Page 72 - The Miracle in the Mosquito
P. 72

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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