To avoid killing the test subjects before the test can begin.
Some other inoculating instruments include loops, spreaders, swabs, and pipettes. These tools are used to transfer and spread microorganisms onto various growth media for cultivation and observation in laboratory settings.
There will never be a pure culture in this system of things. However, depending on what you believe in of course, there is to come a time when all the disturbing mixed up things we deaql with on a daily basis will come to pass and a new earth will form. It will be at that time when we can truly obtain a pure culture. Just my opinion, take it for what it is, but know I'm basing it on over 30 years of theocratic study. Have a blessed day. ^ This person is a retard, it's a microbiology question, they aren't referring to a culture of people, they are referring to a culture of microbes. And it took me 2 seconds to look up the real answer. So: A mixed culture is a mix of different strains of an organism / bacteria. A pure culture is a culture consisting of only one strain. YOU CAN OBTAIN A PURE CULTURE BY PICKING OUT A SMALL PORTION OF THE MIXED CULTURE(which will form the pure culture) AND GROWING THEM ON A NEW CULTURE MEDIA. It's like taking 2 animals out of a herd and breeding them, and breeding only within their family, so they all look exactly the same. Except bacteria can reproduce asexually so you just need one.
The spreader can be cooled by putting in alcohol (70% ethanol) which can also sterlize it, but it should be avoided to put the spreader instantly in the alcohol as it can be break if made of glass rod so do it when spreader is not to hot.
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.
Yes, water expands when cooled below 4 degrees Celsius due to the formation of hydrogen bonds in its molecular structure. This expansion causes water to become less dense and eventually freeze into ice at 0 degrees Celsius.
To avoid killing the test subjects before the test can begin.
The inoculating tube is cooled before use so that the organism is not killed by extensive heat.
The purpose of heating the inoculating materials before and after using them is for sterilization. They must be sterilized before to kill any bacteria already on them so that they do not contaminate anything during use, and they must be sterilized after to get off the bacteria contacted from use.
Because too much heat can kill bacteria. Think of pasteurised milk - the pasteurising process involves rapid heating and cooling to kill off any bacteria that might be present in the milk.
To minimise condensation on the lid of the Petri dish.
In pour plate technique the culture to be grwon is pour in melted agar medium, now when we add the diluted sample in agar plate and if the melted agar is very hot, it can lead to the damage of bacterial or fungal cell and may cause in abruption of growth, so the agar is cooled to get the optimum temp. for growth of microbial cell.
Some other inoculating instruments include loops, spreaders, swabs, and pipettes. These tools are used to transfer and spread microorganisms onto various growth media for cultivation and observation in laboratory settings.
Because it is. face it
Tar is heated so it can stick to what ever it is going on. If it was cooled it would not stick right.
cause that makes it taste better
jjgg
It is hot and must be cooled before consumption.