Chapter 21.5, Problem 19BYGO

Summary Introduction

To analyze:

The blood vessels that change after birth

Introduction:

The development of blood vessels, both in the embryo and later in life, is called angiogenesis. The first trace of embryonic angiogenesis appears at 13 to 15 days of gestation. At this time, the embryo is a three-layered disc of mesoderm, ectoderm, and endoderm, attached to the uterus by an embryonic stalk and associated with three membranes.