The embryo develops<span> inside an organ called the uterus (womb). It sinks into the soft lining of the uterus and absorbs food from the mother through an organ called the placenta, which </span>develops<span> from the </span>embryo<span>. The uterus has a very stretchy wall so that it can expand as the baby grows.</span>
Science is limited to only providing answers that are observable, testable and repeatable. Most scientific concepts such as evolution or creation are based on faith.
I think the answer is B. look up the defetion of ecosystem.
Answer:
for classifying organisms and studying biodiversity
Explanation:
And endocrine cell is an outer cell i think and a target cell is an antibody which helps attack viruses