Question

What happens to the blastocyst immediately after implantation?

Answer 1

Implantation:

1. In humans, the first stage of pregnancy is known as implantation.
2. The process of inserting the zygote into the uterine wall is known as implantation.
3. This happens during the blastocyst stage, around a week after ovulation.

Blastocyst:

1. Following fertilisation, a single-celled entity known as the zygote is created.
2. The zygote goes through a sequence of cell divisions, which results in the creation of a hollow cell mass known as the blastocyst.
3. It is created between 5-14 days after conception by a process known as blastulation.
4. The blastocyst clings to the uterine endometrial wall.

Process during blastocyst:

1. Implantation is the process of attaching a blastocyst to the uterine wall.
2. The blastocyst implants and, together with uterine tissue, forms the decidua, the maternal component of the placenta.
3. Chorionic villi are finger-like extensions on the trophoblast that surround the uterine tissue and maternal blood after implantation.
4. The chorionic villi and uterine tissue interdigitate and form the placenta, a structural and functional unit between the growing embryo and the mother body.
5. An umbilical cord connects the placenta to the embryo, which aids in the movement of chemicals to and from the embryo.
6. The inner cell mass divides into three germ layers: the outer ectoderm, the middle mesoderm, and the inner endoderm.
7. Starting with the primordia, these fundamental germ layers give rise to all tissues and organs.