hello and welcome to another episode of interactive biology TV where we're making biology fun my name is lesie Samuel and in this episode I'm going to be talking about the four types of cellular adaptations now two videos ago I answered the question what is a disease and in the last episode what I spoke about were the five causes of disease and the first cause the number one cause of disease was adaptation and what I said was that an adaptation is a cellular reaction to prevent injury so there is an injurious agent in the environment of the cell and the cell reacts in a way to prevent injury you can go back and check out those videos but in this video what I want to talk about is the first cause of disease which is an adaptation so what we going to do is we're going to talk about the four types of adaptations adaptation number one is atrophy atrophy is when uh the cell decreases its functional Parts the the cell is basically reducing its size by decreasing its functional parts that's number one number two is hypertrophy and that is when the the individual cells increase in size and that of course is going to cause the tissue to increase in size size then there's hyperplasia hyperplasia is when we have more cells being formed so the cells are replicating and as a result of that the tissue is increasing in size so with hypertrophy hypertrophy we have the the tissue increasing in size because the individual cells are increasing in size in hyperplasia we have the tissue increasing in size because we're getting more cells which makes sense and then the last type of adaptation will be metaplasia and that is when we have one tissue type that's replaced by another tissue type so these are the four types of adaptations I'm going to go into more detail about those adaptations in later videos but for this video all I want you to be able to do is remember those four adaptations number one atrophy then hypertrophy hyperplasia and metaplasia and you can say it with me let's say it together so number one is atrophy hypertrophy hyperplasia and metaplasia we can kind of say it together almost we can almost dance to it it's it's that simple so atrophy hypertrophy hyperplasia and metaplasia atrophy hypertrophy hyperplasia and metaplasia in the next video we're going to go into detail about atrophy and we're going to continue from there that's it for this video if you want more video like this and more resources to help make biology fun I invite you to visit the website at interactive D biology.com that's it for this video and I'll see you in the next one