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zimovet [89]
3 years ago
8

) During the germinal period, the fertilized ovum duplicates and forms a blastocyst. This hollow ball of cells ________.

Biology
1 answer:
Vedmedyk [2.9K]3 years ago
3 0

Answer:

C - Contains the embryonic disk

Explanation:

After an egg is fertilized, it begins to divide into smaller cells, from the 1 cell stage, to 2, to 4 and so on. Then, on the third day, the cells fall within 16-200 cells and it is then called a <em>morula</em>.

On the fifth day, the morula becomes a ball of calls which is now differentiated into an <em>inner cell mass and a trophectoderm</em>. The inner cell mass becomes the <em>embryo</em> as development goes on and the trophectoderm, becomes the <em>placenta</em>.

As development goes on further, the floor of the amniotic cavity is formed by the embryonic disk, a layer of prismatic cells derived from the inner cell mass.

The embryonic disc develops into 3 layers:

  • Endoderm
  • Mesoderm
  • Ectoderm

There is a major differentiation of cells which gives a template  for the origin of development of specific organs of the embryo.

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