13.11 Post-Implantation Development Flashcards
What is gastrulation?
when the three primary germ layers become distinct
What are the three primary germ layers?
ectoderm
mesoderm
endoderm
What is the archenteron?
primitive gut cavity
What does the blastospore give rise to?
anus
What structures are formed from the ectoderm?
nervous system
pituitary gland
adrenal medulla
cornea and lens
epidermis
nasal, oral, and anal epithelium
What structures are formed from the mesoderm?
muscle
bone
connective tissue
cardiovascular system
lymphatic system
urogenital organs
dermis of skin
What structures are formed from the endoderm?
gi tract and epithelium
GI glands
respiratory epithelium
epithelial lining of urogenital organs and ducts
urinary bladder
What is neurulation?
formation of the nervous system
When does neurulation occur?
after gastrulation
When does neurulation begin?
when a portion of the ectoderm differentiates into the neural plate
What does the neural tube eventually develop into?
central nervous system
What cell types do the neural crest cells develop into?
melanocytes
glial cells
adrenal medulla
peripheral neurons
facial connective tissue
What is the notochord?
mesoderm that gives rise to the vertebral column
What is organogenesis?
development of organ systems
When does the embryo become known as the fetus?
8th week when major organ systems are present
