Micro Lab Exam 1 Review PDF

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Exam review for upcoming exam....

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Micro Lab Exam 1 Review Lab Unit 1- #1- Intro & Safety 1. Which biosafety level(s) include(s) known pathogens? (You may select more than one). - 1 - 2 - 3 - 4 2. -

Which biosafety level is the lowest and safest? (You may select more than one). 0 1 2 3 4

3. Which biosafety level should you assume is present in the lab at all times, including nonclass times? (You may select more than one). - 1 - 2 - 3 - 4 4. You have just spilled bacteria on your partner's lab book. What is the first thing you do? (choose one) - Ignore it - Wait in line to tell Dr. D - Warn your lab partner - Clean up the spill quietly 5. Your class before iMicro lab is Pilates, and you always bring your expensive BPA-free water bottle. It is fine as long as you don't drink out of it during lab. - True - False 6. You have a terrible cough, but know it's just allergies and so come to class anyway. You have brought some wonderful cough drops that contain menthol and honey, and its fine to use them during lab because they keep you from coughing on experiments. - True - False 7. You are finished with your MRVP inoculated test tubes with metal clamp lids. You should: (You may select more than one). - close them carefully and put them in the biohazard container - close them carefully and remove the tape and put them back in the incubator

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close them carefully and remove the tape and put them on the wire shelves for autoclaving empty the broth into the sink and put them on the wire shelves for autoclaving

8. You are finished with your Mannitol Salt Agar plates. You should: (You may select more than one). - tape them shut and put them on the wire racks for autoclaving - remove tape labels and put them in the broken glass box - parafilm them shut and put them in the garbage - put them in a ziploc, ask your table-mates if they have plates to throw away, and eventually throw the full ziploc into the red biohazard box. - put each of them in an individual ziploc bag and throw it into the red biohazard box. Lab Unit 1 -#2- Experimental Design 1. We are doing our urea hydrolysis test and we include one tube which we leave closed and do not inoculate. This is known as a(n): - uninoculated positive control - inoculated positive control - uninoculated negative control - inoculated negative control 2. For our ubiquity experiment, we will include a plate that remains closed and is never opened. This is a type of: - inoculated control - uninoculated negative control - inoculated positive control - experimental variable 3. -

In a good experimental design, we try to hold: (You may select more than one). controls steady all variables but the experimental variable constant all controls but the negative control constant all variables but the positive variable constant all variables constant

4. Correlation and causation are the same thing - True - False 5. Correlation means 2 things changing together - True - False Lab Unit 1 -#3- Media Prep 1. Which of these describe(s) an agar plate? (You may select more than one). - A colloid is poured into a plastic petri dish while warm

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A liquid is poured into a plastic petri dish and allowed to cool and harden A powder is dissolved into hot water and then sterilized A liquid is poured into a plastic petri dish and allowed to heat up

Lab Unit 1 -#4- Three Forces 1. Water is a polar molecule because - Santa likes it - it has a positive charge - it has a partial positive charge on one end and a partial negative charge on the other end - it has a negative charge 2. -

Sugar dissolves in water because it is: Uncharged Polar Nonpolar hydrophobic

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Which amino acids like to interact with nonpolar amino acids? Nonpolar Negative polar positive

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Which amino acids like to interact with water? (Select all of the correct answers) hydrophilic, polar all of them hydrophobic, non polar hydrophilic, charged

5. Amino acids are strung together like beads to form proteins. Therefore, the subunits of proteins are: - Lipids - Glucose - nucleic acids - legos - amino acids 6. "Complex carbohydrates" like cellulose (known as "fiber" in nutrition) are composed of simple carbohydrates, like glucose. Therefore, the subunit of cellulose is: - amino acids - nucleic acids - lipids - legos - glucose

7. Another name for "simple carbohydrates" is "monosaccharides" (which means "onesugar"). Another name for "complex carbohydrates" is "polysaccharides" (which means "many-sugars"). The subunit of polysaccharides is: - nucleic acids - amino acids - monosaccharides - polysaccharides 8. Glucose is a monosaccharide - True - False 9. Which of these are the three forces that control molecular interaction? (You may choose three) - Charge - Water - Magnetism - Hydrophobicity - shape 10. The "force" by which Charge affects molecules means: - the repulsion of negative charges for positive charges - the repulsion of positive charges for negative charges - the attraction of negative charges for one another - the attraction of positive charges for one another - the attraction of opposite charges for one another 11. Some molecules have charge because of: - Conductivity - Solubility - electron position - shape 12. Uncharged molecules are: (Choose two) - Soapy - water-fearing - water-loving - hydrophilic - hydrophobic 13. Hydrophilic molecules will: - dissolve in oil - not dissolve in anything - clump together in water - dissolve in water

