DR. ALBERTINI’SPHOTO GALLERY
In Doctor Albertini’s latest entry into his photo gallery series we dive into what happens to the egg once matured and fertilized.
Figure 1.
Demonstrates an egg shortly after being fertilized by ICSI. Quite often, the egg contracts away from the zona pellucida, a sign that forces are being generated in the cytoplasm that will rearrange the various organelles so that they are equally distributed each time the embryo divides by mitosis.
Figure 2.
Shows a 4-cell human embryo where the blastomeres have separated into equal sized cells that will eventually follow a path to becoming the inner cell mass and embryo proper OR will become positioned towards the outside of the embryo and will pursue a line of development leading to the placenta-the so-called trophectoderm. Note this image is taken from Carnegie Collection and represents likely the first ever human embryo seen and studied at this stage of development.
Figure 3. With the latest technologies available to scientists at the Center for Human Reproduction (CHR) and elsewhere, human embryos can be explored at very high magnification and in an intact state. Here is a gallery of sequential optical sections through an embryo made at the CHR that had three pronuclei in it after fertilization. The CHR laboratory cultured this embryo for 4 days and it resulted in a blastocyst that seems to be eliminating a chromosomally abnormal cell shown at 11 o’clock (red nucleus).
Figure 4. A similar blastocyst-stage embryo is shown after staining for a muscle protein known as actin. The linear pattern shown defines each of the cell boundaries that make up the outer cells of the trophectoderm that will go on to form the placenta.