Cockroach can live without it’s head for at-least a week. This is because, cockroach breathe through spiracles and the holes present in their body segments, not with lungs or respiratory system like human and this is one of the amazing facts about animals.
They can also survive for more-than a week, if they are given food by some other means.
They use their head to look around things through eyes and drink through mouth. Otherwise, the open circulatory system in their body breathe well and good.
When cockroach head is cut-off, their neck would get sealed and clot, thus preventing from bleeding.
Cockroach brain doesn’t control breathing and so, blood is not circulated throughout the body to carry out oxygen.
The open circulatory system has very less pressure in and do not possess huge network of blood vessels to lose blood like humans.
Their antennae tends to wave for several hours after being removed from body.
Cockroaches are cold-blooded, hence they require very less food intake.
With the help of Trachea(set of tubes present in spiracles), air is passed directly to the cells and tissues of the body.
Cockroach can also survive for a week, with the food they had just for one day.