MMSC 438 EXAM 2 SET Q&A

MMSC 438 EXAM 2 SET Q&A Most common STD - ANSWER Chlamydia (1.7 mil cases) Skin normal biota is coagulase-negative staph, cornybacterium, and microbacterium smegmatis - ANSWER males (all ages) Skin normal biota staph and corynbacterium - ANSWER females (prepuberty and post-menopause) Normal biota of the skin for reproductive-age females in some cases- they carry it asymptomatically - ANSWER GBS Normal biota of the skin for ___________ includes Enterobacteriaceae and anerobes, strep and staph, and LACTOBACILLI (predominant organism) - ANSWER reproductive-age females A disadvantage of the first DNA probes and nucleic acid amplification tests were that - ANSWER only one agent could be detected at a time Later, multiplex PCR assays were developed. This permited the identification of - ANSWER several pathogens in one test (ex: FilmArrayTM (BioFire) gastrointestinal panel can detect 22 targets, that includes bacteria, parasites, and viruses, in about an hour. These types of assays are starting to replace standard cultures.) The most recent advancement in clinical microbiology is the use of _________________This technique has gained popularity for its accuracy, speed and the ability to batch specimens (run several specimens simultaneously) - ANSWER MALDI-TOF MS (matrix-assisted laser desorption/ionization-time of flight mass spectrometry) Real-time polymerase chain reaction (results obtained in real time) - ANSWER Q-PCR the reverse transcription-polymerase chain reaction that utilizes RNA target - ANSWER RT-PCR Amplification of target nucleic acid increased number of copies of target DNA or RNA - ANSWER PCR (polymerase chain reaction) In PCR, DNA copies (__________) = determine presence or absence of Specific gene, specific sequence (1 to 100 bp differences) - ANSWER amplicon Template DNA Four DNA bases, deoxynucleotide triphosphates (dNTPs): dATP, dCTP, dTTP, dGTP DNA polymerase,Taq polymerase Reaction buffers 2 oligonucleotide primers- 20 to 30-mers (20 to 30 oligonucleotides long) Intact DNA templateContains DNA sequence of interest to be amplified - ANSWER Components of PCR How many cycles are usually in PCR Thermal Cycling? - ANSWER 35 3 different temperature steps/single cycle for PCR Thermal Cycling 1. Denaturation of template (94-95C) 2. Annealing (50-70C)Primer binding to template = dsDNA formation 3. ____________________ - ANSWER Primer extension (72C)