Download Microscope Techniques and Microbiology Lab Procedures and more Exams Biology in PDF only on Docsity!
MICROBIOLOGY LAB FINAL EXAM
NEWEST 2024 QUESTIONS AND
DETAILED CORRECT ANSWERS
VERIFIED A+ STUDYGUIDE
If you find you're having trouble looking into the microscope with both eyes, what should you do? Question options: A) Close one eye, and just use the other eye to look into one of the oculars. You can see fine with one eye, so this shouldn't be a problem. B) Alternate looking with your right eye, and then your left eye to make sure one eye doesn't get more practice than the other. C) Grab the oculars and move them closer together, or further apart, until you can look into them comfortably. Correct Answer C) Grab the oculars and move them closer together, or further apart, until you can look into them comfortably. Where is the condenser located on the microscope, and how is it controlled? Question options: A) It's located between the objectives and the oculars, and it's controlled with the coarse and fine focus knobs. B) It's located directly under the stage, and it is controlled by a lever on the left side of the microscope. C)
It's located directly above the stage, and it is controlled by a knob on the right side of the microscope. Correct Answer B) It's located directly under the stage, and it is controlled by a lever on the left side of the microscope. How should the iris diaphragm slider be positioned in you want to look at a colorful specimen, like blue-green algae, or bacteria that have been stained with a dye? Question options: A) The iris slider should be positioned over to the left, so that the iris is wide open to improve resolution. B) The iris slider should be positioned over to the right, so that the iris is partially closed to increase contrast. C) The iris slider should be positioned over to the left when we're using the low power objective (like the 10x), but it should be moved to the right at high power (with the 40x or 100x.) Correct Answer A) The iris slider should be positioned over to the left, so that the iris is wide open to improve resolution. Which statement best describes the location of the coarse and fine focus knobs on our microscopes? Question options: A) The coarse focus knob is located on the right side of the microscope, while the fine focus knob is located on the left. B) The fine focus knob is located on the right side of the microscope, while the coarse focus knob is located on the left. C) There is both a coarse and fine focus knob on the left side of the microscope, while there is only a fine focus knob on the right.
100x objective into place, all without touching either of the focus knobs. C) Turn the coarse focus knob to lower the stage, making it easy to place a drop of oil directly onto the specimen. Correct Answer B) Turn the nosepiece on the microscope to move the objectives out of the way, add a drop of oil to the slide, and then rotate the 100x objective into place, all without touching either of the focus knobs. According to the lab standard operating procedures, you must wash your hands with soap and water for at least _________ before leaving the lab. A) 2 seconds B) 5 seconds C) 15 seconds D) 30 seconds E) 1 minute Correct Answer C) 15 seconds Which of the following statements does NOT correctly describe a rule that you must follow in the microbiology lab? A) There is no eating or drinking allowed in the microbiology lab. B) If you spill a bacterial culture on your lab coat, you must report it to your demonstrator. C) You must disinfect your workbench before and after each microbiology lab. D) No personal effects are allowed in the lab. You must find somewhere else to leave your winter jacket, textbooks, backpacks etc. while you attend the lab. E) None of the above. (All of the above statements correctly describe a rule that must be followed in the microbiology lab) Correct
Answer E) None of the above. (All of the above statements correctly describe a rule that must be followed in the microbiology lab) Which of the following statements correctly describe the lab coat policy in place in the microbiology lab? A) You must wear a buttoned lab coat at all times when working in the microbiology lab. B) Between labs your lab coat should be washed separately from other clothes with detergent and bleach. C) When you take your lab coat home to wash it you should carry it in a plastic bag to keep it separate from your other belongings. D) Your lab coat cannot be worn in any other lab until it has been washed. E) All of the above statements are true. Correct Answer E) All of the above statements are true. Which of the following statements best explains why you should never wear your microbiology lab coat in the hallways, either before or after a lab? (Even if it's clean.) A) Because your lab coat is likely to be contaminated with dangerous pathogens after a microbiology lab, and you may spread them out into the hallway B) Because you may pick up harmful microbes from the hallway and bring them into the lab on your lab coat C) Because the other people in the hallway don't know whether or not your lab coat is contaminated with dangerous microorganisms
Used Petri plates Swabs used to inoculate a Petri plate Used glass microscope slides
- In the large biohazard bin that sits beside the door
- Sharps/broken glass discard container
- In the regular waste paper baskets
- It doesn't matter where you discard this item, because if you put it in the wrong place, someone in charge will just move it to the right location anyway. Correct Answer 3 Paper towels used to disinfect the workbench 1 Disposable gloves 1 Used Petri plates 2 Swabs used to inoculate a Petri plate 2 Used glass microscope slides Choose all of the statements that are TRUE. (Note: this is a multiple select question. You must choose all of the true statements to get the question correct.) A) Paper towels used to disinfect the workbench must be disposed of in the biohazard bin B) Liquid cultures in glass test tubes should be poured down the sink with plenty of running water, and then the test tubes should be placed on the glassware trolley C) Gloves must always be disposed of in the biohazard bin (even if they weren't used to handle anything biohazardous) D)
Swabs, toothpicks, disposable plastic pipettes and anything else even remotely pointy should always be discarded in the sharps/broken glass container Correct Answer C) Gloves must always be disposed of in the biohazard bin (even if they weren't used to handle anything biohazardous) D) Swabs, toothpicks, disposable plastic pipettes and anything else even remotely pointy should always be discarded in the sharps/broken glass container What should you do if you accidentally spill a culture in the microbiology lab? (This is a multiple select question, choose all that apply.) A) Stop, and think about what the potential hazards are and how to deal with them in a logical order. B) Ask a TA for help cleaning the spill if there is broken glass involved. C) Move any leaking cultures to the glassware discard trolley immediately. D) Wash your hands if you spilled culture on them, or suspect that you might have spilled culture on them. E) Cover the spill with paper towel before soaking the paper towel with disinfectant. Correct Answer All are correct If a bacterial culture is splashed on your skin, what is the first thing you should do? Wash skin thoroughly with soap and water. Inform the lab instructor or TA. Continue working as the culture is risk group 1; therefore unlikely to cause disease.
