The Closed circulation Is a system that transports blood through the body of an organism using a system of blood vessels. The heart pumps oxygen-rich blood through the arteries throughout the body and the blood full of debris and deprived of oxygen returns to the heart through the veins.
The circulatory system is one of the transport systems through which nutrients, gases and other molecules are transported within the body of animals. There are two main types of circulatory systems: the open circulatory system and the closed circulatory system.
In the open circulatory system, blood bathes the cells directly in opposition to the closed circulatory system in which the blood travels through the vessels. Since blood in an open circulatory system is not confined to vessels, blood and interstitial fluid have no distinction.
In contrast, blood and interstitial fluid do not mix in a closed circulatory system. A closed circulatory system consists of the heart that pumps blood to the vessels to reach the tissues and organs. Gas exchange in the bloodstream occurs between the smaller vessels (capillaries) and tissues.
In a closed circulatory system, blood passes through different blood vessels to reach different organs. In this set, there is a pulmonary circulation and a systemic circulation. Blood also moves because of a difference in pressure within the blood vessels. This system is ideal for larger animals to supply adequate blood to the extremities.
The closed vascular system is a highly developed system due to:
- The organisms have a thick wall to prevent evaporation of water, so the exchange of materials between the body cells and the environment by diffusion is not possible.
- The organisms have a higher metabolic rate and need a greater supply of nutrients and oxygen. They also need faster disposal of waste and carbon dioxide.
- External temperature changes.
Examples of animals with a closed circulatory system are annelids and vertebrates (including humans). Humans have a cardiovascular system composed of heart and blood vessels that circulate blood throughout the body and another system for the circulation of lymph called the lymphatic system.
Advantages of the closed circulatory system
It is efficient in the delivery of oxygen through an organism
This type of system offers great capacity for the delivery of oxygen. This involves ultrafiltration of the blood, the pulmonary circulation and the systemic circulation. Deoxygenated blood is transported from the heart to the lungs to be oxygenated, which is known as pulmonary circulation.
The oxygenated blood is then transported to the rest of the organs, which is known as systemic circulation. After the blood reaches the tissues through the capillaries, it is returned to the heart through the veins, with blood pressure in the lower venous system compared to that of the arterial system.
Provides more power in the form of pressure
Compared to the open circulatory system, the closed circulatory system works with a much higher blood pressure.
Since oxygen-containing blood can reach the extremities of the body at a much faster rate than with an open circulatory system, humans, as well as other organisms with the closed system, can metabolize much faster, which leads to Faster movements, digestion and waste disposal.
Apart from this, it also allows a better and efficient distribution of antibodies, making immune responses much stronger and making the body more powerful to fight against infections.
It has a lymphatic system that works separately
In this system, the lymphatic system works separately. Blood is responsible for the transport of gases (oxygen and carbon dioxide), cells defend the body by regulating electrolyte and fluid balance, acid and basic balance, and body temperature.
It also protects the body from infection and blood loss through coagulation. Meanwhile, the lymphatic system is responsible for cleaning the cellular environment by providing a pathway to absorb fat and fat-soluble vitamins in the bloodstream.
It also collaborates to return tissue fluids and proteins to the blood and is in charge of the defense of the body against diseases.
Disadvantages of the closed circulatory system
It is more complex than the open circulatory system
Humans, vertebrates, and larger, more active animals have a closed circulatory system. Compared with the open circulatory system, the closed circulatory system is much more complex since it includes two main processes: the pulmonary circulation and the systemic circulation.
While the pulmonary circulation transports deoxygenated blood through the lungs to obtain oxygen, the systemic circulation distributes this oxygenated blood through the body. To direct this blood to all organs and tissues, it uses a network of arteries and veins.
The closed circulatory system works with blood that remains in the vessels and is transported to all extremities of the body at high pressures and fast speed. The open circulatory system is simpler. In this, the heart pumps blood into open cavities, with blood vessels transporting blood under low pressure throughout the body, and then bathes all organs and tissues with blood.
In addition, it does not use the main veins and arteries to raise blood pressure. Organisms with an open circulatory system, such as spiders, insects, mollusks and prawns, usually have a lot of blood, however, they have low blood pressure.
Requires more energy for blood distribution
Compared to the open circulatory system, the closed circulation system requires more energy for blood distribution. That is why it is said that it is designed naturally for animals that have a rapid metabolism and larger bodies.
This is also true considering the fact that oxygenated blood needs a lot of nets to travel to the extremities of the body. A lot of organisms on this planet need a circulatory system in order to distribute the nutrients through your body into an efficient and surviving matter.
It is important to consider that the two types of circulatory systems have their own sets of advantages and disadvantages. Although the closed circulatory system allows a faster distribution and is more advanced, it is not suitable for all species. In reality this system is reduced to where it is most efficient.
References
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