Page 93 - The Miracle of Human Creation

THE CREATION OF A HUMAN BEING FROM A CELL

uterine uterine
cavity
cavity
orifice of endometrial
gland duct
blood
trophoblast vessel
blastocyst
en-
inner
cell dometrium
endometrium mass of uterus
of uterus
blastocele
(a) external view, about 5 days after fertilisation (b) internal view, about 6 days after
fertilisation
uterine
cavity
(c) internal view, about 7 days after fertilisation
amniotic
cavity
endometrium
of uterus
(d) photomicrograph

inner
ectoderm
cell
endoderm mass
blastocyst
blood
vessel inner cell mass
endometrium of
blastocele
uterus
With the help of the fallopian tube, a collection of cells (blastocyst) reaches the uterus and
lodges there. It is a round body without a hook or any other attaching mechanism and it is a mir-
acle of creation that it is able to attach itself to the uterus. What allows the embryo to manage
to do this is an enzyme secreted by cells in its outer layer (trophoblasts).

break down the acid layer (hyaluronic acid) in the tissues of the wall of
the uterus. This enables the cells which form the cell cluster to dissolve the
uterine tissue and enter the uterus. Some cells in the cell cluster dissolve

the cells of the uterus, penetrate deeper into it and embed themselves se-
curely in the wall.
As we said earlier, the fact that a cell mass can find the place most su-

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