Which of the following is a hazard for catching fire when working with the bunsen burners in MBIO 1010 lab? Gas line tubing Microscope power cord lab coat sleeves Hair (especially if long) All of the above Correct Answer All of the above Your bunsen burner is safest when A) it is pushed back, underneath the hutch that runs above our work benches B) the platform is locked in the down position, giving a blue flame C) it and the gas are turned off D) you have a lot of other equipment on your workbench, like test tube racks and microscopes Correct Answer C) it and the gas are turned off By law, all workplaces must have access to safety data sheets (SDS) for all controlled products used. Where can you find the SDS in the microbiology lab? Posted to the bulletin boards near the doors of the room In a dusty black binder at the end of each work bench Through links available on the installed laboratory computers You can't find them! The microbiology lab is a classroom, and therefore not considered a workplace under WHMIS legislation Correct Answer Through links available on the installed laboratory computers
True or False: Safety data sheets (SDS, but formerly called MSDS) are only for chemicals. There are no SDS for microorganisms. Correct Answer False Where will you find your microscope in the microbiology lab room? Question options: A) In the cupboard to the left of my work seat B) It will already be sitting on the counter top when I arrive. C) In the cupboard to the right of my work seat. D) On the supply bench at the side of the room Correct Answer C) In the cupboard to the right of my work seat. When disinfecting the workbench, you should: Question options: A) Skip the disinfectant and use a spray bottle of alcohol to evenly coat the entire surface of the work bench. B) Spread a thin layer of disinfectant on the counter and then let it dry down into a film on the surface of the work bench. C) Absolutely soak the counter with disinfectant, let it sit for a minute, and then sop up as much as you can with paper towels. D) Spread a thin film of disinfectant on the counter, and then after a minute, rinse it away with plenty of distilled water. Correct Answer B) Spread a thin layer of disinfectant on the counter and then let it dry down into a film on the surface of the work bench.
Be very careful! It's extremely delicate, and even gentle pressure can damage the objective. Give it one quick touch with the Kim wipe, and then put it away. C) Find a strong detergent, like the soap at the handwashing sinks. Use that to soak the Kim wipe and wipe vigorously. That's the only way to make sure you've removed all the oil. Correct Answer A) Push the spring loaded objective in, and give the objective a good wipe with a Kim wipe to remove all the oil. If you need to mix a culture of bacteria in a test tube, what is the best way to do that? Question options: A) Hold the test tube in a closed fist, and shake your hand up and down until the culture is well mixed. B) Hold the test tube by the glass, and use a finger on your other hand to tap the tube at the bottom. C) Hold the test tube by the cap, and swirl the tube vigorously to mix. Correct Answer B) Hold the test tube by the glass, and use a finger on your other hand to tap the tube at the bottom. In this lab period, you will make a wet mount of baker's yeast to look at it with your microscope. And the baker's yeast will be in a test tube (with a loose fitting metal cap). How will this test tube be labeled? Question options: A) The test tube should be labeled "Baker's yeast" because that's the easiest thing to remember! B)
The test tube should be labeled with the organism's proper latin species name Saccharomyces cerevisiae, because that's what it is! C) The test tube should be labeled with a short abbreviation, S. ce, because that saves the instructor time and space writing on test tubes! Correct Answer C) The test tube should be labeled with a short abbreviation, S. ce, because that saves the instructor time and space writing on test tubes! When making a wet mount for microscopy, you should: Question options: A) Draw a small circle on your microscope slide with a grease pencil or permanent marker, then place a single drop of culture in the middle of the circle, and then carefully place a cover slip on top. B) Place a drop of culture on the slide and then draw a small circle around the liquid with a grease pencil or permanent marker, and then carefully place a cover slip on top. C) Place a drop of liquid culture on the slide, and then carefully place a cover slip on top, afterwards draw a small circle on top of the cover slip with your grease pencil or permanent marker. Correct Answer Draw a small circle on your microscope slide with a grease pencil or permanent marker, then place a single drop of culture in the middle of the circle, and then carefully place a cover slip on top. Which of the following statements best explains why we always label our plates on the back (or bottom) instead of on the lid? Question options: A)
