Okay, so imagine making cookies. You know how you mix all the ingredients like flour, sugar, eggs, and butter? Well, sometimes when you make something that needs to grow or multiply, like yeast in bread or cells in a lab, you can't just mix everything together at once or it won't grow properly. Instead, you add a little bit of each ingredient at a time, and let it grow before adding more.
That's what fed-batch means - you add more ingredients, or "feed" the mixture, over time, instead of all at once. In a lab, scientists use fed-batch methods to grow cells or bacteria for experiments. They start with a small amount of cells or bacteria and add more nutrients or food every once in a while so that the cells can grow and multiply without running out of resources.
By using fed-batch, scientists can control how many cells they get at the end, and make sure they grow in a healthy way. Just like how you need to make sure your cookies don't burn in the oven or your bread doesn't come out too flat, scientists need to monitor the fed-batch process to make sure everything is going how it should.
So, in short, fed-batch is a way of slowly adding ingredients or food over time to help cells or bacteria grow and multiply properly, and it helps scientists control the growth and health of these organisms in the lab.