Medicine:Cavitation (embryology)

An open cavitation.

Cavitation is the formation of cavities, which are spaces or openings in the body. This process occurs in mammalian embryos, and can also occur later on in fully developed organisms. During mammalian embryo development, cavitation is a routine process; however, the formation of cavities in fully developed organs, especially in lung tissue, is usually the sign of a severe medical condition or disease, such as tuberculosis.

Developmental

After the process of cavitation occurs the blastocoel forms. Following the formation of the blastocoel, the inner cell mass positions itself in one portion of the inner cavity, while the rest of the cavity is filled with fluid.

Cavitation is a crucial process in the development of mammalian embryos. After fertilization, rapid cell division occurs which results in the formation of the morula, or a solid ball of cells. The morula is the precursor structure to the blastula, which is an animal embryo in the early stages of development. The morula consists of a cluster of internal cells covered by a layer of external cells. The internal cells become the inner cellular mass, which becomes the entire embryo. The external cells are destined to become a structure called the trophoblast, a layer of tissue on the inside of the embryo that provides it with nourishment. The trophoblast cells become extraembryonic structures necessary for development. After the initial formation of the morula, it does not have an interior space or cavity. Cavitation occurs to create a cavity on the inside of the morula. This process occurs when trophoblast cells, in other words the outside covering of the blastocyst, secretes fluid into the morula creating the blastocoel, the fluid filled cavity of the blastula. The formation of the blastocoel is a critical stage in the formation of the blastocyst, which is a blastula where some cellular differentiation has already occurred.