters through its portal of entry. Disease is established.

Endotoxins are... a. the most lethal substances known b. encoded by bacterial plasmids or phages c. proteins usually with two parts: A and B d. generally degraded by autoclaving (121C for 20 minutes) e. none of the above

Biology why is it important to reduce the amount of biodegradable organic matter and nutrients during sewage treament?

Discuss the factors which contribute to limitation of sago starch usage in food products. Suggest modification steps that need to be taken to further enhance its potential as functional ingredient in food industry.

For enzymes, shape matches function. Once a substrate is matched to an enzyme in "lock and key" fashion it is a(n) A. active molecule. B. polypeptide bond. C. substrate enzyme complex. D. functional protein.

In higher order protista and eukaryota, the nuclear membrane dissolves completely, and the process is called [? ]. meiosis mitosis binary fission

Condensed, packaged DNA is called a chromosome and loose DNA is/are [?] that is/ are open and readable. .. chromatin chromatids histones

Cell division in [?] is more complicated than prokaryotes due to the presence of a encasing the DNA. eukaryotes fungi archaea

You just transferred your bacteria into another tube. You want the bacteria in this tube to multiply quickly so you'll have enough bacteria for your next experiment in 1-2 days. Where in the lab (or what "device") would you put the new tube of bacteria and why?

Which method you wouldn't use to differentiate Proteus vulgaris from Salmonella sp.? A. Urea test B. Inoculation to BAP C. EnteroPluri test tube D. Inoculation to McConkey agar E. All tests can be used

The Mountain Pine Beetle vs an Ecosystem The lodgepole pine grows in the North American west, as far north as the Yukon. It tolerates most soil conditions; cold, wet winters; and warm, dry summers. Seed cones can withstand freezing temperatures and most insects. The trees have fairly thin bark and a shallow root system, making them susceptible to damage by fire and insects; however, the high temperatures of fires release the seeds to quickly regenerate trees after a forest fire. During the last hundred years, forest fires have been controlled and suppressed. The mountain pine beetle is a common parasite of the lodgepole pine. Adult beetles bore through the thin bark to lay eggs and deposit a fungus carried on their bodies. The larvae live in and feed on the bark during the winter, as does the fungus. The bark damage usually kills the host tree, although sustained temperatures of -25 °C during the early fall or late spring or temperatures of -40 °C during winter can kill the larvae. Infestations usually last 5 to 7 years and happen in 20- to 40-year cycles. The pine beetle infestation began in British Columbia in 1993, and over a decade later residents in affected areas are reporting: • small mammals such as squirrels have disappeared song birds have left the area trap lines are increasingly empty • cougars are coming to settled areas and preying on family pets • devil's club, a plant used for Aboriginal medicine, is increasingly hard to find Analysis 1. What biotic and abiotic components of the environment affect the life cycle of the lodgepole pine? What biotic and abiotic components of the environment affect the life cycle of the mountain pine beetle? 2. Can you suggest reasons why the current mountain pine beetle infestation has lasted longer than the usual 5 to 7 years? 3. What can you infer from the local reports about the impact of the loss of the trees on other organisms? Extension 4. Choose one of the following roles and write or present a short paragraph on how the pine beetle infestation affects you as: a) a local elder b) a logger c) a planner for the department of forests d) a wilderness tour operator

In a carbohydrate fermentation test, how do you know if the bacteria fermented the carbohydrate in the medium? The pH increases when bacteria ferment the carbohydrate and the pH indicator turns red The medium turns yellow AND gas is collected in the tube The medium turns yellow with or without gas production Bacteria grow on the surface of the medium where there is more oxygen for fermentation

resuspended the bacteria in 0.5ml of Solution 1 and then added lysozyme to a concentration of 50µg/ml. If we had a lysozyme stock concentration of 10mg/ml, calculate the stock volume that needed to be added. (HINT: Use C1V1 = C2V2)

After growing an enteric organism overnight in SIM media, Jeniffer added a few drops of Kovacs reagent. The top portion of the culture media turned red. Which of the following species is this likely to be?" E. coli Klebsiella Enterobacter all of these

How would you culture capnophiles bacteria in the lab? In TSA medium (the one that we frequently use in the lab) exposed to air In a sealed jar where oxygen is chemically removed In an anaerobic chamber In a candle jar In an enriched medium such as blood agar

During this bacterial growth phase, death rate is much higher than growth rate because there is very limited or no food. death phase Lag phase Log phase Stationary phase Foodless phase

What group of microorganisms do not usually call the skin home? Spirochetes Micrococci Staphylococci Corynebacterium

The purpose of studying an urban microbiome is to study the diversity of microbiome and observe the change of the microbiome in the urban area over years. True False

Choose the most accurate answer about Bile esculin medium? a) It's a differential medium for bacteria that hydrolyze esculin and a selective medium for Gram negative b) It inhibits the growth of Gram-negative bacteria c) It's a differential medium for all esculin hydrolyzing bacteria d) It's used to identify Gram positive bacteria that hydrolyze esculin

