Cells Alive!

Cells Alive How Big interactive - see size comparisons of a human hair, a dust mite, pollen, bacteria, and viruses

  The Cells Alive!  website is a great resource for biology teachers and home educators covering cell biology. One of the most unique features of this site — which can be used for elementary through college students — is the How Big? interactive.  Zoom in to see the relative sizes of a pin head, a…

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