what does the capillary network in each gill filament provide
Most fish exchange gases using gills on either side of the pharynx (throat). Gills are tissues which consist of cloth and fabric structures called filaments. These filaments have many functions including the transfer of ions and water, as well as the exchange of oxygen, carbon dioxide, acids and ammonia.Each filament contains a capillary network that provides a large surface area for exchanging oxygen and carbon dioxide.he gills push the oxygen-poor water out through openings in the sides of the pharynx. Some fish, like sharks and lampreys, possess multiple gill openings. However, bony fish have a single gill opening on each side. This opening is hidden beneath a protective bony cover called an operculum.