Which term describes the stage defined by a fluid-filled cavity called a blastocele, an inner cell mass, and an outer trophectoderm?

Which term describes the stage defined by a fluid-filled cavity called a blastocele, an inner cell mass, and an outer trophectoderm?

• A. Blastocyst
• B. Birth (single)
• C. Bleeding after oocyte aspiration
• D. Biochemical pregnancy

Answer: (A)

This is about the embryo stage that has a fluid-filled cavity called the blastocele (also known as the blastocoel), an inner cell mass, and an outer layer called the trophectoderm. Together these features define the blastocyst. The inner cell mass will develop into the fetus, while the trophectoderm will contribute to the placenta. This stage occurs after several rounds of division, as the embryo prepares to implant into the uterine lining. The other terms refer to pregnancy outcomes or events unrelated to this embryonic structure, not to this developmental stage.

This is about the embryo stage that has a fluid-filled cavity called the blastocele (also known as the blastocoel), an inner cell mass, and an outer layer called the trophectoderm. Together these features define the blastocyst. The inner cell mass will develop into the fetus, while the trophectoderm will contribute to the placenta. This stage occurs after several rounds of division, as the embryo prepares to implant into the uterine lining. The other terms refer to pregnancy outcomes or events unrelated to this embryonic structure, not to this developmental stage.