Question

Describe the structure and function of the heart in Periplaneta? (K)

Answer 1

The heart of cockroach consists of mid dorsal, elongated, contractile, narrow tube called aorta lying just behind the terga. The heart is present inside the pericardial sinus whose walls are composed of segmented alary muscles and a dorsal diaphragm. The heart has 13 funnel shaped chambers which are arranged segmentally. Each chamber has ostia at the hinder end which allow the flow of blood only in one direction. A pair of excurrent arteries emerge from each segment. The aorta and arteries open in haemocoelic regions.