biology notes

The Great Divide

Cephalic furrow the early foldDivides the embryo in one go.Pulling in on its ownDeep it sinks into the yolk. This great divide of tissue foldSplits the embryo in back and front.But why the furrow once it growsStretches flat and gone it goes? A fold that folds and then unfoldsLeave us wondering what’s the role.