What is the Difference Between Single and Double Circulation?

Single and double circulation are types of closed circulatory systems, where blood flows throughout the body in closed blood vessels, such as arteries and veins. The main differences between single and double circulation are:

1. Pathway: In single circulation, blood flows to and from the heart through a single pathway, while in double circulation, there are two separate pathways connected to the heart through which oxygenated and deoxygenated blood flows.
2. Number of circulations: In single circulation, blood flows through the heart only once to complete the circuit, whereas in double circulation, blood flows through the heart twice to complete the full circuit.
3. Efficiency: Double circulation is more efficient than single circulation because the blood flows at a higher pressure, which increases the rate of oxygen and nutrient delivery to the body's tissues. In single circulation, the oxygenated blood flows at a low pressure, decreasing the efficiency of circulation.
4. Animals: Single circulation is found only in fishes, while double circulation is found in amphibians, reptiles, birds, and mammals.

In summary, single circulation is a less efficient system where blood flows through the heart only once and is found only in fishes. In contrast, double circulation is a more efficient system where blood flows through the heart twice and is found in amphibians, reptiles, birds, and mammals.

Comparative Table: Single vs Double Circulation

Single and double circulation are two types of closed circulatory systems, where blood flows through sealed vessels, such as arteries and veins. The main differences between single and double circulation are summarized in the following table:

In single circulation, blood flows through a single pathway to and from the heart, and it is less efficient than double circulation. This type of circulation is found in fish and some amphibians. In double circulation, blood flows in two separate pathways, pulmonary circulation and systemic circulation, and it is more efficient than single circulation. This type of circulation is found in mammals, birds, and reptiles. The oxygenated and deoxygenated blood is not mixed in the heart in double circulation.