Do all mammals contain a placenta

Do all mammals contain a placenta?

E

Expert

Verified

Mammals of the monotreme group (that is, platypus and echidnas) are oviparous, egg-laying, and they do not encompass a placenta. Mammals of the marsupial group (that is, kangaroos, koalas and opossums) do not contain a placenta either; females of this group give birth to embryonic young that then carry on growth in the mother’s pouch. Placenta just forms in female placental mammals.

   Related Questions in Biology

©TutorsGlobe All rights reserved 2022-2023.