by comparing the size of the original plug , the number of cells it contained and the distribution of cells within it to those same features of the grafts in chimeras , we were able to ascertain that , during transformation of the flat neural plate into the closed neural tube ( a period requiring 24 h ) , the graft undergoes a maximum of 3 rounds of craniocaudal extension ( each round of craniocaudal extension was defined as a doubling of graft length , so 3 rounds equaled an 8-fold increase in length ) .
C1521970
features
C1444754
length