Do you know that all small insects have nervous system?

Do you know that all small insects have nervous system 

Do you know that all small insects have nervous system status of the brain that receive sensations and send some commands to the muscles to do a particular job. For the blood of insects is not red like human blood because it contains no oxygen and therefore does not contain red cells.

The heart of the insect part of a long tube extending in the upper part of the body directly under the skin and open directly under the brain. And this permeates the tube absorbs the small holes through the heart and pump blood to the head. A focus on the blood brain then applies a return in the body and wash the way members of the body, muscles and nerves. And thus carries with it remnants of digested food to be expelled to the outside.