Which term refers to an individual cell within a cleavage-stage embryo?

Which term refers to an individual cell within a cleavage-stage embryo?

• A. Biochemical pregnancy
• B. Blastocoele
• C. Blastomere
• D. Chimerism

Answer: (C)

During cleavage, the fertilized egg divides into smaller cells without growing in size. Each of those individual cells is called a blastomere. Blastomeres are the building blocks of the early embryo as it progresses from a 2-cell to a 4-cell, 8-cell stage, and so on, before forming the morula and later the blastocyst. This term specifically names the cells produced by cleavage, making it the correct choice. The other terms refer to different concepts: a biochemical pregnancy describes pregnancy detected by hormones rather than cellular terminology; the blastocoele is the fluid-filled cavity inside a blastocyst, not a cell; and chimerism refers to the presence of two genetically distinct cell populations within one individual.

During cleavage, the fertilized egg divides into smaller cells without growing in size. Each of those individual cells is called a blastomere. Blastomeres are the building blocks of the early embryo as it progresses from a 2-cell to a 4-cell, 8-cell stage, and so on, before forming the morula and later the blastocyst. This term specifically names the cells produced by cleavage, making it the correct choice.

The other terms refer to different concepts: a biochemical pregnancy describes pregnancy detected by hormones rather than cellular terminology; the blastocoele is the fluid-filled cavity inside a blastocyst, not a cell; and chimerism refers to the presence of two genetically distinct cell populations within one individual.