Answer:
Different numbers of neutrons
The answer is C. Amniotic membrane. It is the <span>Amniotic membrane that surrounds and protects the embryo. It is the innermost layer of the placenta. it consist thick basement of membrane that protects the embryo from any possible harm.
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Your answer is D I hope this helps ^^
Answer:
False
Explanation:
the amount of neutrons in an atom can vary, which is why we have different types like uranium 242 and 243 etc. regarding how many neutrons it has, some hydrogen have no neutrons as well.