Cell body diameter20 millionths m
333 millionthsStacked hamsters
37.7 millionthsUkulele lengths
7.3 billionthsGolden Gate Bridges
About 20 micrometers
Photo from Wikimedia Commons
Neuron
The electrically excitable cell that makes thought possible/Biology & Ecosystems
A neuron is a specialized cell that transmits information through electrical and chemical signals. The human brain contains roughly 86 billion neurons. A typical motor neuron has a cell body about 20 micrometers in diameter, but its axon can stretch over a meter from the spinal cord to muscles in the foot. Signals travel along myelinated axons at speeds up to 120 meters per second. At rest, a neuron maintains a membrane potential of about negative 70 millivolts.
Measurements
Longest axon1 m
41.7 quadrillionthsVoyager 1 distances
10 billionX-ray wavelengths
1.09Tennis nets
Spinal cord to foot
Signal conduction speed120 m/s
1.1 hundredthsEarth escape velocities
11.5Usain Bolts
1.6 hundredthsISS orbital speeds
In myelinated axons
Single neuron mass1 billionths kg
13.9 trillionthsFull beer kegs
11.1 trillionthsHome safes
Neurons in human brain86 billion neurons
3.3 billionAlphabets
86 billionThumbs up
3.1 billionMonopoly properties
Maximum firing rate500 Hz
1,786Eye blinks
8.33Rattlesnake rattles