Final answer:
The formation of the blastocyst, a hollow ball of cells, by day 5 post-fertilization is indeed true. This is an important event in early embryonic development.
Answer-True.
Step-by-step explanation:
It is TRUE that a hollow ball of cells known as the blastocyst forms by day 5 post-fertilization. The process begins with a fertilized egg, or zygote, which undergoes a series of divisions creating more cells. By the third day, a cluster of cells known as a morula forms. Around the fifth day, the morula develops into a hollow ball of cells applied the blastocyst. The blastocyst continues to divide and begins the process of implantation into the uterus. The formation of the blastocyst is an important event in the early stages of embryonic development.
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