Embryonic Nutrition and Placentation

Abstract

Embryonic growth and differentiation can involve considerable costs associated with the production and maintenance of new tissues. Across the vertebrates, a wide variety of strategies have evolved for providing embryos with the energies required during development. Energy substrates can be sequestered prior to fertilization and constitute the entire energy reserve for development, or the substrates provided prior to fertilization may be supplemented by additional materials that are provided during the course of embryonic development.