🦠 Microbiology Solved MCQs with Answers

Practice 1927 approved 🦠 Microbiology questions with verified answers from the 🧬 Medical Science subject for Pakistan exams.

1927 solved MCQs

Which of the following is incorrect?Answer: Plant cells are less sensitive to shear than microbial cells The archaebacterium Halobacterium, an extreme halophile, and Sulfolobus, a thermoacidophile, can be cultured in the presence of antibiotics such as streptomycin and chloramphenicol becauseAnswer: they lack murein in their cell wall The isolation of the gonorrhoea - causing organisms, Neisseria gonorrhoeae,from a clinical specimen is facilitated by the use of media containingAnswer: certain antibiotics Anchorage -dependent cells requireAnswer: wettable surface for growth Stringent anaerobes can be grown in a media by taking special measure asAnswer: any of these Radical shifts in pH can be prevented by incorporatingAnswer: a buffer Which of the following bacteria can grow in acidic pH?Answer: Lactobacilli Cell size and cell number can be measured usingAnswer: coulter counter Which of the following is used for the proper maintenance and preservation of pure cultures?Answer: All of the above In the process of freeze drying, a dense cell suspension is placed in small vials and is frozen atAnswer: -60 to -78°C The solidifying agent commonly used in preparation of media is/areAnswer: both (a) and (b) Which of the following chemotherapeutic agents may affect the growth of Campylobacter jejuni?Answer: None of these To select cholera-causing bacterium, Vibrio cholerae, the pH of the medium is maintained at a pH ofAnswer: 8.5 For the selection of endospore-forming bacteria, a mixed culture can be heated atAnswer: 80°C for 10 minutes The concentration of agar to obtain semi solid media isAnswer: 0.5% or less Which of the following bacteria dies quickly after drying?Answer: Treponema pallidium Mac-Conkey medium is an example ofAnswer: differential medium Pseudomonas aeruginosa forms a blue water soluble pigment calledAnswer: pyocyanin Agar is used for solidifying culture media becauseAnswer: all of the above For the selection of lactobacilli present in cheddar cheese, the pH of the medium is maintained atAnswer: 5.35 A disease producing species occurring in a mixed culture can often be selected on the basis of itsAnswer: pathogenic properties Important example(s) of enriched medium/media is/ areAnswer: All of these Cell counting can be carried out byAnswer: all of the above Which of the following techniques may be performed quantitatively to determine the number of bacteria of a particular type?Answer: Both (a) and (b) Intestinal bacteria can grow in the presence of __________ whereas nonintestinal bacteria are usually inhibited.Answer: bile salts Which of the following problem makes it impossible to satisfy all of Koch's postulates?Answer: Microorganism cannot be isolated in pure culture A medium containing crystal violet dye plus sodium deoxycholate will allowAnswer: gram (-)ve intestinal bacteria to grow Which of the following bacteria can grow in alkaline pH?Answer: Vibrio cholerae All bacteria that inhabit the human body areAnswer: heterotrophs When a substance is added to a liquid medium which inhibits the growth of unwanted bacteria and favors the growth of wanted bacteria, it is known asAnswer: enrichment medium