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You first inoculate your loop with bacteria and streak a few times across your plate, heat your loop on a bunsen

burner to sterilize it and let the loop cool to. Bring your loop back onto where you previously streaked a few times swiping back and forth....heat

loop again to sterilize and let it cool. Then the last and third time take your inoculating loop back on where you streaked last time back and forth a few time across the plate always turning your plate 90 degrees. Always remember to stay close to the bunsen

burner so you are in the sterile area of the flame to prevent any unwanted contamination of your bacteria. After your media is incubated you should notice 3 streak marks and the third streak mark should be the most dilute where the bacterial colonies are separate and easily observed and can be used further, if needed.

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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.


Why use a streak plate to grow a bacterium?

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 are the differences between streak plate technique and pour plate technique?

Streak Plate:Pure colonies of bacterial or other microorganisms can be obtained on petri dishes by streak plate. The microbial mixture is transfered to the edge of an agar plate with an inoculating loop or swab and then streaked out over the surface in one of several patterns. After the first sector is streaked in dish, the inoculating loop is sterlized and an inoculum for the second sector is obtained from the first sector. The same is done for third and fourth sector. Thus this is a dilution process. Eventually, very few cells will be on inoculating loop, a single cells will drop from it as it is rubbed along the agar surface. These develop into seprate colonies.Pour Plate:Extensively used with procaryotes and fungi, a pour plate also can yield isolated colonies. The original sample is diluted several times to reduce the microbial population sufficiently to obtain separate colonies when plating. Then small volumes of several diluted samples are mixed with liquid agar that has been cooled to about 45oC and the mixture are poured immediately into sterile culture dishes. Most bacteria and fungi are not killed by a brief exposure to the warm agar. After the agar has hardened each cell is fixed in place and forms an individual colony.


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.


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.

Related Questions

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.


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 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.


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.


Why use a streak plate to grow a bacterium?

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.


How do you use the word microbiology in a sentence?

I can not use microbiology in a sentence.


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.


What are the differences between streak plate technique and pour plate technique?

Streak Plate:Pure colonies of bacterial or other microorganisms can be obtained on petri dishes by streak plate. The microbial mixture is transfered to the edge of an agar plate with an inoculating loop or swab and then streaked out over the surface in one of several patterns. After the first sector is streaked in dish, the inoculating loop is sterlized and an inoculum for the second sector is obtained from the first sector. The same is done for third and fourth sector. Thus this is a dilution process. Eventually, very few cells will be on inoculating loop, a single cells will drop from it as it is rubbed along the agar surface. These develop into seprate colonies.Pour Plate:Extensively used with procaryotes and fungi, a pour plate also can yield isolated colonies. The original sample is diluted several times to reduce the microbial population sufficiently to obtain separate colonies when plating. Then small volumes of several diluted samples are mixed with liquid agar that has been cooled to about 45oC and the mixture are poured immediately into sterile culture dishes. Most bacteria and fungi are not killed by a brief exposure to the warm agar. After the agar has hardened each cell is fixed in place and forms an individual colony.


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.