Module 5 Exam - Bio 171 Requires Respondus LockDown Browser...

Score for this quiz: 96 out of 100 Submitted Aug 11 at 11:24pm This attempt took 36 minutes. Question 1 3 / 3 pts The concept of treating all samples, whether known or unknown, as potentially hazardous (or pathogenic) materials is known as __________. Your Answer: universal precautions Universal precautions Question 2 3 / 3 pts List at least 3 observations a researcher would be sure to note while assessing an unknown microbial sample. Your Answer: 1. any motility 2.size/shape 3. gram status (gram-positive or gram-negative) 4. presense of any chemical reactions 5. changes in color A lab researcher would be certain to note: 1. Size and shape 2. Any observable motility 3. Gram status (positive or negative) 4. The presence of any chemical reactions 5. Changes in color localized to the organism or the surrounding media 6. Capture (or draw) images of any of the characteristics described above Question 3 10 / 10 pts While observing an unknown sample of limited amounts, a researcher must determine the following observations: (1) the presence of any motility and (2) its Gram status using the same sample—the liquid sample cannot be divided. Which would you determine first and why? Your Answer: You would need to determine the motility before gram status. You can observe motility on a wet mount and then heat fix your sample to gram stain your sample. If you were to begin with using gram staining, you would kill your sample with heat fixing, you would not be able to observe any motility. You must determine motility before determining the Gram status. Motility requires a wet mount, while Gram staining requires heat fixing the sample. If one were to begin with the Gram stain the heat fixation process would kill the organism, making any observations regarding motility impossible. The correct approach would be to place the liquid culture on a glass slide and determine its motility status. Next, the same liquid culture can be heat fixed and Gram stained.