Final answer:
Reticular fibers provide structural support to cells in soft organs like the spleen, lymph nodes, and the liver. They form a mesh-like framework vital for the function of these organs and are produced by reticular cells.
Step-by-step explanation:
The fibers that provide structural support to cells in organs such as the spleen, lymph nodes, and the liver are known as reticular fibers. These fibers are a component of reticular tissue, a type of loose connective tissue. Reticular fibers are composed of protein subunits similar to those of collagen fibers but are finer and form a complex branching network.
Reticular fibers are produced by reticular cells and create a mesh-like structure that not only anchors other cells but also aids in filtration and immune response functions. For example, in the spleen, reticular fibers are part of both red and white pulp regions, where they support blood-filtering macrophages and immune response sites, respectively. This structural framework is essential for the spleen's role as a blood filter and an immune organ.