Which extra-embryonic membrane functions to remove waste from the embryo in n=both birds and mammals?
A - The amnion
B - None of them
C - The allantois
D - The chorion
E - The yolk sac
Answer: C - The allantois
The ALLANTOIS is the sac-like membrane that removes waster from the embryo. In birds, the embryo grows so does this membrane, causing it to eventually press against the chorion, allowing for exchange of oxygen and carbon dioxide to the outside of the shell and as a disposal site for uric acid.