Shape: Cells can be round, oval, spindle-shaped, columnar, polygonal, etc. For example,
red blood cells are typically biconcave discs, while
neurons have a complex, branched structure.
Size: Cells vary greatly in size. Some, like bacterial cells, are only a few micrometers in diameter, while others, like
oocytes, can be several millimeters across.
Structure: The presence of specific organelles and structures, such as
nucleus,
mitochondria, and
cytoskeleton, also helps in classification.
