BLASTODERMA Meaning and
Definition
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Blastoderma refers to the early embryonic stage in certain organisms, particularly in birds and reptiles, where a single layer of cells forms an outer membrane surrounding the yolk. This membrane is responsible for protecting and nourishing the developing embryo.
In birds, the blastoderma is a crucial structure that forms after fertilization of the egg. It is composed of several cells known as blastodermic cells, which divide and differentiate into various specialized tissues and organs as the embryo develops. The blastoderma is responsible for the formation of the epiblast and the hypoblast, two distinct layers that give rise to the different cell types and tissues in the embryo.
In reptiles, the blastoderma, also known as the blastodisc, functions similarly. It is a disc-shaped structure that covers the yolk and initiates the development of the embryo. The blastoderma in reptiles contains cells that differentiate into the ectoderm, endoderm, and mesoderm, which are the three germ layers responsible for the formation of all the tissues and organs in the organism.
Overall, blastoderma is a critically important structure in avian and reptilian embryogenesis, playing a fundamental role in the development of these organisms.
Etymology of BLASTODERMA
The word blastoderma has its origin in the Greek language. It is formed by combining two Greek roots: blastos meaning germ or bud, and derma meaning skin or layer. Therefore, the etymology of blastoderma can be understood as germ layer or embryonic skin.
