PHYSICS

The magnetotactic bacteria (i.e., Magnetospirillum gryphiswaldense,
Magnetobacterium bavaricum) move "north-seekingly",
following the magnetic lines northward (such a movement along
the magnetic field lines is called magnetotaxis). The magnetic
response is caused by small particles of magnetite, Fe30 4' arranged
in chains. Their magnetic moment rotates these bacteria, alive as
well as dead, into position parallel to the field lines with the
front end toward the north.
The magnetic orientation in animals is characterized by a
complex relationshi p between stimulus and response. This orientation
behavior of animals includes compass orientation, response
to magnetic gradients, to temporal variations and so on.
Some insects demonstrate a tendency to align their body axis
with the cardinal axes of the magnetic field, i.e., the termite
queens of Odontotermes sp. and Termes malabaricus, the cockchafer
Melolontha melolontha, resting long-horned beetles Hylotrupes
bajulus, cockroach Blatta americana, the cricket Acheta domestica,
and yellow jackets Paravespula sp. In honeybees, Apis
melifera, alignment responses have been described in connection
with preferred resting positions and in connection with the waggle
dance by which bees inform their nestmates about the position of
food sources.
Salamander Eurycea lucifuga, frogs, use the magnetic field for
orientation when they have to find the direction of the nearest
shore quickly, e.g., when they sense danger.
Among vertebrates, fish such as goldfish Carassius auratus,
European Eels Anguilla anguilla, Rainbow Trout Oncorhynchus
mykiss, are the only group for which alignment behaviors have
been reported.
The birds monitor the Earth's magnetic field during migration,
apparently with their visual system and with tiny grains of
magnetite in their heads.
20.2. MAGNETOTHERAPY
Magnetotherapy is a way of treatment of disease by the
application of magnets to the surface of the body.
There are numerous references which inform about the magnetic
therapy as a method of healing (f.e., cancer) using external
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magnets to help heal the body. But the Food and Drug Administration
has not evaluated any of these statements. The information
contained in these references is not intended to diagnose,
treat, cure or prevent any disease. This information is not meant
to replace any doctor and patient consultation.
VOCABULARY
Enzlish Ukrainian Enalish Ukrainian
Bar magnet Crpaxneno­ Magnetocardiozraphzriorpadiis
Marniroxap­
.D:i6HHH MarHiT
Electromagnetic
flow meter HiTHHH BHMi- phalography