Paramecium (P. caudatum)
0.225 mm
Cell length
A slipper-shaped single cell that swims with thousands of tiny hairs. 0.12 to 0.33 mm long.
Published
How big is that?
0.225 mm is 3.2 times the width of a human hair and 3.1% of a grain of rice.
Paramecium is the 11th smallest of the 32 Tiny Worlds objects, and the 11th smallest of the 172 objects across all five SizeItUp games.
Size comparison
To scale, smallest to largest: Paramecium in orange beside the Tiny Worlds objects nearest in size, in teal.
| Object | Size | vs Paramecium |
|---|---|---|
| Human hair (Width)A strand of scalp hair, measured across. | 70 µm across | 31% of the size |
| Human egg cellThe largest cell in the human body, at ovulation. | 0.115 mm across | 51% of the size |
| Paramecium (P. caudatum) | 0.225 mm long | – |
| Tardigrade (Water bear)A chubby eight-legged micro-animal that can survive drying out, seen from the side. | 0.25 mm long | 1.1× bigger |
| Grain of sand (Medium)A grain of medium sand, as geologists grade it. | 0.375 mm across | 1.7× bigger |
In other units
| Micrometres | 225 |
|---|---|
| Millimetres | 0.225 |
| Centimetres | 0.0225 |
| Metres | 0.000225 |
How it's measured
Cell length. Midpoint of 0.12 to 0.33 mm (ARTIS Micropia, Amsterdam).
The source gives a range, so this is the middle of it.
Sources
- artis.nl: ARTIS Micropia, Paramecium caudatum: size 0.12-0.33 mm.
Checked against the source on .
Could you have guessed it by eye?
Paramecium is one of the objects in Tiny Worlds, a daily size comparison game: you stretch a shape to the size you think is right beside one you know.