Answer:
By looking at human embryo we can determine that it has a postanal tail.
Explanation:
Human embryo is a a process of life cycle that takes place after the fertilization. It takes 9 months for a human embryo to be fully developed. If we take a look at a human embryo, we will notice that it has a postanal tail.
Postanal tail is simply an extension of body. It is only during the embryonic stage that the postanal tail can be found. After the birth this feature cannot be found.
Answer:
I think its chemical energy is not required because passive transport doesn't need energy at all
