Somites develop from
Ans. a (Paraxial mesoderm) (Ref. Human Embryology by IB Singh; 6th/ pg. 46)# Splanchnopleuric mesoderm (from lateral plate mesoderm) forms mesothelial covering of visceral organs;# Intermediate plate mesoderm forms urinary and genital systems, adrenal cortex;# Somites that are derived from paraxial mesoderm form the axial skeleton, voluntary musculature, etc.DERIVATIVES OF THE MESODERMAL GERM LAYERRegions of the epiblast that migrate and ingress through the primitive streak have been mapped and their ultimate fates determined, as appended below:# Cells that ingress through the cranial region of the node become notochord;# Those migrating at lateral edges of node and from cranial end of the streak become paraxial mesoderm:# Cells migrating through the midstreak region become intermediate mesoderm:# Those migrating through the more caudal part of the streak form lateral plate mesoderm: and# Cells migrating through the caudal-most part of the streak contribute to extraembrvonic mesoderm.# Intermediate mesoderm connects paraxial and lateral plate mesoderm.Additional educational point:# Sclerotomes give rise to vertebral arches (dorsal sclerotome), vertebral bodies (ventral sclerotome), base of the skull, costal processes and ultimately ribs (in thoracic region).
Paraxial mesoderm
Lateral plate mesoderm
Intermediate mesoderm
Extra-embryonic coelom
Fertilization and Development of Embryo