spiral valve
Quick Summary
The term "spiral valve" can refer to two distinct anatomical structures.
In the context of fish anatomy, a spiral valve is a modification of the intestine that increases its surface area for nutrient absorption. This structure is found in the intestines of sharks, rays, lungfish, and some other primitive fish species.1
In human anatomy, the valvula spiralis, also known as the valve of Heister, is a spiral fold of mucous membrane located within the cystic duct, which connects the gallbladder to the common bile duct. Its function is to regulate the flow of bile.23
The term "spirivalve" is an adjective used to describe something that has a spiral shell, typically referring to gastropod mollusks.4
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circulatory systemFishes…spiral pattern and called the spiral valve. The ventral aorta is also subdivided internally. The result is that oxygenated blood from the left side of the ventricle is directed into the ventral division of the ventral aorta and passes to the anterior of the arterial arches, while deoxygenated blood from…
Read More…spiral pattern and called the spiral valve. The ventral aorta is also subdivided internally. The result is that oxygenated blood from the left side of the ventricle is directed into the ventral division of the ventral aorta and passes to the anterior of the arterial arches, while deoxygenated blood from…
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human digestive systemEvolutionary developmentAnother adaptation is the spiral valve of many primitive fishes, including sharks.
Read MoreAnother adaptation is the spiral valve of many primitive fishes, including sharks.
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