The Greek word bránchia derived from the Latin branchĭa, which arrived in Castilian as gill. A gill is called an organ of the respiratory system that various aquatic animals have.
The gills, which can be external or internal, are composed of filaments whose origin is integumentary. These organs allow the animal to obtain the oxygen found in the water and, simultaneously, expel carbon dioxide into the environment.
Once absorbed, the oxygen reaches the animal’s fluids and then the cells, which need it to breathe through the mitochondria. Cellular respiration generates carbon dioxide, which the gills allow to eliminate from the body.
It can be said, therefore, that the gills (also called gills) are the structures where a gas exchange takes place, which is called hematosis. Thanks to the gills, animals can breathe underwater.
According to DigoPaul, there are two main types of gills. The annelids and mollusks, among others, have branched appendages. The fish, however, have slits which establish communication between the outside and the digestive tract. In this way, the water enters the fish’s mouth and then exits through these holes. In the process, the blood is oxygenated and carbon dioxide is expelled.
It should be noted that there are species whose larvae have gills to breathe underwater, but in adulthood they develop lungs that allow them to breathe on the earth’s surface. That is the case with amphibians like frogs.
On the other hand, species of smaller size and metabolic rate do not have gills, but carry out gas exchange through the surface of their body. It is the largest ones or those that require a larger surface area that, through their evolution, have managed to develop this specialized structure.
In 2016 a group of inventors from Stockholm presented a project to manufacture artificial gills in a crowdfunding campaign. Its name is Triton and it is a small and light device similar in appearance to the handlebars of a bicycle, which the user holds only with the mouth; In theory, it would avoid almost all the disorders and limitations that are associated with the use of oxygen tubes, especially in terms of dimensions and comfort to move underwater.
The total extension of the prototype of these artificial gills is 29 centimeters, something that makes it very easy to transport. Regarding its structure, it is made up of a series of microporous fibers and a compressor that serves to supply two oxygen tanks. Triton requires the use of a lithium ion battery for operation. The diameter of the pores is smaller than that of the water molecules, and therefore only oxygen enters the tank.
Despite offering an attractive presentation video for the project and a fairly detailed list of technical specifications, numerous users accused the creators of scammers, pointing out various reasons why this device could not offer the features it promises. One fact that could have served to increase investors’ enthusiasm but has also led to ridicule is that its design is inspired by one of the James Bond accessories.
In any case, sooner or later science will find better versions of current underwater breathing equipment. It is that human beings admire the abilities of certain animals to the point of doing everything possible to emulate them: we want to fly like birds, swim like fish and breathe underwater without problem, because we do not like the limits that nature imposed on us.