How does the ectoderm tissue develop to form a human body?  

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After fertilization occurs, the fertilized egg (zygote) undergoes many mitotic divisions resulting in the formation of a blastocyst. This stage of an embryo resembles a hollow ball of cells. Eventually, some cells move and form three distinct cell layers within the embryo. This stage is known as gastrulation . The...

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After fertilization occurs, the fertilized egg (zygote) undergoes many mitotic divisions resulting in the formation of a blastocyst. This stage of an embryo resembles a hollow ball of cells. Eventually, some cells move and form three distinct cell layers within the embryo. This stage is known as gastrulation. The gastrula almost resembles a hollow ball that is pushed in on one side. 

Different organs that will be present in the embryo arise from the three primary germ layers of the gastrula. The three layers are ectoderm (outer layer), mesoderm (middle layer) and endoderm (inner layer). These cell layers differentiate into specialized cells and tissues of the body.

The outermost layer or ectoderm cells will form parts of the body including the epidermis (skin), brain and nervous system. The role the ectoderm plays in forming the human body is helping to form essential outer portions like the integumentary system and the nervous system.

Mesoderm cells differentiate into cartilage, bone, blood vessels, muscles and the circulatory system.

Endoderm cells differentiate into the gut or digestive system, respiratory system and excretory system.

The process of gastrulation leads to the development of more specialized cells in the growing embryo.

 

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