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070 What is a Disease

070 What is a Disease

As promised, here is the start of a set of new videos to be uploaded to the site. Let’s start off this year by learning what a disease is from a Biological perspective.

Also, you’ll notice something new with the video format. Let me know what you think.

Have fun!

Transcript of Today’s Episode

Hello and welcome to another episode of Interactive Biology TV where we’re making Biology fun. My name is Leslie Samuel and in this episode, Episode 070, I’m going to be answering a simple question, What is a disease? I know what you’re thinking. Everybody knows what a disease is. But, since this Interactive Biology, we’re going to look at it from a Biological perspective. So, let’s get right into it.

A disease is an abnormal condition that affects the body of an organism.

What’s an organism? An organism is a living thing. And, when we’re talking about Pathology, or Pathophysiology, we’re talking about human beings. So, we’re talking about an abnormal condition that affects the body of a human being. A disease is usually associated with a number of symptoms or signs. But, what does these all really means?

Okay, so we have an abnormal condition affecting the body. But, what is the body? I know what you’re thinking, the body of a human being is made up of systems. So, we have the circulatory system, we have the muscular system, the skeletal system, the urinary system, all of these different systems that come together to form a human being.

But, what are these systems? I know what you’re thinking now. You’re thinking these systems are made up of organs, and you’re right! For example, the circulatory system is made of the heart, and the blood vessels and all these things come together to form the circulatory system.

But, what is an organ? I know what you’re thinking because you’re smart. An organ is made up of tissues. All right, so we have it down to the tissue level. But, what is a tissue? Finally, you’re there. A tissue is made up of cells. All living things — human, or dog, or cat, or wolf, whatever it is, all living things are made up of cells.

So, if you have an abnormal condition that affects an organism, that’s because we have something that’s affecting one or more of the organ systems. And then, of course, it’s affecting one or more of the organs, one or more of the tissues, and one or more of the different cell types. So, in essence, what we’re saying is, if we have a disease, we have an abnormal cellular structure, and/or function, there is something wrong at the cellular level that’s causing this thing to be manifested on the level of the organism.

Now, there are many different types of diseases. But, I’m going to tell you something that’s going to make it much more simple. All of these disease can be attributed to one of five causes. Doesn’t that sound simple? If we know these five causes, we could explain to some level every single disease that’s out there.

What are those five causes? That’s what we’re going to talk about in the next episode.

That’s all for this episode. Once again, I want to invite you to come back to the website at, where you’re going to find more videos just like this, and many other resources to help you make Biology fun.

By the way, what do you think about this new video format? Let me know in the comments below. That’s it for now, and I’ll see you in the next video.

About The Author

Leslie Samuel

Leslie Samuel is the creator of Interactive Biology. His mission is to use this site to Make Biology fun for people all over the world.

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