Chapter 43.5, Problem 2R

Summary Introduction

To review:

The origin of the placenta in mammals.

Introduction:

The developing embryo requires a constant supply of nutrients and exchange of gases and wastes. In animals, such as humans, the development of the embryo occurs inside the body of the mother. Thus, there is a formation of an organ called the placenta, which aids in the attachment of the embryo to the uterine wall of the mother. The mammals with the presence of placenta are referred to the placental mammals.