Fibrocytes—Fibroblasts , Purkinje Cells—Cerebellar Cortex, Vegetative Ganglion Cell
Fibrocytes—Fibroblasts In connective tissue sections, the nonmotile (fixed) fibrocytes look like thin, spindle-shaped elements. However, their true shape can be brought out in thin whole-mount preparations. Fibrocytes are sometimes rounded, sometimes elongated, flattened cells with membranous or thorn-like processes 1 . The cell processes often touch each other and form aweb. Their large, mostly oval nuclei feature a delicate chromatin structure (not visible in this preparation). Here, the nuclei appear homogeneous. Fibroblasts biosynthesize all components of the fibers and the extracellular matrix (ground substances). Fibrocytes are fibroblasts that showmuch lower rates of biosynthetic activity.
1 Fibrocytes with cytoplasmic processes 2 Nuclei from free connective tissue cells
Purkinje Cells—Cerebellar Cortex Pear-shaped Purkinje cells, which are about 50–70μm high and 30–35μm wide (cell soma, perikaryon) 2 , send out 2–3μm thick dendrites that branch out like trellis trees. These delicate trees reach up to the cortical surface, extending their fine branches espalier-like in only one plane. The axon (efference) 1 spans the distance between the basal axon hillock and the cerebellar cortex. The elaborate branching can only be seen using metal impregnation
1 Axon 2 Perikaryon
Oocyte Oocyte from a sea urchin ovary. Large, heavily stained nucleolus 2 inside a loosely structured nucleus 1 . The finely granulated cytoplasm contains yolk materials. Cell organelles are not visible 1 Nucleus 2 Nucleolus
Vegetative Ganglion Cell Large vegetative ganglion cell from the Auerbach plexus (plexus myentericus) from cat duodenum. A collateral branches from the upward extending axon. The downward-pointing cell processes are dendrites. Note the large nucleus
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