In this video, we're going to begin our lesson on growing a pure culture. And so in a scientific lab or a microbiology lab, bacterial and archaeal cells are generally isolated, grown, and studied in what's known as a pure culture. And so a pure culture can be defined as a population of cells containing only one single species. And typically, these pure cultures are grown starting from a single colony. Now, a colony is a scientific term that's used to describe a group of approximately 1,000,000 cells or so. And colonies are going to be required to start a pure culture. And these pure cultures are again typically grown in a lab. And so if we take a look at our image down below over here at this pure culture, notice that we're starting with just a single bacterial cell over here. And this single bacterial cell will divide and replicate in order to create many more cells of the same exact species. And so we have a population of cells here, but this population of cells consists of just one single species. And because we have a lot of cells here, if we had about 1,000,000 cells or so, we would have ourselves a colony of cells or a group of cells that are all the same species. And so this is an example of a pure culture because it is a population of cells containing only one species. And so, notice here that this old guy over here saying, 'Look at all my children' and these guys are saying 'We form a colony together' and all cells are going to be descended from a single cell in a pure culture. That is what allows for the population of cells to only contain 1 single species. Now, there is another term here that might be important to keep in mind if you're in a microbiology lab and that is the term inoculum. And so an inoculum is really just a colony of cells that are added to a culture medium in order to start a pure culture. And so if we wanted to create a pure culture, what we would typically do is start with a colony of cells that are all of a single species, and then we would use that colony as an inoculum to inoculate growing a pure culture, and we'll be able to get some practice applying these concepts as we move forward. So I'll see you all in our next video.
10. Dynamics of Microbial Growth
Growing a Pure Culture
10. Dynamics of Microbial Growth
Growing a Pure Culture - Video Tutorials & Practice Problems
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concept
Growing a Pure Culture
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Video transcript
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Problem
ProblemA pure culture of bacteria is made of…
A
Around 1 million viable bacteria cells that are all of the same species.
B
Around 1 million viable bacteria cells that are all descended from a single parent cell.
C
Around 1 million viable bacteria cells that are a mixture of different bacterial species.
D
Both A and B.
E
Both A and C.
F
Both B and C.
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Problem
ProblemA bacterial culture grown in a _________________ will not continue to grow exponentially forever, but will stop once the limited nutrients have been consumed.
A
Open system.
B
Secure system.
C
Closed system.
D
Extended system.
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PRACTICE PROBLEMS AND ACTIVITIES (4)
- Match the following choices to the culture descriptions in questions 3 through 6:a. Chlamydiab. Coccidioidesc....
- Match the following choices to the culture descriptions in questions 3 through 6:a. Chlamydiab. Coccidioidesc....
- Match the following choices to the culture descriptions in questions 3 through 6:a. Chlamydiab. Coccidioidesc....
- “In the laboratory, a sterile inoculating loop is moved across the agar surface in a culture dish, thinning a ...