A zygote forms
a. as soon as a sperm cell penetrates an egg cell.
b. when the embryo implants in the uterine wall
c. when a fertilized egg divides to produce two
cells.
d. after at least two divisions of a fertilized egg.
e. after many divisions of a fertilized egg.
Answer: a
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Answer the following statements true (T) or false (F)
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