Differentiate the tubular structure found in invertebrates

The tubular structure found in invertebrates are:

• Nephridia are the tubular excretor structures of earthworms and other annelids. Nephridia help to remove nitrogenous wastes and maintain a fluid and ionic balance.

• Protonephridia or flame cells are the excretory structures in Platyhelminthes (Flatworms, e.g., Planaria), rotifers, some annelids and the cephalochordate – Amphioxus. Protonephridia are primarily concerned with ionic and fluid volume regulation, i.e., osmoregulation.

• Malpighian tubules are the excretory structures of most of the insects including

cockroaches. Malpighian tubules help in the removal of nitrogenous wastes and osmoregulation.

• Antennal glands or green glands perform the excretory function in

crustaceans like prawns.