A. an initial random selection made at each cell division as to whether the new cells
are of the anterior or posterior type in the early embryo. At a particular point in
development, all the “anterior” cells groups together, as do all the “posterior”
cells. The axis is formed.
B. the early embryonic cells responding to the effect of the magnetic field on the
metal-containing proteins and other molecules supplied by the mother in the egg.
C. how soon after fertilization the first cell division occurs in the embryo. If the first
embryonic divisions occur shortly after fertilization, they yield cells of the
“anterior” type, with “posterior” type cells being generated later. The opposite
happens if the first cleavage is more than 10 hours (humans) after fertilization.
D. the early embryonic cells responding to chemical gradients in the egg provided by
the mother. (Maternal effect.)
E. whether the pregnant mother sleeps on one of her sides (anterior towards the
“top” of the fertilized egg), or if she sleeps on her back or stomach (posterior
towards the top).
are of the anterior or posterior type in the early embryo. At a particular point in
development, all the “anterior” cells groups together, as do all the “posterior”
cells. The axis is formed.
B. the early embryonic cells responding to the effect of the magnetic field on the
metal-containing proteins and other molecules supplied by the mother in the egg.
C. how soon after fertilization the first cell division occurs in the embryo. If the first
embryonic divisions occur shortly after fertilization, they yield cells of the
“anterior” type, with “posterior” type cells being generated later. The opposite
happens if the first cleavage is more than 10 hours (humans) after fertilization.
D. the early embryonic cells responding to chemical gradients in the egg provided by
the mother. (Maternal effect.)
E. whether the pregnant mother sleeps on one of her sides (anterior towards the
“top” of the fertilized egg), or if she sleeps on her back or stomach (posterior
towards the top).