part_of part of extracellular component body region pseudocoelom worm_anatomy WBPaper:00038216 body cavity WBbt:0005745 A fluid-filled space enclosed on the outside by the basal laminae of the bodywall tissues, principally those of the bodywall muscles and the hypodermis. Within this space the digestive tract and reproductive tract lie separately, each enclosed by its own basal lamina. Intercellular signals, nutrients and waste products can travel between all tissues bordering this space. coelomic system