User:Xyvi/sandbox

Thermoregulation
Fish are cold-blooded, and in general their body temperature is the same as that of their surroundings. They gain and lose heat through their skin and during respiration and are able to regulate their circulation in response to changes in water temperature by increasing or reducing the blood flow to the gills. Metabolic heat generated in the muscles or gut is quickly dissipated through the gills, with blood being diverted away from the gills during exposure to cold. Because of their relative inability to control their blood temperature, most teleosts can only survive in a small range of water temperatures.

Tuna and other fast-swimming ocean-going fish maintain their muscles at higher temperatures than their environment for efficient locomotion. Tuna achieve muscle temperatures 19 F-change or even higher above the surroundings by having a counterflow system in which the metabolic heat produced by the muscles and present in the venous blood, pre-warms the arterial blood before it reaches the muscles. Other adaptations of tuna for speed include a streamlined, spindle-shaped body, fins designed to reduce drag, and muscles with a raised myoglobin content, which gives these a reddish colour and makes for a more efficient use of oxygen. In polar regions and in the deep ocean, where the temperature is a few degrees above freezing point, some large fish, such as the swordfish, marlin and tuna, have a heating mechanism which raises the temperature of the brain and eye, allowing them significantly better vision than their cold-blooded prey.

Copied from [[Teleost ]]

Teleost (Bony Fish) :

Cold temperature adaptations in membrane fatty acids

Teleost fish species that inhabit colder waters have a higher proportion of unsaturated fatty acids in brain cell membranes compared to fish from warmer waters, which allows them to maintain appropriate membrane fluidity in the environments in which they live (Logue, J.A., et al., 2000). When cold acclimated, teleost fish show physiological changes in skeletal muscle that include increased mitochondrial and capillary density (Johnston and Dunn, 1987). This reduces diffusion distances and aids in the production of aerobic ATP, which helps to compensate for the drop in metabolic rate associated with colder temperatures.

'''I believe that my addition to the Wikipedia page should go underneath the section about the teleost Physiology within or after the thermoregulation headline. The authors speak about how their bodies adapt to cold temperatures, but it does not include the effects that these adaptations have on the teleost species.'''