Image: Seals are consumers. An ecosystem is made up of animals, plants and bacteria as well as the physical and chemical environment they live in. The living parts of an ecosystem are called factors while the environmental factors that they interact with are called abiotic factors.
Atrial natriuretic peptide (ANP), also called atrial natriuretic factor (ANF), atrial natriuretic hormone (ANH), cardionatrine, cardiodilatin (CDD), or atriopeptin, is a powerful vasodilator, and a protein (polypeptide) hormone secreted by heart muscle cells.
It is released by muscle cells in the upper chambers (atria) of the heart (atrial myocytes) in response to high blood volume. ANP acts to reduce the water, sodium and adipose loads on the circulatory system, thereby reducing blood pressure.