Page 72 - The Miracle in the Mosquito
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THE MIRACLE IN THE MOSQUITO
The mosquito sucks the blood by sticking the tube into the
hole it has opened in the skin. Thanks to this tube it can penetrate
a small vein and drink blood directly. Or it can drink the blood
that accumulates in the surrounding tissue when the skin is cut.
Usually the piercing needles go into the skin vertically. The
most important characteristic of the mosquito’s needle is that it
can bend at a certain depth. Thanks to this remarkable feature, the
needle can easily move around under the skin, even to the point of
being able to extend parallel to the skin. In this way the needle is
able to get to the places where there is the highest concentration of
veins.
However, here a serious problem awaits the mosquito. As
soon as a mosquito bites, a kind of defence system goes into oper-
ation in the human body. An enzyme that prevents microbes from
entering the body and stops the bleeding is secreted in the region
of the wound. This enzyme enables the blood to clot. Once the
blood starts clotting it is impossible for the mosquito to drink any
blood. (Coagulation is caused by the transformation of fibrinogen,
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