Micro Exam 5 Portage Learning Revised Questions and Answers /2024

Define the concept of universal precautions. - Universal precautions is used when handling an unknown specimen. They should be treated as being potentially hazardous or pathogenic materials. So always use correct PPE List at least 3 observations a researcher would be sure to note while assessing an unknown microbial sample. - 1) the morphological characteristics (size/shape) 2) Presence of any motility 3) Gram status (+ or -) 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 samesample—the liquid sample cannot be divided. Which would you determine first and why? - Motility (1) because gram staining requires the sample to be fixed, which involves killing the organism. You then would not be able to observe the motility of the organism if you determine the gram status first. A facultative anaerobe is a microorganism capable of growth under what conditions? - A facultative anaerobe is capable of growth under both aerobic & anaerobic conditions. As Streptococcus is catalase negative would it thrive or die in the presence of peroxides? Why? - Die. Steptococcus is catalase negative and is unable to breakdown peroxides, therefore, it would die in the presence of peroxides. Streptococcus is most often streaked onto: Blood Agar EMB Agar Sprite Blue Agar Chocolate Agar - Blood agar The distinction for Lancefield subgroups lie in its (Select All that Apply) A)Catlyse Activity B)Carbohydrate composition of antigen C)Hemotlyic Acitivty D)All of the Above - B) Carbohydrate composition of antigen True or False. The Lancefield groups are used to subdivide antigenic groups of alpha-hemolytic Streptococcus. - False: The Lancefield groupings are used to subdivide beta-hemolytic strep Greater than 90% of all human streptococcal infections belong to: Group A Group B Group C Group D - Group A Rheumatic fever displays_____hemolytic activity and occurs when____is left untreated - Beta, Strep, Pharyngitis Left untreated, strep throat can progress to ______ , which displays _____ hemolytic activity. Strep, Septicemia, gamma Rheumatic fever; beta Strep, Pharyngitis; beta Strep Pharyngitis, alpha - Rheumatic fever; beta