Specialized Cells

Science, Grade 6


Table Of Contents: Specialized Cells

1. Cell Types
The human body consists of trillions of cells, including some 200 different cell types that vary greatly in size, shape and function.
2. Cell Size
Sperm cells are the tiniest human cells, a few micrometers wide (1/12,000th of an inch); whereas the longest cells, the neurons that run from the tip of the big toe to the spinal cord, can be as long as several feet in an average adult!