What is Coelom

The coelom is the mesodermally walled chamber between the stomach and the outer body wall. During the gastrulation stage of embryo development, coelom production begins. The archenteron is a blind pouch generated by the developing digestive system of an embryo. Schizocoely is a process that occurs in Protostomes that results in the formation of the coelom.

Development of Coelom

 The archenteron develops initially, followed by the mesoderm, which divides into two layers: the parietal layer, which attaches to the body wall or ectoderm, and the visceral layer, which surrounds the endoderm or alimentary canal. The coelom, also known as the body cavity, is the space between the parietal and visceral layers.In Deuterostomes, enterocoely creates the coelom.

Types of Coelom

Mesodermal diverticula occur on the archenteron wall and hollow out to generate coelomic chambers. Deuterostomes are known as enterocoelomates. Deuterostome coelomates include vertebrates, tunicates, and lancelets, echinoderms (starfish, sea urchins, and sea cucumbers), and hemichordates (starfish, sea urchins, and sea cucumbers) (acorn worms and graptolites). The coelom fulfils several functions. One of the most important duties is to absorb shock and protect the internal organs of the body. In this post, we’ll learn more about coelom, its different varieties, and its various roles. The coelom is a fluid-filled biological chamber located between the intestinal system and the body wall. It is the main body cavity in several animals. True coeloms are bordered with mesodermal cells and are made up of them.

During embryonic development, the coelom is formed by the three germinal layers. Animals are classified according to whether or not they have coelom. Animals with a true coelom are referred to as coelomates, whereas those without one are referred to as acoelomates. Pseudocoelomates are creatures that have a false coelom Acoelomate.

In acoelomates, the coelom is completely absent. In such animals, the blastocoel is completely occupied by the mesoderm. There are just spongocoel and coelenteron present.

Coelomates include Porifera, Coelenterata, Ctenophora, and Platyhelminthes (also known as flatworms).

Pseudocoelomate

Pseudocoelomates are animals that lack a true coelom. As the title implies, the coelom present is a forgery. Such animals have a blastocoel that is partially filled with mesodermal cells. The mesoderm only lines the body cavity in the direction of the body wall and is completely absent in the direction of the gut. An example of a pseudocoelomate is Aschelminthes (roundworms).

Coelomates are animals that have a true coelom. A true coelom derives from the mesoderm and is lined on both sides by mesoderm, which leads to the body wall and gut. In such animals, the blastocoel, which is present in the gastrula, is completely replaced by the true coelom. Mesenteries are the structures that hold the bodily organs in place within the coelom.

Coelomates include Annelida, Arthropoda, Mollusca, Echinodermata, Hemichordate, and Chordata.s

Example of Coelomate

Based on their embryonic development, coelomates are classified as protostomes or deuterostomes. Each of them forms a coelom in a unique way.

The coelom is classified into two types based on how it develops: schizocoelom and enterocoelom.

1. Schizocoelom

Schizocoelom can be discovered in protostomes. The creation of the body cavity, or coelom, originates from the splitting of the mesoderm. One component surrounds the endoderm, while the other surrounds the ectoderm. The region between these two is known as the coelom, and the mouth is known as the blastopore.

Animals with schizocoelous include Annelida, Mollusca, and Arthropoda. Because it is filled with blood, the coelom is known as the hemocoel in Mollusca and Arthropoda.

2. Enterocoelom

Enterocoelom is seen in deuterostomes. The coelom is formed by merging the archenteron’s interior outgrowths. It unites to form a coelom lined by mesoderm. Enterocoelom is found in organisms such as chordates and echinoderms.

Conclusion

Coelom functions as a shock absorber, shielding the body from mechanical shock. It acts as a cushion for internal organs, protecting them from minor bends while still allowing them to be flexible. The coelomic fluid helps soft-bodied animals move and maintain a defined body structure. It functions as the hydrostatic skeleton of the body. Therefore, coelomocyte cells are either attached to or float freely within the coelom wall. They aid the immune system by triggering humoral immunological responses and phagocytosis. The coelomic fluid also aids in gaseous movement and the delivery of nutrients and waste. Organs have enough space to grow and function in Coelom.