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You do a streak plate in order to get isolated colonies. If you inoculate into a slant, you have less surface area to work and less chance of getting isolated colonies. In broth, you'll definitely get growth but you won't know WHAT is growing. You go back into each quadrant (a little) with your loop in order to "dilute" the bacteria and get colonies. Quadrant 1 is pretty think (like a smear on the plate) but by the time you get to Quadrants 3 and 4, you should see more defined colonies and not just a film of bacteria.
What else can I help you with?
When would a microbiologist want to use the streak-to-grow method.?
Plate streaking is often done to isolate a colony of bacteria. For instance, if a broth was grown with 2 or 3 different types of bacteria, it could be streaked out in a "3-phase streak." In a 3-phase streak the initial streak takes up a very small area (we draw a T on the back of the plate, this streak goes in the section above the T). The loop is flamed to kill off any bacteria still on it, then a couple streaks are made out of the original. This grabs some of the bacteria from that concentrated streak and spreads them out. This is repeated once more until the final streaks are less and less concentrated bacteria. When we incubate the plate we'll find lots of growth where the original streak was and less and less as we follow the path of the 3-phases. What you're looking for now is a single colony, off by itself. This can then be scraped off and plated on a separate plate and considered a "pure colony." Another usual time to use streak-to-grow bacteria is when you want to know the quantity or concentration of bacteria. You take maybe 0.1mL of solution and plate it, then count the number of colonies that form. Say you have 56 colonies, now you can say: 56 cfu (colony forming units) -------- 0.1 mL or 560 cfu/mL This is usual when testing to see whether a sterilization technique worked, or if a product is within the regulated levels of bacteria to be released the public, etc etc.
Why do you use streak plates?
Streak plates are used in microbiology to separate and isolate individual bacterial colonies from a mixed culture. By streaking a bacterial sample across the plate in a specific pattern, it allows for the dilution and separation of cells, making it easier to identify and study individual colonies.
What factors would account for an absence of growth on a streak plate?
Possible factors that could account for an absence of growth on a streak plate include insufficient nutrient availability, improper incubation conditions such as incorrect temperature or atmosphere, presence of antimicrobial agents, or the use of an incorrect type of agar medium that does not support the growth of the organism being tested.
What advantage does the streak plate method have over the pour plate method?
A disadvantage of the streak plate technique could be colony isolation problems. If the streaking technique is not done properly or if there is too much of an organism present on the inoculating loop then the cells can cluster and form what looks like one colony but it can actually be a couple colonies (made from a couple cells). This can cause an inaccurate colony forming unit count.
How could you identify a potential contaminant on a streak plate?
To clean a streak plate I use coke classic. In the red can, the diet version does not work as well. I believe it is the acid that takes away the powdered rock debris. It makes them quite white again. Mr clean magic eraser also takes away some of the heavy debris...but does not get them clean enough.
List two methods for obtaining isolated colonies.?
Use a "streak plate" or a "spread plate". Mediums that allow some organisms to grow and not others can also be used. These types of mediums are called Selective medium.
How is a minterals streak determinded?
Streak color is determined by scraping the mineral across a a streak plate, (which is made of unglazed porcelain), and then observing the color of the streak, which is left on the plate. Note that some minerals do not leave a streak, as they are too hard. Thus, it is important to learn other identification methods, to use in conjunction with streak color, in order to identify minerals.
What does a mineral and streak tell you and how do you test for it?
The streak of a mineral can distinguish between two samples that have the same color. The streak is often a different color. To test streak, use a streak plate. This is a piece of unglazed porcelain, like the back side of a tile.
What does a mineral's streak tell and how do you test for it?
The streak of a mineral can distinguish between two samples that have the same color. The streak is often a different color. To test streak, use a streak plate. This is a piece of unglazed porcelain, like the back side of a tile.
If you were given a tube with 3 different bacterial species in it what is the first thing you would do to separate the three?
The best thing to do is get a nutrient agar plate and spread the bacteria using a streak-plate method of isolation to grow the different colonies individually. (And you could do a second streak-plate from each type of colony you see just to make sure that your colonies each contain only one type of bacteria.) From there you can identify and grow each pure culture. (Also, you could use selective medias.)
How does the contribution of growth on a pour plate different from that on a steak plate?
Colonies growing on a pour plate have slightly less avalible oxygen and are confined by the gel matrix so they tend to grow smaller than those on a pour plate. Streak plates are use to isolate single colonies, pour plates are used to enumerate batceria.
What does mineral's streaks tell you and how do you test for it?
The streak of a mineral can distinguish between two samples that have the same color. The streak is often a different color. To test streak, use a streak plate. This is a piece of unglazed porcelain, like the back side of a tile.
How do you know a mineral's streak?
The streak of a mineral can distinguish between two samples that have the same color. The streak is often a different color. To test streak, use a streak plate. This is a piece of unglazed porcelain, like the back side of a tile.
What is the significance of using a 'dry and hard' agar plate in streak plating?
Why is it impotant to use dry and hard agar for streaking
Would the streak of garnet be difficult to determine?
Determining the streak of garnet can be challenging because it varies depending on the specific type of garnet. In general, garnet typically has a white streak, but some varieties may leave a slightly different colored streak due to impurities. It's best to use a streak test plate to compare and determine the actual color of the streak.
How do you label streak plates?
To label streak plates, use a marker or pen to write the sample name, date, and any other relevant information on the bottom of the plate. Place the label in an area that will not interfere with streaking the sample on the plate. It's important to use a permanent marker to ensure the label stays on throughout the experiment.
When would a microbiologist want to use the streak-to-grow method?
Plate streaking is often done to isolate a colony of bacteria. For instance, if a broth was grown with 2 or 3 different types of bacteria, it could be streaked out in a "3-phase streak." In a 3-phase streak the initial streak takes up a very small area (we draw a T on the back of the plate, this streak goes in the section above the T). The loop is flamed to kill off any bacteria still on it, then a couple streaks are made out of the original. This grabs some of the bacteria from that concentrated streak and spreads them out. This is repeated once more until the final streaks are less and less concentrated bacteria. When we incubate the plate we'll find lots of growth where the original streak was and less and less as we follow the path of the 3-phases. What you're looking for now is a single colony, off by itself. This can then be scraped off and plated on a separate plate and considered a "pure colony." Another usual time to use streak-to-grow bacteria is when you want to know the quantity or concentration of bacteria. You take maybe 0.1mL of solution and plate it, then count the number of colonies that form. Say you have 56 colonies, now you can say: 56 cfu (colony forming units) -------- 0.1 mL or 560 cfu/mL This is usual when testing to see whether a sterilization technique worked, or if a product is within the regulated levels of bacteria to be released the public, etc etc.
