Species: Mouse (Mus musculus; mammals).
Technique: 8 µm thick paraffin sections stained with haematoxylin and eosin.
The loose connective tissue shows a highly developed and extracellular matrix. The ground substance is prominent in the extracellular matrix, that is why the clear appearance. There are also collagen fibers and elastic fibers, as well as reticular fibers in some tissues. In the image above, elastic fibers can be readily observed, which are long and thin, whereas collagen fibers are shorter and thicker. Collagen fibers are much less abundant than in other connective proper tissues (for instance irregular dense connective tissue).