1.
A phagover is _____________________
Correct Answer
B. Strains having the same pHage sensitivity
Explanation
A phagover refers to strains of bacteria that have the same sensitivity to a specific phage. This means that these strains can be infected by the same phage and are affected in a similar way. It is a term used to describe a group of bacterial strains that share a common susceptibility to a particular phage.
2.
Which of the following have characteristic intracellular inclusion bodies?
Correct Answer
B. Chlamydia
Explanation
Chlamydia is the correct answer because it is known to form characteristic intracellular inclusion bodies. These inclusion bodies, called chlamydial inclusions, are formed within the host cell cytoplasm during the intracellular replication of Chlamydia bacteria. These inclusions are composed of both host and bacterial proteins and can be visualized using staining techniques. In contrast, Candida, Rickettsia, and Mycoplasma do not typically form intracellular inclusion bodies.
3.
Which of the following cannot be used to identify a virus?
Correct Answer
B. Gram stain
Explanation
Gram stain is a method used to identify and classify bacteria based on their cell wall composition. It involves staining the bacteria with crystal violet dye, followed by iodine, alcohol, and safranin. The bacteria are then observed under a microscope. Since viruses do not have a cell wall, they cannot be identified using the Gram stain method. Therefore, gram stain cannot be used to identify a virus.
4.
The gram stain and acid fast stain are based on chemical properties of the _____________
Correct Answer
A. Cell walls
Explanation
The gram stain and acid fast stain are both used to identify and classify bacteria based on their cell wall composition. The gram stain differentiates bacteria into two groups: gram-positive (purple) and gram-negative (pink) based on the differences in their cell wall structure. The acid fast stain is used to identify bacteria with a waxy cell wall, such as Mycobacterium tuberculosis, which causes tuberculosis. Therefore, the correct answer is cell walls.
5.
Which is the most common specimen collected in suspected cases of lower respiratory infections?
Correct Answer
B. Sputum
Explanation
The most common specimen collected in suspected cases of lower respiratory infections is sputum. Saliva and breath are not commonly collected as specimens for diagnosing lower respiratory infections.
6.
Which is the least satisfactory for anaerobic specimen collection or transport?
Correct Answer
A. Swabs
Explanation
Swabs are the least satisfactory for anaerobic specimen collection or transport because they can introduce oxygen into the specimen, which can affect the growth and viability of anaerobic bacteria. Anaerobic bacteria require an oxygen-free environment to survive and grow properly. Swabs have a larger surface area and can absorb oxygen from the air, making them less suitable for collecting and transporting anaerobic specimens. Tissues, aspirates, and capped syringes provide a more suitable environment for anaerobic specimen collection and transport.
7.
The most common method used for the collection of urine is
Correct Answer
A. The clean catch method
Explanation
The clean catch method is the most common method used for the collection of urine. This method involves cleaning the genital area before collecting the urine sample to avoid contamination. It is a non-invasive method that allows for a midstream urine sample to be collected, which helps to minimize the risk of contamination from the external genitalia. This method is widely used in clinics and hospitals for routine urine testing and diagnosis of urinary tract infections.
8.
Which of the following represents a molecular method of testing?
Correct Answer
A. Plasmid fingerprinting
Explanation
Plasmid fingerprinting is a molecular method of testing because it involves the analysis of plasmids, which are small, circular DNA molecules found in bacteria. This technique allows scientists to compare and identify different plasmids based on their unique patterns or "fingerprints". In contrast, microscopy is a technique that involves the use of a microscope to visualize and study the structure and characteristics of cells or microorganisms. Selective media and differential media are types of culture media used to selectively grow and differentiate specific types of microorganisms, but they do not involve molecular analysis like plasmid fingerprinting.