How Big is a ... ?
The head of a pin is about 2mm in diameter. Use this animation to compare the relative sizes of cells and organisms sitting on a pinhead. Nearly invisible without magnification, dust mites dwarf pollen grains and human cells. In turn, bacteria and viruses are even smaller.
Download this animation and its matching PowerPoint® ($).
How to use:
- Use the left and right arrows to change magnification.
- Click on the magnifications (1, 10, 100...) for a "Power of Ten" zoom.
- Choose an individual cell or organism (right) to bring it into view.
- Use the scale to measure individual cells.
1 millimeter = 0.001 meter
1 micron = 0.000001 meter
1 nanometer = 0.000000001 meter
metric system, micron, angstrom, virus, bacteria, nanotechnology