In this video, we're going to begin our introduction to the cytoskeleton. The cytoskeleton, as implied by the cyto prefix, is a network of elongated proteins that are found in the cytoplasm of a cell, and it has multiple different functions. Also implied by the term cytoskeleton, it resembles our own skeletons. Just like our skeletons give our bodies their shape and structure, the cytoskeleton of cells does something similar; its functions include providing cell shape, as well as cell structure. Once again, we know that the cytoskeleton has multiple different functions. Not only does it provide the cell with its shape and structure, but it's also very important for cell movement, transportation, and bio signaling as well.
There are 3 major components of the cytoskeleton, which are the microfilaments, the intermediate filaments, and the microtubules. The microfilaments are the smallest component of the cytoskeleton. They are made up of thin rods of repeating actin proteins. Actin is the name of a protein that will repeatedly come together to build microfilaments. The intermediate filaments, as their name implies, are intermediate in size, being larger than microfilaments but smaller than the microtubules. They are made of a variety of different types of proteins. The microtubules, on the other hand, are the largest component of the cytoskeleton. They form large tubes made up of repeating tubulin proteins.
Let's take a look at our image below to get a better idea of this cytoskeleton. Notice that we're saying that the cytoskeleton has somewhat of a resemblance to our own skeletons. Through fluorescence microscopy, we can actually turn components of the cytoskeleton different colors, just like you can see in this image where the skeleton hand is having different colors. Over on the far left, we're showing you the microfilaments. In this image, the components of the microfilaments are colored in red. They are found throughout the cytoplasm of the cell and have the smallest diameter. Next, we have the intermediate filaments here in the middle; they are intermediate in size and shown in green. The microtubules, which are the largest in size, come together to form a large tube also shown in green in this image.
The cytoskeleton fills up the entire space of the cytoplasm of a cell. It plays very important roles in providing the cell its shape, its structure, providing movement, transportation, and bio signaling. This concludes our introduction to the cytoskeleton, and we'll be able to apply these concepts as we move forward in our course. I'll see you all in our next video.