HeX-Embryoid model showing early blood cells (green) that have formed inside of blood vessels (red) surrounded by yolk sac mesoderm cells (blue) that support these tissues. University of Pittsburgh ...

Gastrulation, the process where an embryo reorganizes itself from a hollow sphere into a multilayered structure, is considered a 'black box' of human development. This is because human embryos are ...

Around eight days after fertilization, the human embryo implants in the endometrium (the tissue that lines the uterus). After implantation, it enters a developmental phase that is not well understood ...

Cellular aggregates derived from human stem cells in previous studies could not be considered genuinely accurate human embryo models, because they lacked nearly all the defining hallmarks of a ...

Isolated from its mother's body, a chicken embryo's only source of food is a golden-yellow dollop of nutrients known simply as yolk. Sustained by the placenta, mammals like ourselves have no need for ...

Epidemiology and Infection, Vol. 103, No. 3 (Dec., 1989), pp. 577-585 (9 pages) Graded doses of live and heat-killed cells of Campylobacter jejuni were injected into the yolk-sac of 5-day-old chick ...

What Is a Yolk Sac? A yolk sac is a small pouch made from thin membranes. The yolk sac is one of the first things to develop during pregnancy and one of the first things your healthcare provider will ...

These colorful embryonic squid are all feeding off yolk sacs within their eggs. Squid develop directly, which means that the embryos have the same basic body plan as an adult squid. Get a closer view ...

Researchers have developed a new embryo-like model derived from adult cells that replicates key features of early human development, including the generation of blood cells. University of Pittsburgh ...