Overleg:Duikreflex

>Veel zoogdieren kennen deze reflex niet. Een kat gaat onder water gewoon door met ademen en verdrinkt.<

Ik geloof er geen woord van. Die kat verdrinkt alleen als je hem lang genoeg onder houdt. de engelse wiki geeft dan ook:

Submerging the face into water causes the mammalian diving reflex, which is found in all mammals (including humans, although it is less pronounced), but especially in marine mammals (as, for example, whales and seals.) This reflex puts the body into oxygen saving mode to maximize the time that can be spent under water, and includes three factors:

   * Bradycardia, a reduction in the heart rate (of about 20% in humans).
   * Peripheral vasoconstriction, a decrease in blood flow to the extremities, in order to increase the supply of blood and oxygen to the vital organs, especially the brain.
   * Blood shift, the shifting of blood plasma to the thoracic cavity, i.e. the chest between the diaphragm and the neck to avoid the collapse of the lungs under higher pressure during deeper dives.

Bart (Evanherk) 28 apr 2007 12:48 (CEST)