question about generation and passage? - (May/25/2005 )

Hi:

i am puzzled with the difference of generation and passage.

usually, when the culture was subcultured once it is called one passage.

how about the concept of generation.

furthermore, what is the difference of generation time and population doubling time?

thanks!

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passage and generation are the same things. when the cells have doubled once then it is one generation. when they double twice then it is two generations. generation time and population doubling time are the same thing. it is the time where a specific type of cells double. this time makes the exponential phase of the cell cycle.

correct me if i am wrong.

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I agree - as far as i know, they're the same thing

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I don't agree. One passage means that the cells grow to confluence in a culture vessel before subculture......
You can have cells going for 2-3 generations (population doublings) then start to passage them. So, that's 2-3 generations in 1 passage!!!

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I agree with joy_maf, you can have more than one generation per passage, depending on seeding density. If you seed at a density less than 50% cover (and most people do, usually seeding is below 25%), then you will get more than one generation before the cells need to be passaged.

Bob

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