Human embryos gain biological identity from 14th day after fertilization
Q. There is a 14 day rule to restrict research on human embryos. The 14th day is important because- Published on 10 May 16a. By then the embryo shows signs of biological identity
b. It attaches to the mother’s womb on the 14th day
c. Differentiation starts on the 14th day
d. All of the above
ANSWER: By then the embryo shows signs of biological identity
- The fourteenth day is an important day in the development of the embryo because it is when the “primitive streak,” a faint band of cells marking the head-to-tail axis, is formed.
- The primitive streak is the first indication that the embryo has developed a biological identity, because, before this stage, the embryos can divide in two.
- This has therefore been chosen as the point to draw the line for human embryo research.
- Being able to clinically observe the blastocyte beyond seven days is important because this is the time when the blastocyte normally attaches itself to the mother’s womb in a process termed implantation. It is not exactly on the 14th day.
