Neuroscience for Kids - Electron Microscopy

The Synapse- Up Close and Personal

Developed in the 1950's, the electronmicroscopecan magnify objects thousands of times. The electron microscopepasses electrons through an object and the resulting image is recorded onfilm.

Using the electron microscope, Dr. PatiIrish in the Department ofNeurological Surgery at the University of Washington has taken thesepictures of synapses. The "d" represents adendrite and the "R" represents an axon terminal. If you look closely,you can even see some round synaptic vesicles that containneurotransmitters. The fuzzy black areas represent the actual synapsebetween terminal and dendrite. The larger oval objects (there are two inthe dendrite of image 1 and one in the dendrite of image 2 are"mitochondria".
Image 1 Image 2

This page is Java enhanced.
You will need a Java-capable browser to view itsapplet
This page is Java enhanced.
You will need a Java-capable browser to view itsapplet
The applet code for the magnification ofthese photos was written by Dr. Paul Kenyon in theDepartment of Psychology, University of Plymouth, Devon,UK

Photographs using the electron microscope have shownthat synapses can be either asymmetrical (redarrow) or symmetrical (green arrow). Inthe figure on the left, notice that the red arrow is pointing to a synapsethat has one dark band and one lighter band. The green arrow is pointingto a synapse that has two dark bands. Asymmetrical synapses are thoughtto be excitatory synapses and symmetrical synapse are thought to beinhibitory synapses. The yellowline outlines the dendrite (D).

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Synapses

Exploring theNervous System