Structures & Derivaties Flashcards
Nucleus Propulsus
Notochord
Vertebral column
scleroderm of somites
Primordial gut & primordial germ cells derived from?
Primary yolk sac or exocoelomic cavity
Umbilical arteries and vein
Allantois vessels
Placenta derived from?
Decidua basalis (maternal) & Villous Chorion (fetal)
Epidermis & associated glands, CNS, PNS derived from?
Ectoderm
All bone, CT, and muscle
Mesoderm
Epithelial lining of gut tube & associated glands, epithelial lining of resp tract
Endoderm
Paraxial mesoderm gives rise to?
Somites; future vertebrae and ribs, skeletal muscles, dermis, assorted CT
Lateral mesoderm give rise to
Limb skeleton, visceral CT & muscle, serous membranes, heart & blood, spleen, adrenal cortex
Neural tube gives rise to?
CNS, somatic motor portion of PNS, preganglionic sympathetic and parasympathetic pathways
Neural crest cells give rise?
Neurons of PNS with soma in somatic sensory and autonomic ganglia (postganglionic neurons), Schwann cells, meninges, adrenal medulla, melanocytes, odontoblasts, skeletal and CT of neck, truncal and conal ridges (heart), C (parafollicular) cells of thyroid gland
Spinal cord neurons and glial cells derived from?
Ventricular zone
White matter of cord derived from?
Marginal zone
Gray matter (soma of ventral, dorsal, and lateral horns) derived from?
Intermediate zone (mantle layer)
Respiratory tract derived from?
Begins from foregut endoderm during 4th wk
Primary buds of laryngotracheal tube form what?
Main bronchi @ 28 - 35 d
Pseudoglandular stage features?
No resp bronchioles so respiration in baby not possible @ 6-16 wk
Canalicular period features?
Type II alveolar cells produce surfactant @ 20 wk’ some respiration possible late in period (16-26 wk) via terminal saccules;
Terminal sac features?
Alveolar duct branches from resp bronchioles (26 wk to birth); simple cuboidal to simple squamous; capillaries establish close contact; increased surfactant
Alveolar period (32 wk to postnatal) features?
Primitive alveoli with well developed epithelial-endothelial relationships
Pericardial, peritoneal, pleural cavities derived from?
Intraembryonic coelom
Central tendon of diaphram derived from?
Septum transversum (mesoderm)
Diaphram derived from?
4 embyronic components: pleuroperitoneal folds grow in from lateral walls; septum transversum becomes central tendon (migrates from cranial location & receives myoblasts and phrenic nerve while still in cervical region); pleuroperitoneal begin to fuse with dorsal mesentry and septum transversum