Difference between Single and Double Circulation.
Answers
Explanation:
A circulatory system in which blood travels only once through the heart in one complete cycle of the body is called single circulation. ... A circulatory system in which blood travels twice through the heart in one complete cycle of the body is called double circulation. it occurs in mammals
The main difference between single circulatory systems and double circulatory systems is that in the case of single circulatory systems, blood passes through the heart only once on each circuit around the whole of the blood circulation system of the animal.
(Conversely, in the case of double circulatory systems, blood passes through the heart twice during one complete circuit around the blood system through the body of the animal.)
Reminder about types of circulation in animals:
The two types of animal circulation systems are:
Open Circulatory Systems
(Circulatory fluid: hemolymph, also called haemolymph)
Closed Circulatory Systems
(Circulatory fluid: blood. Blood is constrained within the heart and blood vessels)
Two types of closed circulation systems are:
Single Circulatory Systems e.g. in fish
Double Circulatory Systems e.g. in mammals
Fish have single circulatory systems in which blood passes through the heart only once each time it completes a full circuit around the fish's body, including through its gills and all other organs and tissues.
More about Single Circulation Systems:
As applies to all closed circulatory systems, single circulation systems consist of blood, blood vessels and a heart.
The fluid (i.e. blood) contained within the network of (blood) vessels must be moved around the system in the correct direction. This is achieved by the heart continuously pumping.
In the case of single circulatory systems, e.g. as in fish, the heart receives deoxygenated blood (also described as 'oxygen-poor blood') into the atrium of the heart and pumps it through the ventricle of the heart so that it continues onwards to the gills.
Note: gills, not lungs, in the case of aquatic animals such as fish.