(a) The ureters act is urinogenital duct which opens into the cloaca. In females, the ureters and oviduct open separately in the cloaca.
(b) Excretion is performed by un malphigian tubules in cockroaches. Each tubule is lined by glandular and ciliated cells. They absorb nitrogenous waste products and convert them into uric acid which is excreted out through the hindgut.
(c) The body wall of earthworm is covered externally by a thin noncellular cuticle below which is the epidermis, two muscle layers and an innermost coelonic epithelium. The epidermis is made up of a single layer of columnar epithelial cells which contain secretory gland cells.