14. Hydrophobic molecules will: - not dissolve in anything - clump together in water - dissolve in cells - dissolve in water 15. Charge and Hydrophobicity affect a molecule's shape - True - False 16. A molecule's shape affects its function (how it works) - True - False 17. An enzyme interacts with its substrate based on: (select more than one) - Charge - Alphabetically - all of the other answers - hydrophobicity - shape

Lab Unit 2 -#1- Broths, Streak, Spread, Pour 1. Why do you use a Bunsen burner in the Micro lab? - To heat chemicals - To sterilize tools - To speed up reactions 2. -

How long do you leave your loop or needle in the flame? 1 second until loop looks clean 3 seconds until metal glows orange 5 seconds until metal glows orange 1 second 10 seconds

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When inoculating a test tube, what do you do to sterilize the test tube opening? hold opening in flame until glass glows orange wipe with alcohol hold opening in flame 5 seconds flame bottom of tube for 5 seconds pass opening through flame once or twice

4. How do you hold the test tube when you inoculate it? - straight up and down so nothing spills

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you keep it in your test tube rack so you have two hands to work with at a 45 degree angle so microbes don't fall in sideways to make it easier to get loop in

5. What do you look for when you remove the loop from a seed broth, to know the bacteria is there? - chunks of bacteria on the loop - a film, kind of like the one in a bubble wand - nothing; you can't see bacteria 6. -

What do you do to the loop to cool it before touching a colony on a plate? touch the hot loop to a bacterial colony; the bacteria will cool it off wave it through the air to cool it off touch the hot loop to a sterile area on your agar plate wait patiently blow on it gently

7. . Do you need to be able to see globs of bacteria from a seed plate on the loop to transfer bacteria to another media? - Yes, about the size of a grain of rice - No, you don't have to see anything - Yes, about the size of a pencil eraser - No, about the size of a period in 24 point font is enough 8. -

What do you always do before setting your loop down? blow on it gently nothing wipe it on a paper towel sterilize it with flame wash it

9. . What is the point of doing a "streak for isolation" 4 quadrant streak plate? - The point of this is so that you get isolated colonies of each bacteria type. 10. What is the difference between a "streak plate" and a "streak for isolation plate?" - a streak for isolation plate uses four quadrants and a dilution technique; a streak plate just gets bacteria on the plate - there is no difference - a streak plate uses multiple quadrants and a dilution technique; a streak for isolation plate does not - a streak for isolation plate uses only one colony to start, while a streak plate uses multiple colonies

11. The advantage(s) to the spread plate are that: (You may choose more than one)

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you can dilute the original broth or sample, and get a countable number of colonies to determine the original bacterial concentration microaerophiles prefer shallow agar I chose the first two and got 0/1 anaerobes prefer shallow agar

Lab Unit 2 -#2- Sample Collection 1. Cotton is the most common material used in clinical swabs because it contains antibiotics - True - False 2. Sample-taking and storage is not that important for patient diagnosis - True - False 3. Once a sample is taken, it doesn't matter if it is stored so that bacteria can grow in the sample media - True - False 4. -

Once a sample is taken: (You may select more than one) it is important that it is refrigerated so that bacterial growth does not occur it is important that it is not stored in a nutritive broth that encourages bacterial growth it is important that it is not mixed with samples from other parts of the body it should be labeled with the patient's information and stored in the same vial as samples from other parts of the body

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Anaerobic bacteria: (You may select more than one) cannot be sampled accurately are sampled using a container with a chemical vial that binds to oxygen must be sampled with Calcium alginate swabs must be sampled with cotton swabs are sampled using a container with nutritive broth

Lab Unit 2 -#3- How to Think Like a Clinician - Look at puzzle on page 62 Lab Unit 3 -#1- Ubiquity 1. Ubiquity means: (You may select more than one) - existing everywhere constantly - omnipresence - a constant presence all around us, but not on us or in us except when causing disease 2. You will be taking environmental swabs around the lab for this experiment. Why? (choose two)

