why are gills in fish highly vascularised?
158830
The concentration of oxygen in water is lower than air and it diffuses more slowly. ... Rather than using lungs "Gaseous exchange takes place across the surface of highly vascularised gills over which a one-way current of water is kept flowing by a specialised pumping mechanism.
1463878
Gills. Gills and lungs are the two structures commonly used by animals for respiration. Both are characterized by large amounts of surface area that function in gas exchange. The difference between them is that gills involve external extensions from the body surface, whereas lungs possess internal foldings.
552056
Locate the gills, which are featherlike structures found underneath the carapace and attached to the chelipeds and walking legs. A constant flow of blood to the gills releases carbon dioxide and picks up oxygen. The feathery nature of the gills gives them a very large surface area.
1146199
Gills are very efficient at removing oxygen from water: there is only 1/20 the amount of oxygen present in water as in the same volume of air. Water flows over gills in one direction while blood flows in the opposite direction through gill capillaries. This countercurrent flow maximizes oxygen transfer.
1449429
Fish have what is often described as a two-chambered heart, consisting of one atrium to receive blood and one ventricle to pump it, in contrast to three chambers (two atria, one ventricle) of amphibian and most reptile hearts and four chambers (two atria, two ventricles) of mammal and bird hearts.
1373413
The water enters the mouth and passes through the feathery filaments in the fish's gills, which are rich in blood. These gill filaments absorb oxygen from the water and move it into the bloodstream. ... At the same time, waste carbon dioxide in the blood passes out through the gills back into the water.
1449071
Their blood is transparent.” Detrich said they likely evolved this trait because they live in the cold, stormy waters around Antarctica; the very cold Southern Ocean dissolves much more oxygen than tropical waters. The icefish obtain oxygen in physical solution through their gills and directly through their skin.
749588
Within freshwater fish, the kidney is responsible for preventing excess solute loss as they contain more salts within their blood than the water located around their bodies. ... This is because the fluids inside their bodies are less concentrated than the saltwater around their bodies.
999471
Gills are branching organs located on the side of fish heads that have many, many small blood vessels called capillaries. As the fish opens its mouth, water runs over the gills, and blood in the capillaries picks up oxygen that's dissolved in the water.
390722
But that's because it's perfectly adapted to life in the abyss. So called because of the fluffy appearance of its gills, the frilled shark has six gill slits on either side of the head. It's thought to hunt along the seabed using its senses to find its prey, and when it does it lunges at it like a snake.
588420
Although they have a similar book-like structure, book gills are external, while book lungs are internal. Book gills are still present in the marine arthropod Limulus (horseshoe crabs) which have five pairs of them, the flap in front of them being the genital operculum which lacks gills.
435202
In mammals (like us) there is a double circulation. The right side of the heart receives blood returning back from the body; this blood is low in oxygen (blue in the figure to the right). ... In fish, the heart only has one atrium and one ventricle.
142145
Bettas and Gouramis. These fish belong to the Anabantid family and share the common trait that they can breath oxygen out of the air. They do this through a special organ called the Labyrinth Organ which is a modified gill which sits in a cavity above the gills.
330083
Most fish have some type of structure or structures that are used to pump water over their gills in order to obtain oxygen. However, Albacore tuna have lost these structures and also do not possess a swim bladder.
838713
Many traits of one type of animal appear in the embryo of another type of animal. For example, fish embryos and human embryos both have gill slits. In fish they develop into gills, but in humans they disappear before birth.
1160877
Eels are a specific type of elongated fish, and can be found in both marine and freshwater environments. ... Eels have gills, as most other fish do, and filter air from the water in order to breathe. This means that they never have to go to the surface. Snakes, on the other hand, do not have gills, but lungs.
970011
The main difference between gills and lungs is that gills are the type of respiratory organs specialized to breathe in water, whereas lungs are the type of respiratory organs specialized to breathe in the air. Furthermore, fish use gills while mostly tetrapods use lungs.