 Hey everybody, Dr. O here. In this video I want to talk about generation time. So we mentioned it in the video where we talked about bacterial population growth curves, but the generation time is how long it takes for a bacterial cell to divide and their population to double. Because as you can see here, one becomes two, two becomes four, four becomes eight. So why is this important to know? Number one, it tells you how quickly an organism is going to grow, which means how quickly it might reach its infectious dose or something like that. And also it's nice because it helps you understand if our control agents are working. So if a generation time is doubled, that means that a preservative or a control agent is doing its job. It's slowing bacterial population. So I'm going to give you some numbers really here just to kind of blow your mind. But understand this would be if there was nothing inhibiting the growth of microbes. So this would be what's called in biology classes called your biotic potential. How quickly could a population grow if there were no limiting factors? Nothing was slowing it down. Obviously that doesn't happen or else we'd be living on a planet that's covered with bacteria a mile deep. But the average bacteria is going to have a generation time in the one to three hour range, some much longer, some take more than a day. The real slow growing microorganisms and others are going to be quite a bit shorter. So for example, E. coli's generation time is usually considered 20 to 21 minutes in an optimal environment at the right temperature and everything else. So assuming E. coli has a generation time of 20 minutes, let's do a little bit of, let's play with some numbers here. That means that in about 400 minutes, one cell would become a million. So one E. coli could lead to or generate a million new E. coli. In 10 hours, which would be 30 of these generations, you'd now be at a billion. So in slightly less than six hours to 10 hours, you jumped from a million to a billion. But then in 24 hours, you would actually reach a number that has 21 zeros behind it. I have in the slightest idea what that number is, but it's just that's how big it is. And then an example we've shared earlier, in 25 and a half hours, I won't give you a number, but a weight. You would have a pile of E. coli that weighs 80,000 tons. So think about that. How quickly one cell can become a million, a billion, and then whatever in the world these huge numbers are. So that's what generation is. That's kind of why it's important. And then it is pretty mind boggling. But of course, keep in mind that this doesn't happen. This is optimal conditions where they never run out of food. They never run out of space. And their waste products are removed in a way where they continue to grow and grow without poisoning themselves, without altering the pH. So all right, that's generation time. Have a wonderful day. Be blessed.