4-15 Connective tissue

RESIDENT CELLS OF THE CONNECTIVE TISSUE
FIBROBLAST – 2

Three fibroblasts located between collagen fibers are shown in this image.
They have have numerous long, slender, and sometimes tortuous cytoplasmic extensions. After hematoxylin and eosin (H&E) staining, the cytoplasm takes up a color similar to that of the collagen fibers The cytoplasm and its extensions are easier to observe with electron microscopy. With a light microscope, usually only a small portion of the cytoplasm is visible.
In connective tissue, fibroblasts can usually be recognized by their slender nuclei with rounded ends.

When you move the cursor over the image or click on it, the cytoplasm of the fibroblasts is highlighted in light gree, while their nuclei are highlighted in gray.
The fibroblast oriented vertically is particularly easy to identify because both its nucleus and cytoplasm are visible. Its nucleus is elliptical and has rounded ends.
Another fibroblast is located immediately to the right. Its nucleus is angled, but its cytoplasm is not visible.
The third fibroblast is located in the lower-left corner of the image. Its nucleus is clearly visible, but only a very small amount of its cytoplasm can be seen.