The embryo and its adnexa (appendages or adjunct parts) or associated membranes (i.e. the products of conception) The conceptus includes all structures that develop from the zygote, both embryonic and extraembryonic. It includes the embryo as well as the embryonic part of the placenta and its associated membranes - amnion, chorion (gestational sac), and yolk sac[WP].

EHDAA2 places this as a subtype of organism. This leads to the inference that a conceptus is an embryo (if an embryo is defined as an organism at embryo stage), which eliminates the embryonic + extra-embryonic = conceptus

embryo plus adnexa

uberon

UBERON:0004716

http://purl.obolibrary.org/obo/uberon.owl, http://purl.obolibrary.org/obo/cl.owl

• embryonic cardiovascular system
• morula
• entire extraembryonic component