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To calculate the bacteria per milliliter (ml) in a contaminated urine specimen, first, perform a quantitative culture by diluting the urine sample and plating it on an appropriate agar medium. After incubation, count the number of colonies that grow on the plate. Multiply the number of colonies by the dilution factor and the volume of the plated sample (in ml) to determine the concentration of bacteria per ml in the original urine specimen. For example, if you plated 0.1 ml of a 1:100 dilution and counted 50 colonies, the calculation would be 50 colonies × 100 (dilution factor) × 10 (to convert 0.1 ml to 1 ml), resulting in 50,000 bacteria/ml.
What else can I help you with?
Why does Pepto-Bismol turn black when you mix it with contaminated water?
Pepto-Bismol is made with bismuth subsalicylate, which can react with sulfur compounds present in contaminated water to form bismuth sulfide. This chemical reaction causes the mixture to turn black.
Why is typhoid caused by drinking unhygienic water?
Typhoid fever is caused by bacteria present in contaminated water. Water is contaminated by exposure to feces of effected person . It is common in poor countries with little hygienic care and poor sanitary conditions .It effects intestine hence called enteric fever .
What is the purpose of negative staining experiment?
Answer by NO.1GreatThinker :- The basic purpose of the negative staining experiment is to check out the bacteria / micro-organisms which have less amount of peptidoglycans present in their cell wall So experiment can be performed to distinguish gram negative bacteria from gram positive one . It is performed by using a dye nigrosin which is a negatively charged dye in nature . So it is first taken on a slide ( just a drop of it ) . Then specimen of the bacteria is taken from the culture . It is placed over the dye . Now since bacteria is also negatively charged . So there is repulsion in both dye and the bacteria . Hence the bacteria seems or appears in between the dye as bright light spots . It is observed under the light microscope . Hence the experiment .
What bacteria is found in beef?
Beef can be contaminated with several types of bacteria, with Escherichia coli (E. coli), particularly the strain O157:H7, and Salmonella being among the most common. Other bacteria such as Listeria monocytogenes and Campylobacter can also be present. These pathogens can cause foodborne illnesses if the beef is not cooked or handled properly. Proper cooking and food safety practices are essential to minimize the risk of infection.
Can colony morphology help to determine the identity of bacteria?
to know the amount of bacteria present
What are medically important bacteria often grown on?
The only culture medium I know are called petri dishes. The bottom is coated with a media that encourages growth, if any bacteria are present in the specimen. The petri dish remains covered/closed and placed in an area that incubates the specimen. IF bacteria are present, it will grow and multiply into colonies often big enough to see with the naked eye, i.e. without a microscope.
Why are blood cultures drawn from two different sites?
If one produces bacteria and the other doesn't, it's safe to assume that the bacteria in the first culture is contaminated, most likely with skin bacteria, and not the infecting agent. When both cultures grown the infecting agent, bacteremia is present.
Why does Pepto-Bismol turn black when you mix it with contaminated water?
Pepto-Bismol is made with bismuth subsalicylate, which can react with sulfur compounds present in contaminated water to form bismuth sulfide. This chemical reaction causes the mixture to turn black.
How do eggs get contaminated with salmonella?
Eggs can become contaminated with Salmonella during the egg production process, particularly if hens carry the bacteria in their ovaries or intestines. The bacteria can be present on the eggshell or inside the egg if the hen is infected. Environmental factors, such as poor sanitation, can also contribute to contamination. Proper handling and cooking of eggs can significantly reduce the risk of salmonella infection.
What time of day is best to collect a sputum specimen?
The best time to collect a sputum specimen is typically in the morning, shortly after waking up. This is because mucus accumulates overnight, making it easier to obtain a more concentrated and representative sample. Additionally, collecting the specimen at this time can help ensure it contains cells and bacteria that may be present in the lower respiratory tract.
What happens if bacteria is present in mouth?
Bacteria is always present in the mouth.
Why is typhoid caused by drinking unhygienic water?
Typhoid fever is caused by bacteria present in contaminated water. Water is contaminated by exposure to feces of effected person . It is common in poor countries with little hygienic care and poor sanitary conditions .It effects intestine hence called enteric fever .
Will contaminated food always have the same signs?
No. Food can be contaminated with a variety of adulterants - most of which show no signs at all that they are present.
What cause bacteria in your household?
Bacteria are present EVERYWHERE
How many good bacteria are present in the human body?
There are trillions of good bacteria present in the human body.
How soon must a urine specimen reach the laboratory?
How soon a specimen of something must reach the laboratory depends partly on the reason for which it is being sent to the laboratory, environmental conditions during storage and transit, and the stability of the substances the specimen consists of. A urine specimen must be refrigerated during storage and transit and arrive in the lab within an hour or two. It cannot sit out because warmth will allow bacteria, if present, to begin to grow in numbers.
How can you tell a specimen is a eukaryote?
By observing its organells. If a nucleus or membranous organelle present
