Introduction To Microbiology Quiz Questions And Answers

Explanation
The methods used to identify bacteria include microscopic appearance, colonial morphology, selective or indicating media, gram and other stains, biochemical reactions, gene probes, and antibody reactions. These methods allow scientists to observe the physical characteristics of the bacteria, such as their size and shape under a microscope, as well as their appearance on agar plates. Selective or indicating media helps to isolate specific types of bacteria, while gram and other stains provide information about the cell wall composition. Biochemical reactions can be used to determine the metabolic capabilities of the bacteria. Gene probes and antibody reactions involve the use of specific genetic markers or antibodies to identify the presence of certain bacteria.

Explanation
An O&P stool test is a laboratory test that is used to detect the presence of parasites in the digestive tract. The test can identify various forms of parasites, including protozoan cysts and trophozoites, helminthes ova (eggs), and larvae or immature forms of helminthes. These findings can help diagnose parasitic infections in individuals and guide appropriate treatment. The presence of a chicken egg and arthropod mother in the test would not be expected findings and may suggest contamination or other issues with the test.

Explanation
The correct answer includes Salmonella, Shigella, Escherichia coli O157:H7, Clostridium difficile, Campylobacter, and Plasmodium. These organisms are commonly detected in stool specimens and are known to cause various gastrointestinal infections. Salmonella and Shigella are bacteria that can cause severe diarrhea and abdominal pain. Escherichia coli O157:H7 is a strain of E. coli that produces toxins and can cause bloody diarrhea. Clostridium difficile is a bacteria that can cause antibiotic-associated diarrhea. Campylobacter is a common cause of bacterial gastroenteritis. Plasmodium is a parasite that causes malaria. HCG is not a pathogenic organism and is not usually detected in stool specimens.

Explanation
The statement is true because the B-D vacutainer urine C&S transport kit contains a freeze-dried preservative that helps preserve the urine and prevent the overgrowth of bacteria during transport. This allows for accurate testing of the urine sample without the risk of bacterial contamination.

Explanation
The statement is true because a large sterile tube with a funnel-like insert is indeed commonly used as a sputum collection system. This type of system helps to ensure that the sputum is collected in a clean and sterile manner, reducing the risk of contamination. The funnel-like insert helps to direct the sputum into the tube, making it easier to collect and transport for further analysis or testing. Overall, this type of collection system is widely used in healthcare settings for sputum collection.

Explanation
Rinsing the mouth with plain water before collecting a sputum sample is a common practice to reduce the number of oral bacteria present in the mouth. This is important because these bacteria can contaminate the sputum sample, leading to inaccurate test results. By rinsing the mouth, the patient can minimize the presence of oral bacteria and ensure a more reliable sputum sample for testing. Therefore, the statement is true.

Explanation
A sputum specimen may be canceled if there are too many oral bacteria present. This is because oral bacteria can contaminate the sputum sample, making it difficult to accurately diagnose any respiratory infections or diseases. Therefore, if there are too many oral bacteria present in the specimen, it may be deemed unusable and the test may need to be canceled or repeated.

Explanation
The criteria for urine for C&S testing include using a sterile cup to collect the urine sample, performing a midstream clean catch collection technique to minimize contamination, and using an aseptic collection technique to ensure a sterile sample. These criteria are important to prevent the introduction of bacteria or other contaminants into the urine sample, which could affect the accuracy of the culture and sensitivity testing.

Explanation
When transporting a liquid specimen like sputum for culture, the specimen should not be placed in the exact same compartment of the bag as the paperwork. This is because the specimen may leak or spill during transportation, potentially contaminating the paperwork and making it unreadable. Therefore, it is important to separate the specimen from the paperwork by placing it in a separate compartment or using a separate bag to ensure the safety and integrity of both the specimen and the paperwork.

Explanation
Cary Blair medium is a transport medium commonly used to preserve stool specimens for culture and sensitivity (C&S) testing. It contains a combination of ingredients that help maintain the viability of bacteria in the specimen during transportation to the laboratory. This allows for the isolation and identification of potential pathogens present in the stool, as well as testing their susceptibility to various antibiotics. Therefore, it is correct to say that stool specimens in Cary Blair medium can be used for C&S.

Explanation
Stool specimens in PVA (polyvinyl alcohol) and formalin are not suitable for culture and sensitivity (C&S) testing. PVA is used for preserving parasites and formalin is used for preserving tissues, but they are not appropriate for bacterial culture. Therefore, the statement is false.

Explanation
Stool specimens cannot be collected in the diaper of infants. This is because the diaper may contaminate the specimen with urine, making it unsuitable for accurate testing. Instead, a clean container should be used to collect the stool sample directly from the infant's diaper or from a potty chair.

Explanation
10% formalin and PVA (polyvinyl alcohol) are both commonly used preservatives for preserving stool samples for parasite examination. 10% formalin is a solution of formaldehyde gas dissolved in water, which helps to fix and preserve the stool sample by preventing decomposition and killing any parasites present. PVA is a synthetic polymer that forms a stable gel when mixed with water, which helps to preserve the stool sample by preventing dehydration and maintaining the structure of any parasites present. Cary Blair and C&S are not commonly used preservatives for stool samples in the context of parasite examination.

Explanation
The correct answer is both. Enterobius vermicularis, also known as pinworm, can be collected using both the microscope slide, tongue depressor, and cellophane tape system, as well as the perianal swab method. The tape system is commonly used to collect pinworm eggs by pressing it against the perianal area to pick up any eggs present. The perianal swab method involves swabbing the area around the anus to collect any pinworm eggs or adult worms. Both methods are effective in collecting Enterobius vermicularis for examination and diagnosis.