How would you classify the distribution and appearance of the growth in broth of this bacterium? Flocculent Uniform fine turbidity Sediment Pellicle

The proportion of microorganisms killed after a sterilization treatment can be estimated from which one of the following standards. Lethality factor (F) Z value Critical value Inactivation factor (IF) Sterility assurance level (SAL)

Why do Gram-negative bacteria tend to be less sensitive to antibacterial drugs in general? a. Many antibacterial compounds can pass through the thin peptidoglycan layer of a Gram-positive bacterial cell. b. Many antibacterial compounds cannot pass through the outer membrane of a Gram-positive bacterial cell. c. Many antibacterial compounds cannot pass through the thick peptidoglycan layer of a Gram-negative bacterial cell. O d. Many antibacterial compounds cannot pass through the outer membrane of a Gram-negative bacterial cell.

Which term best describes a drug that kills microbes? a. microbiocidal b. microbiostatic c. narrow-spectrum d. broad-spectrum e. antibiotic

What is the purpose of including phenol red in triple sugar iron (TSI) medium? a. Phenol red ferments the sugars. b. Phenol red can be reduced to hydrogen sulfide. c. Phenol red is a pH indicator. d. Phenol red inhibits catalase. e. Phenol red undergoes fermentation.

What are the four basic steps involved in this bacterial identification lab?

After completing sample A, perform DNA sequence analysis on any two of the other five samples (B, C, D, E or F). Write in the letter of the sample you choose and the scientific name of the bacterium (after doing a BLAST search).

rCptA was produced in E. coli True False

Why facultative anaerobes prefer to grow in the presence of oxygen than without oxygen? Because the highest number of ATPS per glucose is produced by aerobic respiration Because oxygen is their preferred nutrient Because they are only able to do aerobic respiration Because they can only live for a short time in the absence of oxygen All of the above

5. When bacterial cultures are grown in the lab, products of bacterial metabolism can build up making the environment too acidic or alkaline for the bacteria to thrive. What is the best thing to add to the growing medium to keep the bacteria healthy? a. ever clear b. a base c. buffer d. protein

Bacteria that are no longer killed effectively by antibiotics (medicine that fights infections) are called "antibiotic resistant." Which of the following is NOT true about bacteria that are antibiotic resistant? a. These bacteria are naturally resistant to certain antibiotics. b. These bacteria can spread resistance through reproduction. c. These bacteria can transfer resistance genes to other bacteria through DNA transfer. d. These bacteria cannot transfer resistance genes to other bacteria through DNA transfer.

Different people's cell phones are home to different types of microbes. Why might this be? a. The types of microbes living on cell phones changes randomly. b. The cell phone owners did not wash their hands after using the bathroom. c. The types of microbes living on cell phones reflect the same types of microbes living on the skin of their owners. d. Different cell phones have different abiotic (non-living) factors. These factors select for different types of microbes that are able to survive on different types of cell phones.

Why are parasite considered a microorganism? They are small. They produce tissue and organs They have microscopic larval stages They are infectious agents Eukaryotes can be microbes, not just prokaryotes.

Some bacteria are metabolically active in hot springs because they are able to maintain a lower internal temperature. their enzymes have high optimal temperatures. high temperatures make catalysis unnecessary. their enzymes are completely insensitive to temperature.

What makes NIOSH unique among federal research institutions? a)It works with the Department of Labor and other government agencies to promote occupational safety and health. b)It is a part of the Centers for Disease Control (CDC) and it's also responsible for development of the technical portions of OSHA standards. (c)It is the only government agency that only specializes in research on toxicity levels and human tolerance levels of hazardous substances. d)It has the authority to conduct research in the workplace, and to respond to requests for assistance from employers and employees.

Which of the following statements about E. coli is true? Some infections can be fatal to humans. It occurs naturally in food crops. Most people can ingest it without harm. It dies quickly outside of its host.

Why during commercial fermentation does special care need to be taken to keep the vats sealed during the process? To keep any bacteria from consuming the yeast If oxygen is allowed to be present the fermentation process will not happen Excessive amounts of carbon dioxide will be produced Only glycolysis will happen

What is a biofilm and how does it help microbes? Challenge Questions 1. In this lecture, there were 2 examples of coordinated bacterial activity. What were they? 2. How does the toxin/antitoxin system work to maintain a plasmid inside a cell

Date of Visit: 12/24/YYYY Patient Name: unknown Date of Birth: 1/31/1975 Gender:M Patient Type: Inpatient Reason for Visit:Psoriasis Notes/Comments: Unit 5 Case Study 3 PREPROCEDURE DIAGNOSIS: Acute respiratory failure due to Hanta Virus POSTPROCEDURE DIAGNOSIS: acute respiratory failure due to Hanta Virus INDICATIONS: The patient was placed on Dovonex at night and triamcinolone during the day last time without improvement in his psoriasis. The patient would like to start photochemotherapy with PUVA today. PROCEDURE: Patient was intubated and placed on a ventilator for 16 hours. Patient was transferred to the University Hospital for further treatment.