Used swabs are sharps so they should be placed tip first into the sharps container. C) Used swabs can be placed in the regular waste paper baskets as long as you put them back in the paper packaging before disposal. Correct Answer Used swabs are sharps so they should be placed tip first into the sharps container. What temperature do we incubate our plates at, when we have lab period once per week? Question options: A) We incubate them at 25°C so the colonies grow slowly. B) We incubate them at 37°C so the colonies grow quickly. C) We put them in the refrigerator so that colonies don't grow at all. D) We put them in an oven, so that all the microbes get cooked and die. Correct Answer We incubate them at 25°C so the colonies grow slowly. Practicing proper aseptic technique is essential to avoiding contamination and keeping our cultures pure. Which of the following activities will help you to avoid contamination? (Note: this is multiple select question, you must choose all of the Correct Answers to get the question correct.) Question options: A) Disinfecting your workspace before you begin the lab. B) Keeping the lids on our test tubes and Petri plates any time we're not actively working with those tubes or plates. C)
Flaming the mouth of the test tube after removing the cap, and again before putting the cap back on. D) Holding the test tube caps up off the counter while you're working. Correct Answer All! Which flame should you use when sterilizing your loop? Question options: A) The small orange pilot flame that you get when the Bunsen burner platform is in the up position. B) The larger blue flame that you get when the Bunsen burner is locked in the down position. Correct Answer The larger blue flame that you get when the Bunsen burner is locked in the down position. If you need to mix a culture of bacteria in a test tube, what is the best way to do that? Question options: A) Hold the test tube by the cap, and swirl the tube vigorously to mix. B) Hold the test tube in a closed fist, and shake your hand up and down until the culture is well mixed. C) Hold the test tube by the glass, and use a finger on your other hand to tap the tube at the bottom. Correct Answer Hold the test tube by the glass, and use a finger on your other hand to tap the tube at the bottom. How should you sterilize your loop in the microbiology lab? Question options: A)
sterilize your loop one last time, before putting it down on the counter. Where should you place the lid of the Petri plate when you are streaking a plate? Question options: A) I should place the lid on the counter facing down, so that nothing falls into the lid while I'm working. B) I should place the lid on the counter facing up, so that it doesn't pick up any microbes the counter surface. C) I should not place the lid anywhere. I should hold it right above the plate while I'm streaking and replace it as soon as I can. Correct Answer I should not place the lid anywhere. I should hold it right above the plate while I'm streaking and replace it as soon as I can. 1 mL =? uL 0.1mL =? uL Correct Answer 1000 uL (on pipet 1- 0 - 0) 100 uL (on pipet 0- 1 - 0) What is the fastest way to break the P1000 mechanical pipette? Question options: A) Push the tip ejector button to many times (when you're discarding the used tips.) B) Turn the dial up past the maximum setting of 1ml (or 1000 μl.) C) Turn the dial down below the minimum setting of 0.1 ml (or 100 μl.) D)
Push the pipette down into the tip too hard (when you're obtaining a new tip.) Correct Answer Turn the dial up past the maximum setting of 1ml (or 1000 μl.) What does it mean when the box of tips for the mechanical pipettes has a piece of autoclave tape covering the opening? Question options: A) It means that the box of tips has been sterilized in the autoclave, but someone has already opened the box. B) It means that the box of tips has not yet been sterilized in the autoclave. C) It means that the box of tips has been sterilized in the autoclave, and has not yet been opened. Correct Answer It means that the box of tips has been sterilized in the autoclave, and has not yet been opened. What should you do if you are the first person to open a new box of tips for the mechanical pipette? Question options: A) You should remove the piece of autoclave tape from the box entirely and throw it in the garbage. This tells other people that the tips absolutely not sterile anymore. B) You should remove the piece of tape briefly to take a tip, and then return it to the front of the box as soon as you have one, so that the box doesn't look like its been disturbed. C) You should move the piece of autoclave tape from the front of the box to the top, to tell other people that the box has been opened. Correct Answer You should move the piece of autoclave tape
