What are the functions of the heart and kidney in clams?
Sep 1, 2017
Clam is a bivalve mollusc and heart along with kidney forms an organ complex. There is an open blood vascular system in clams.
- Heart has paired auricles but single ventricle. Heart receives and pumps only oxygenated blood (=haemolymph) in clams and other bivalves.
- Heart is enclosed within a pericardial cavity. Paired U-shaped kidneys are connected to pericardial cavity on one end and the opposite ends open in mantle cavity.
- Ultrafiltration of haemolymph takes place in pericardial glands, also called Keber's organs. These are present on the auricular wall of heart. Accumulated waste is deposited in pericardial cavity.
- Liquid waste from pericardial cavity enters kidneys where reabsorption and secretion of nutrients/ions take place. Urine is mainly made of ammonia and water. Kidneys are also able to remove heavy metals from blood.
- Urine is excreted in mantle cavity.