Question 1 Not yet graded / 3 pts Question 2 Not yet graded / 3 pts Question 3 Not yet graded / 10 pts BIOD 171 Q & A
(Latest 2023 / 2024) Essential Microbiology
Portage Learning Module 5 Exam
M5: Module 5 Exam - Requires Respondus
LockDown Browser + Webcam 2023 / 2024
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
List at least 3 observations a researcher would be sure to note while assessing an unknown microbial sample.
Your Answer:
size and shape, motility, chemical reactions, gram stain, color change
A lab researcher would be certain to note:
- Size and shape
- Any observable motility
- Gram status (positive or negative)
- The presence of any chemical reactions
- Changes in color localized to the organism or the surrounding media
- Capture (or draw) images of any of the characteristics described above
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? 1 / 2
Question 4 Not yet graded / 3 pts Question 5 Not yet graded / 10 pts Question 6
- / 2 pts
Your Answer:
The motility should be determined first. Observing motility requires a wet mount. Gram staining requires heat fixation. Heat fixing would kill the organism and motility would not be observable.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.
A facultative anaerobe is a microorganism capable of growth under what conditions?
Your Answer:
A facultative anaerobe is capable of growth under aerobic and anaerobic conditions.A facultative anaerobe is capable of growth under aerobic (with oxygen) and anaerobic (without oxygen) conditions.
As Streptococcus is catalase negative would it thrive or die in the presence of peroxides?Why?
Your Answer:
Streptococcus would die in the presence of peroxides because it is not able to break down the peroxides.Streptococcus would not survive in the presence of peroxides—it is unable to breakdown peroxides (catalase negative). Left unchecked, peroxides would damage the cellular integrity of Strep causing lysis/cell death.
Streptococcus is most often streaked onto:
Spirit Blue agar
- / 2