CMMB 403 - Deferred final exam with complete solutions 2024/2025

CMMB 403 - Deferred final examA. At 13 days after fertilization WHERE are the progenitor cells that will eventually proliferate and differentiate to form the ventricles of the human heart? they are in the epiblast since this is during the bilaminar stage for a human embryo - before gastrulation has started. describe the key signals, cell and tissue movements that result in the formation of the ventricular region of the heart from the cells in part A up to about day 28 after fertilization. the cells that become the heart ingress thru the middle part of the primitive streak and become part of the splanchnic lateral plate mesoderm where they are specified to become cardiogenic mesoderm by WNT inhibitors (crescent), BMP's and Fgf8 all from the underlying anterior endoderm. the specification occurs in two lateral patches of the cell within the splanchnic lateral plate mesoderm. after specification the heart progenitors are brought to the midline by embryonic folding and they will form two tubes which fuse to form a single medial heart tube. cells that will form the ventricles are anterior and exposed to low retinoic acid (RA). then the heart tube loops so the ventricles become posterior. Brainpower Read More Previous Play Next Rewind 10 seconds Move forward 10 seconds Unmute Full screen