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to help understand what ubiquity means to help understand why our safety precautions are important to help understand how clean the lab is to help understand how incubators work to help understand how positive controls work

3. What is the importance of the closed and un-swabbed plates? (you may choose more than one correct answer) - It is a negative uninoculated control - It shows that the media is not contaminated - It is a negative inoculated control - It shows the bacteria is pure - It demonstrates the bacteria grew from a single sample 4. -

The temperature 37 degrees C is equivalent to: normal bacterial temperature normal room temperature normal human temperature refrigeration temperature

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The temperature 25 degrees C is equivalent to: normal bacterial temperature normal room temperature normal human temperature refrigeration temperature

Lab Unit 3- #2- Effects on Growth 1. To "denature" an enzyme means to: (You may select more than one.) - freeze it - crack it - melt it - alter its shape - alter its color temporarily - interfere with its function 2. Why is it important to thaw meat from the freezer carefully and for as short a time as possible? - It is only important if you aren't going to cook the meat - Bacterial enzymes are not destroyed by freezing, so bacteria survive and begin to replicate as the meat reaches room temperature. - Because the meat cells will break down and taste terrible - Because meat cells and bacteria cells have different thawing temperatures - Because bacteria could land on it in the kitchen and then begin to grow 3. Why is cooking meat to a temperature of 165 degrees F considered to destroy the replicating ability of all potential bacteria? - This is the temperature at which bacteria are directly killed by heat

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This is an unsafe temperature; to destroy bacteria replication the meat needs to reach 185 degrees F. This is the temperature at which meat cells are destroyed Bacterial enzymes are denatured at this temperature

4. Pure water has a pH of 7. Soil has a pH of 9. How many times more acidic is water than soil? It's not, it's more basic. - 1 - 2 - 5 - 10 - 20 - 100 - 200 - 1000 5. -

What is human body temperature in degrees Celcius? 26.7 21.0 25 37 40 98.6 100

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Most human pathogens are: Psychrophiles Mesophiles Thermophiles extreme thermophiles

7. Here is a graph of a bacteria's growth at different temperatures. Which is the optimum temperature for this bacteria's growth?

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5 degrees C 15 degrees C 25 degrees C 35 degrees C 45 degrees C 55 degrees C 65 degrees C . Describe what is happening to the bacteria at 220 minutes?

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cells are resting cells are dying cells are dividing expontentially cells are dividing and dying at the same rate

9. What is happening between 150 and 215 minutes?

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cells are dividing cells are dying cells are resting cells are dividing and dying at equal rates

10. What complication might you have trying to identify bacteria by Gram stain at 320 minutes? (There are still plenty of cells to stain, so the answer is NOT that there are too few cells). - stains only work on hundreds of cells - you can't see single bacterial cells in a microscope - bacteria are changing shape and cell wall characteristics as they die, which changes staining characteristics. - bacteria are replicating so quickly you cannot stain them

11. Match these labels to the parts of the data chart:

W- lag phase Y- stationary phase X- growth phase Z- decline phase 12. Listeria monocytogenes is a food-borne pathogen that can cause meningitis and miscarriage, especially in pregnant women and newborns. Listeria thrives in refrigerated foods. What would you classify it as? - Psychrophile - Mesophile - extreme thermophile - thermophile

13. . Given the example below, how would you classify it? (extreme thermophile, thermophile, etc?)

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Thermophile extreme thermophile mesophile psychrophile

14. Why was salt so valued in pre-refrigeration civilizations? (hint: I am asking WHY it was used as currency). - it was used as money - it was used as a preservative, to inhibit bacterial growth, based on bacterial osmotic limits - salt was tasty - salt changes the temperature of foods 15. Why are jelly and jam also called "preserves"? (Hint: look up how to make jelly or jam, like strawberry freezer jam) - They use high concentrations of sugar as a preservative, to limit bacterial growth due to osmotic pressure. - They use cans and cans automatically reduce bacterial growth - They use pectin as a preservative - Fruits naturally are bacteria free Lab Unit 3 -#3- Control of Pathogens 1. Hand soap (used on skin) is a: - Sterilizer - Disinfectant

