Gastrulation:

Introduction

Gastrulation is a crucial time in the development of multicellular animals. During gastrulation, several importance things are accomplished:

1. The three primary germ layers are established.
2. The basic body plan is established, including the physical construction of the rudimentary primary body axes.
3. As a result of the movements of gastrulation, cells are brought into new positions, allowing them to interact with cells that were initially not near them. This paves the way for inductive interactions, which are the hallmark of neurulation and organogenesis.

A morphed sequence of drawings from the classic staged diagrams of Nieuwkoop and Faber (19??). This morph was generated and kindly provided by Dr. Steve Black, Reed College.