A cockroach’s body is divided into three sections: head, thorax and abdomen. Small openings called spiracles are present in their bodies through which the exchange of gases takes place. A network of air tubes is present in their body, known as the tracheal system with the trachea and tracheoles, for gas exchange. During inspiration, oxygen rushes through spiracles to the trachea and then reaches to every cell and tissue of the body. Similarly, carbon dioxide moves through the tracheal tubes and moves out through the spiracles. So, cockroaches do not have lungs but have a solid respiratory system, somewhat similar to humans.