An early stage in the development of a mammalian embryo, consisting of a hollow ball of cells that will later form the embryo and the placenta.
An early stage in the development of a mammalian embryo, consisting of a hollow ball of cells that will later form the embryo and the placenta. In humans the blastocyst consists of around 70 to 100 cells, and forms about five days after fertilisation. Even at this stage the tissue that will form the embryo has differentiated from tissue that will form the placenta.
In humans the blastocyst consists of around 70 to 100 cells, and forms about five days after fertilisation. Even at this stage the tissue that will form the embryo has differentiated from tissue that will form the placenta.