Blastomere

Blastomere

Precursor	Zygote

A blastomere is a type of cell derived from the division of the zygote after fertilization. Blastomeres are formed during the cleavage stage of embryogenesis, which is the early phase in the development of most eukaryotic organisms. The process of cleavage leads to the formation of a morula, a solid ball of cells, which subsequently transforms into a blastocyst before implantation into the uterus.

Structure and Development

Blastomeres are initially identical cells that make up the embryo. They are undifferentiated and have the potential to develop into any cell type. During the first few divisions of a fertilized egg, the total volume of the embryo does not increase; instead, the zygote divides to produce smaller cells. The pattern and orientation of blastomere divisions can vary significantly between different species.

Function

The primary function of blastomeres is to contribute to the formation of the embryo. Each blastomere has the potential to develop into a complete organism in species where twinning or cloning naturally occurs. In the context of developmental biology, studying how blastomeres differentiate and contribute to the organism's body plan is crucial for understanding early developmental processes.

Clinical Relevance

In assisted reproductive technology (ART), the appearance and quality of blastomeres are important indicators of embryo health and viability. Techniques such as preimplantation genetic diagnosis (PGD) involve the removal of one or more blastomeres from an early-stage embryo to test for specific genetic conditions before transferring the embryo to the uterus.

See Also

• Embryology
• Cell division
• Genetic testing