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antiseptic

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Which is better to use multiple times a day? Soap Alcohol-based hand-sanitizer Triclosan-based hand-sanitizer nothing

Lab Unit 3 -#4- Colony Morphology

1. A. B. C. D. Lab Unit 4 -#1- Microscopy 1. Why is the wavelength of light the limiting factor of resolution? In other words, why do shorter wavelengths give you better resolution? - Shorter wavelengths give you better resolution because they are able to fit between and around very small objects being observed therefore getting a clearer image of their separation and shape. 2. -

Why do electron microscopes take images of higher resolution than light microscopes? electrons could be said to be smaller, or have a smaller wavelength electrons are clearer electrons are more powerful photons are messier photons are more powerful

3. You are using the medium power objective (10x) on a sample in our lab. What is the total magnification of the image? - 10x - 20x - 40x - 100x - 1000x 4. You are using the high power objective (40x) to examine a sample in our lab. What is the total magnification? - 10x - 20x - 40x - 100x - 400x 5. Immersion oil is able to increase resolution. How does it do that? - Immersion oil is able to increase resolution due to it having the same refractive index as glass and eliminates refraction as the light passes from the glass slide to the lens. Lab Unit 4- #2- Eukaryotes 1. What is a "trophozoite"? (Choose two). - a spore - a bacterium - an immature form of the parasite - a eukaryote - a prokaryote 2. -

What is an erythrocyte? a red blood cell an immature form of the parasite a type of diarrhea

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How is amoebic dysentery usually acquired? (Choose two) exposure by air eating contaminated food or water acquired in hospital settings (nosocomial) feces to mouth route sneezing or coughing

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Entamoeba histolytica is a: Bacteria Virus Eukaryote

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Giardia is often acquired from: (Choose two) brackish water clear flowing water pets contaminated fruit sneezing and coughing

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Giardia is a: Virus Bacteria Eukaryote Prokaryote

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Plasmodium is: (Choose two) a virus a bacteria a prokaryote a eukaryote the cause of river blindness the cause of malaria the cause of HIV

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Plasmodium is usually spread by: coughing and sneezing fecal to mouth route contaminated water mosquitoes ticks

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Algae are: (Choose two). Viruses Bacteria Prokaryotes Eukaryotes able to do photosynthesis

10. Which algae are clinically significant to humans in terms of disease, and why? (choose two) - red algae - green algae - oxygen production - parasite - toxin production

11. Yeast are a type of: (Choose two). - Virus - Bacteria - Prokaryote - Eukaryote - Fungi 12. Heterotrophs: - use photosynthesis - eat other living things - are always toxic - are always pathogenic - are always antibiotic resistant 13. Antibiotic treatment in females often results in a yeast infection because: - antibiotics kill the good bacteria, allowing the bad bacteria like yeast to overgrow - antibiotics are specific and kill only bad bacteria - antibiotics kill all the bacteria, and yeast can then infect the body - antibiotics kill normal flora bacteria as well as pathogenic bacteria, allowing Candida to overgrow Lab Unit 4 -#3- Bacteria Morphology 1. What shape and arrangement will Streptotoccus pyogenes have? (Select as many as needed) - Sphere - short rod - long rod - spiral - clusters - chains - four in a group I chose sphere, chains, four in a group. I made an 86% and scored 1.8/2.1 Lab Unit 4 -#4- Simple Stains 1. Safranin and Crystal Violet are basic stains because: (You may select more than one). - they are the simplest to use - they are the ones everyone starts with - they have a high pH - they have a positively charged chromogen - they will stick to the cell surface 2. -

The term "emulsion" refers to: the bacteria on the slide mixing the bacteria into liquid broth or water heating the slide

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The heat is used to: (You may select more than one). sterilize the clean slide stick the bacteria to the slide kill the bacteria "fix" the bacteria stain the bacteria

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Slides are often slightly hydrophobic, like most glass. This means that: water will break them water will scare them water will bead up on them none of the other answers

Lab Unit 4 -#5- Negative Stains 1. What color do the cells stain in a negative stain? - Clear - Purple - Pink - Black - Red Lab Unit 4 -#6- Capsule Stains 1. Why do we not use a heat-fixed emulsion on capsule stains? - It is important to not use a heat-fixed emulsion on capsule stains because it would melt the capsule and ruin the stain...