Final answer:
Intermediate filaments such as keratin and desmin provide structural support within cells and in larger structures like skin, hair, and muscles, and lamins form the nuclear lamina supporting the cell nucleus.
Step-by-step explanation:
Intermediate filaments are a critical component of the cytoskeleton, providing structural support for cells. These fibrous proteins have a prominent role in maintaining cell shape, anchoring organelles, and forming resilient structures throughout the body.
Their robust nature allows them to withstand tensile forces, opposing cellular deformation under stress. For instance, the intermediate filament type known as keratin is abundant in the epithelial cells of the skin and is also the primary component of hair, nails, and the epidermis - fortifying these structures. Inside cells, keratin-based intermediate filaments attach to desmosomes, tying cells together and conferring durability to tissue subjected to mechanical stress. Another type of intermediate filament, desmin, is critical in muscle cells where it links to Z-disks or cell membranes, playing a significant role in transmitting contractions.
In the cell nucleus, intermediate filaments made of lamins contribute to the composition of the nuclear lamina, providing a skeletal framework that supports the nuclear envelope. This diverse group of proteins strategically contributes to the cell's integrity and resiliency, fundamental for tissue and organ function.