First, they share a common origin: They all develop from mesenchyme, a loose and fluid type of embryonic tissue.

首先，它们都有一个共同的起源：它们都是由间充质（一种松散而流动的胚胎组织）发展而来的。

The researchers say that model contains embryonic tissues and other tissues that can produce structures surrounding the embryo, such as the placenta and yolk material.

研究人员表示，该模型包含胚胎组织和其他可以在胚胎周围产生结构的组织，如胎盘和卵黄物质。

A special gel to simulate embryonic tissue, a warm incubator set at body temperature, and a bit of motion to mimic blood flow.

一种模拟胚胎组织的特殊凝胶，一个设置为体温的温暖培养箱，以及模拟血液流动的一点运动。