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1 how are microorganisms diluted and spread out to form individual colonies In the streak plate technique?
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Bacterial mixture is transferred to the edge of an agar plate with an inoculating loop and then streaked out in one of several patterns. At some point, individual cells will be removed from the loop and will give rise to separate colonies.
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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.
Will isolated colonies of bacteria always be in the fourth sector on the streak plate?
No, of course it is possible that one could start out with an already diluted sample in the first step. So then perhaps in the third sector some isolated colonies may form, because the amount of bacteria have been diluted enough.
Under what kind of plating technique would you find deep or buried colonies?
In pour plate method, in this method of plating or culturing the microbial sample first diluted and pour in empty plate and after that growth media is poured in it and which is then skake firmly. As the microbial suspension or sample is distributed in media the growth of bacteria occurs in buried of deep positions.
What are the Different methods used to isolate microorganisms?
1 The Spread Plate: If a mixture of cells is spread out on an agar surface so that every cell grows into a completely separate colony, a macroscopically visible growth or cluster of microorganisms on a solid medium, each colony represents a pure culture. The spread plate is an easy, direct way of achieving this 2 The Pour Plate: Extensively used with bacteria 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 result. 3 The streak plate: Pure colonies also can be obtained from streak plates. The microbial mixture is transferred to the edge of an agar plate with an inoculating loop or swab and then streaked out over the surface in several patterns
What is the importance of a pour plate in microbiology?
Extensively used with procaryotes and fungi, a pour plate can yield isolate colonies. The original sample is diluted several times to reduce the microbial population sufficiently to obtain seprate colonies when plating. The pour plate can be used to determine the number of cells in a population.
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.
Advantages of pour plate method over other methods of bacterial colony?
The purpose of the spread-plate technique is to grow and isolate colonies of bacteria. A sample of bacteria is transferred to the agar plate, an environment that provides nourishment for the bacteria to grow. The bacteria sample is applied to the agar plate which a special streaking technique that dilutes the amount of bacteria in each section of the agar plate continuously. This is because if you just swabbed the bacteria onto the plate with no special technique the colonies would grow very densely together and be difficult to study. The streaking technique gradually dilutes the amount of bacteria in each 'quadrant' of the plate, so the last quadrant should have small, isolated colonies that can be easily studied. The spread plate technique is also used for the eneumeration of aerobic microorganisms from the given sample. This can be done by serial diluting the samples, placing 0.1ml of the diluted sample in the middle of an agar plate and spreading the sample over the surface with a help of an L-rod. After the incubation rhe colonies can be counted.
Will isolated colonies of bacteria always be in the fourth sector on the streak plate?
No, of course it is possible that one could start out with an already diluted sample in the first step. So then perhaps in the third sector some isolated colonies may form, because the amount of bacteria have been diluted enough.
Why it necessary to use only diluted cultures that contain 100 to 200 cells for a successful plate counting?
It is necessary to use only diluted cultures that contain 100 to 200 cells for a successful plate counting because above that the colonies will be too dense on the plate and counting them will be difficult. Also, many of the colonies will merge.
Under what kind of plating technique would you find deep or buried colonies?
In pour plate method, in this method of plating or culturing the microbial sample first diluted and pour in empty plate and after that growth media is poured in it and which is then skake firmly. As the microbial suspension or sample is distributed in media the growth of bacteria occurs in buried of deep positions.
Determine the population of bacteria based on the bacterial colonies?
Assume each colony started as a single bacteria in the original culture. Count the colonies you have and multiply up according to how diluted you made the culture and how much of the original culture you used.
What happens when you swallow an acid what happens to your stomach acid?
it is diluted Edited: It is NOT diluted. It is neutralized.
What are the Different methods used to isolate microorganisms?
1 The Spread Plate: If a mixture of cells is spread out on an agar surface so that every cell grows into a completely separate colony, a macroscopically visible growth or cluster of microorganisms on a solid medium, each colony represents a pure culture. The spread plate is an easy, direct way of achieving this 2 The Pour Plate: Extensively used with bacteria 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 result. 3 The streak plate: Pure colonies also can be obtained from streak plates. The microbial mixture is transferred to the edge of an agar plate with an inoculating loop or swab and then streaked out over the surface in several patterns
Why should you use the wafting technique to smell chemicals?
Safety - getting a lung full of a possibly toxic chemical is never good. Wafting means you get a gentle smell diluted with plenty of air.
What is diluted liquid antibacterial soap?
diluted liquid antibacterial soap is usually a soap that has a smaller proportion of cleaning agent in it's formula. Often times for children or those with sensitive skin, though the antibacterial agent is generally full strength(if it is not the soap would do well to destroy bacterial colonies)
Will isolated colonies always be in the second sector on the streak plate?
No. It depends on the number of bacteria present in the initial sample. If the number of bacteria in the initial sample are limited, you may get isolated colonies in the first streak. If the number of bacteria in the sample are high, it may take several streaks before the sample is diluted to the point where isolated colonies are evident.
Why can't animals live in the Dead Sea?
Because the salt content would dehydrate fish and higher animals. The lake has some microorganisms that can tolerate the salinity when it is diluted by rainwater. These include the algae Dunaliella and bacteria that feed on it.
