Genetic testing of an embryo is available to couples who want to avoid passing on a genetic defect to their offspring.One method of testing involves removing a single blastomere from an 8-cell stage embryo and analyzing it to determine if it carries the mutant gene.If no mutation is found,the now 7-cell embryo can be implanted in the woman,and it can go on to develop into a healthy infant.These results indicate that
A) at least one of the cells in the human embryo at the 8-cell stage is not used in development.
B) the embryo can compensate for the loss of a cell.
C) not all cells are equally important.
D) the human embryo at the 8-cell stage has not yet formed an inner-cell mass.
E) the cell that is removed for testing is derived from the trophoblast.

Question

Quizplus · Accepted Answer

The fact that an 8-cell embryo can develop normally after having one cell removed suggests that the remaining cells can compensate for the loss of one cell. This indicates that the cells are not equally important and that the embryo has some degree of plasticity or robustness in its development.

Genetic Testing of an Embryo Is Available to Couples Who