Discuss the two types of embryonic folding. What is accomplished by each type of folding?
What will be an ideal response?
The first type of folding, cephalocaudal, occurs in the head and tail regions of the embryo. Cephalocaudal folding creates the future head and buttocks regions of the embryo. The second type of folding, transverse, or lateral, folding, occurs when the left and right sides of the embryo curve and fold toward the midline. As the sides move closer together, the yolk sac is pinched off, leaving only a small area of the endoderm called the vitelline duct. Transverse folding creates the future trunk region and almost immediately forms the primitive gut, which later becomes the digestive tract inside the abdominal cavity.
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Answer the following statement true (T) or false (F)
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