The diploid number is restored when the two haploid cells combine to create a zygote. Basically when the sperm cell enters the egg cell and makes the offspring.
D is the answer. A gene is a part of a chromosome.
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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