Difference Between Open and Closed Circulatory Systems (With Table)

In the animal kingdom, various physical characteristics define different phyla. The circulatory system in biology is fundamentally different. The circulatory system is used by complex species to deliver oxygenated blood around their systems. These circulatory systems have a number of traits that set them apart from one another.

Open vs Closed Circulatory Systems

The main difference between Open and Closed Circulatory Systems is that Blood is pumped all through the bodies of human organisms, passing through veins and arteries. This form of loop is known as a closed-loop. Blood circulates freely through the body’s cavities because there are no vessels to contain it, leading to open circulation.

Invertebrates are the most prevalent animals with an open circulatory system. Blood cannot be transported because there are no blood arteries. Therefore it can freely flow in the emptiness. The open circulatory system lacks blood vessels, and organs and tissues are surrounded by hemolymph. This circulatory system is found in insects and snails, for example. The blood cavity is the central bodily cavity present in these animals.

A closed circulatory system emerges invertebrates and a few invertebrates. The system carries blood throughout the body when blood vessels are present. Inside the closed circulatory system, there are two types of blood vessels: arteries and veins. Blood travels through these closed blood arteries rather than through an open circulatory system, bringing vitamins, oxygen, hormones, and other substances to tissues throughout the body. A human being’s circulatory system is closed.

Comparison Table Between Open and Closed Circulatory Systems

Parameters of Comparison

Open Circulatory System

Closed Circulatory System

Open/Closed Spaces

Lacunae and sinuses are open areas in which the hemolymph bathes all of the organs in the body.

Blood circulates through arteries and veins, which are closed blood vessels.

Type of Fluid

Hemolymph. 

Blood. 

Flow Rate

Slow. 

Rapid. 

Blood Vessels

There is a dorsal blood vessel.

There are blood arteries in both the dorsal and ventral hemispheres.

Capillary System

There is no capillary system.

The capillary system is present. 

What is Open Circulatory System?

In the open circulatory system, blood passes through cavities and sinuses. The circulating liquid is Hemolymph, while the open cavity is Hemocoel. Because there are no closed blood vessels, the organs are completely submerged in the hemolymph. This circulatory system is seen in arthropods and mollusks. In the open circulatory system, blood is pumped directly into the body cavity. Because there are no capillaries, only the dorsal blood vessels can be seen.

Because the hemolymph is in close proximity to the tissues, nutrients are directly exchanged between the fluid and the tissue. An open circulatory system’s fluid flow rate is slower than that of a closed circulatory system. Furthermore, no respiratory pigments are present, and blood volume cannot be altered. An open circulatory system is less efficient when compared to a closed circulatory system. The open circulatory system of mammals does not allow blood to travel via the blood vessels.

Insects’ circulatory systems are open because they lack valves, capillaries, and arteries to transfer blood. The blood covers all human tissues and organs in an open circulatory system. Because blood is carried directly to all parts of the body without the use of blood arteries, animals using this system have reduced blood pressure.

What is Closed Circulatory System?

The closed circulatory system involves the heart pumping blood through veins to every tissue and organ in the body. This type of circulatory system includes the capillary system as well as dorsal and ventral blood channels. Because blood travels through clogged arteries, these tissues do not come into direct contact with it. The blood stays in the vessels in a closed systemic circulation.

Blood is kept isolated from somatic cells in this procedure. In this design, the heart pumps blood at a steady rate. Blood is pumped at a higher pressure as a result. In species with a closed circulatory system, blood does not really fill body gaps. Many animals, including humans, have a heart, breathing, and lymph vessels. There are a variety of heart designs for species having a closed circulatory system.

Blood is kept isolated from somatic cells in this procedure. In this design, the heart pumps blood at a steady rate. Blood is pumped at a higher pressure as a result. In species with a closed circulatory system, blood does not really fill body gaps. Many animals, including humans, have a heart, breathing, and lymph vessels.

Main Differences Between Open and Closed Circulatory Systems

  1. Lacunae and sinuses are open areas in which the hemolymph bathes all of the organs in the body, whereas Blood circulates through arteries and veins, which are closed blood vessels.
  2. Blood flows in the closed circulatory system, while hemolymph circulates in the open circulatory system.
  3. The fluid in the open circulatory system is moving at a slow pace, whereas The fluid in the closed circulatory system is flowing at a high rate.
  4. The open circulatory system contains the dorsal blood vessel, whereas The closed circulatory system has both dorsal and ventral blood arteries.
  5. The open circulatory system doesn’t consist of the capillary system, whereas the closed circulatory consists of the capillary system.

Conclusion

Despite the fact that open and closed circulatory systems differ in many ways, they all serve the same purpose in terms of nutrient delivery and flow characteristics. Hemolymph is the fluid that circulates in the open circulatory system without closed blood vessels, whereas blood is the fluid that circulates in the closed circulatory system’s arteries and veins.

Any circulatory system in an individual’s body has the primary job of transporting oxygen and nutrients to various organs while also eliminating waste. The lymphatic system is a portion of the circulatory system that moves at a much slower rate than blood.

References

  1. https://www.journals.uchicago.edu/doi/abs/10.1086/physzool.23.2.30152069
  2. https://anatomypubs.onlinelibrary.wiley.com/doi/abs/10.1002/ar.1090650104