An ECG stands for electrocardiogram. This is a
continuous graph of a patient’s heartbeat. It works by recording the
electrical voltages in the heart. It can help in the monitoring of a
patient as well as in the diagnosis of certain problems with the heart.
An ECG (graph) is plotted by measuring voltages between various points
of the body. Twelve leads in total are connected to various parts of the
body. A print out of a section of the graph is often done. The trace on
the screen, similar to that of an oscilloscope can provide valuable
information to medical staff when monitoring patients. A graph of two
successive heartbeats are displayed below.
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Electron Microscope
The electron microscope offers much
greater magnification than a normal light microscope. It uses electrons
to create an image of the object.
The electron beam originates from a cathode, is accelerated by a voltage
and focussed by magnetic fields. The variation in number of electrons
that penetrate through a thin specimen being examined, results in an
image of the specimen being formed on a computer screen.
The electron microscope is an important tool in many research laboratories. It is often used to examine tiny living things such as microorganisms and cells.
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| Electron Microscope |
