Organogenesis of major body systems Flashcards
In what weeks of gestation does organogenesis occur?
Weeks 3-8
When does organogenesis occur relative to gastrulation, and why?
End of gastrulation is the start point of organogenesis
Embryo folding occurs to move the ectoderm, mesoderm and endoderm in their correct anatomical positions for the designated organs to develop
What is embryo folding, and why it important for organogenesis?
Embryo folding: trilaminar germ disc curls and grows rapidly
Moves the ectoderm, mesoderm and endoderm in their correct anatomical positions for the designated organs to develop
In which directions does embryo folding occur, and what embryonic shape does this result in?
Cylindrical, C-shaped trilaminar germ disc
How does the ectoderm contribute to the skin formation?
Skin epidermis
What germ layer of the trilaminar germ disc forms hair, in organogenesis?
Ectoderm
What germ layer of the trilaminar germ disc forms nails, in organogenesis?
Ectoderm
How does the ectoderm contribute to formation of the teeth?
Teeth enamel
What germ layer of the trilaminar germ disc forms nervous systems, in organogenesis?
Ectoderm
CNS and PNS
How does the ectoderm contribute to formation of the head region in 3 ways?
Eyes
Ears
Connective tissues of head
Which germ layer causes formation of neural tube and neural crest cells in organogenesis?
Ectoderm
Dorsal folding causes neural tube formation, during this ectodermal cells detach from neural plate and become neural crest cells
Mesoderm forms the epithelial linings of which 3 major body systems?
Respiratory
GI
Biliary (gallbladder, bile ducts)
How does mesoderm contribute to the formation of the bladder and urethra?
Epithelial lining
Which germ layer forms the GI tract in organogenesis?
Endoderm
Glands opening into GI tract, glands of pancreas and liver
What germ layer forms the skeleton and bones, and another structure that connects to the musculoskeletal system?
Mesoderm
Skeletal muscles, skeleton and bones
