yksikammioiset

Yksikammioiset refers to a type of heart structure found in some animals, particularly in fish and amphibians during their larval stages. In a single-chambered heart, there is only one atrium and one ventricle. Blood enters the atrium from the body, then passes into the ventricle. The ventricle then pumps this deoxygenated blood to the gills for oxygenation, after which it circulates through the rest of the body. This contrasts with the more complex two-chambered hearts found in adult fish, or the even more complex four-chambered hearts found in birds and mammals. The simple, single-chambered design is efficient for organisms with lower metabolic demands, such as those that respire through gills and have a less active lifestyle. As many amphibians develop, their circulatory system transitions to a more advanced structure, typically a three-chambered heart with two atria and one ventricle, allowing for a more efficient separation of oxygenated and deoxygenated blood.