He Open and closed circulatory system Are two different ways that living beings have to transport blood through their bodies.
Most large vertebrates, including humans, have a Circulatory system closed . The open circulatory system is found in most invertebrates such as crustaceans, spiders and insects.
It is one of several forms that exist to classify the circulatory system. The main classifications are:
- Single or double circulation; Depends on the number of times the blood passes through the heart.
- Circulation complete or incomplete; Whether oxygenated blood is mixed with non-oxygenated blood.
- C Closed or open circulation; Whether the blood is contained in blood vessels or not.
The circulatory system is composed of the cardiovascular system and the lymphatic system. The cardiovascular system is composed of the heart, blood vessels and blood.
The lymphatic system consists of vessels and lymphatic organs (the spleen and thymus), bone marrow, lymph nodes, lymph The lymphatic fluid.
Closed circulatory system
In this system the blood travels through the blood vessels and does not leave them, making a complete journey that leaves the heart and reaches the heart.
In addition to vertebrates, this type of system also has some higher invertebrates such as annelids (worms, caterpillars, worms and leeches) and cephalopods (squids, octopuses, cuttlefish and seahorses).
Blood circulates through arteries, veins and capillaries like motorways and streets that carry nutrients and oxygen and returns with the waste materials produced by the body after all its multiple interactions.
Blood flow travels in two different circuits; The first of them is performed on the right side of the heart and is the one that carries deoxygenated blood to the lungs. It is the so-called pulmonary circulation.
The other circuit is the left side of the heart and is the one that carries the oxygenated blood through the lungs, to all the organs of the body and returns it back to the heart. It is the so-called systemic circulation.
The blood is pumped by the powerful muscle of the heart and keeps circulating through veins and arteries thanks to the high pressure that causes the pump. In this way, it reaches every hidden place in the body.
The heart of the human being is a very complex organ that has 4 cavities (two atria and two ventricles) within which the blood enters and leaves constantly.
Being a closed system, the blood does not make direct contact with the organs, that is, the blood never exits the"channels"that contain it.
Open circulatory system
It is also known as the lagoon circulatory system. In this system blood is not necessarily always within the blood vessels; Leaves the heart and is going to irrigate directly to the organs and then return by other ways or mechanisms.
To be understood more easily, we must think of this system acting on organisms that are much smaller and less complex than mammals or any other large vertebrate.
Invertebrate animals are usually much smaller, so their blood does not need as much pressure to travel the body and travel more slowly aided, in part, by the muscle movement of the animal.
In this type of organisms, in addition to a slow circulation, breathing, metabolism, digestion and locomotion are also slow.
Among the animals that have this type of system are crustaceans, spiders and insects, as well as snails and clams.
These animals may have one or more hearts, but in many cases there is not even a heart as such.
Blood vessels are not such as blood"bathes"the organs through open breasts, and even the blood of these organisms can not be called blood, since it is combined with interstitial fluid. This fluid is called"hemolymph"which provides nutrients and oxygen to organs and cells.
In the case of crustaceans, for example, the circulatory system is similar to that of arthropods; The number and complexity of the capillaries depends directly on the size of the animal and the arteries can function as reservoirs of pressure to irrigate the blood.
In these animals the heart is usually elongated and tubular, but in some cases it does not exist, nor can arteries properly exist.
Sometimes there is a heart without arteries, especially in smaller crustaceans. If the animals are larger, there may be an accessory pump.
Insects mostly have a dorsal aorta as the only blood vessel that crosses most of their body.
The heart has small holes called ostiolos through which the hemolymph enters and leaves when it contracts peristaltically to push it towards the rest of the body.
In some cases, there may be lateral arteries that form from the dorsal vessel. In any case, the blood vessel (s) terminate abruptly and almost without branching, sending the blood directly.
In insects, the circulatory system carries more nutrients than oxygen; The latter arrives in greater quantity through the respiratory system of the animal.
References
- Hill, Wyse and Anderson (2004). Animal Physiology. Pan American Medical Publishing House. P. 758.
- The crustaceans. Recovered from cccurstaceos.blogspot.com.ar.
- Animal circulatory system. Recovered from monografías.com.
- Circulatory apparatus of animals. Types of systems, examples. Retrieved from paradis-sphynx.com.
- Closed and open circulatory system. Circulatory System Martinez. Retrieved from sites.google.com.
- Open or closed circulatory system. Recovered from lasaludi.info.