Term
| What is sonic hedgehog gene responsible for? |
|
Definition
| patterning along the anterior posterior axis |
|
|
Term
| Where is Wnt-7 gene product produced? |
|
Definition
| apical ectodermal ridge (thickened ectoderm at distal end of each limb) |
|
|
Term
| Where is sonic hedgehog gene product produced? |
|
Definition
| base of limbs in zone of polarizing activity |
|
|
Term
| What is the Wnt-7 gene responsible for? |
|
Definition
| proper organization along the dorsoventral axis |
|
|
Term
| Where is the FGF gene produced produced? |
|
Definition
|
|
Term
| What is the function of the FGF gene? |
|
Definition
| stimulates mitosis of underlying mesoderm, providing for lengthening of limbs |
|
|
Term
| What is the funciton of the homeobox genes? |
|
Definition
| involved in segmental organization of embryo in a craniocaudal direction |
|
|
Term
| What occurs if there is a homeobox gene mutation? |
|
Definition
| appendages in wrong locations |
|
|
Term
| By what time does hCG secretion begin? |
|
Definition
| within week 1 after implantation of blastocyst |
|
|
Term
| What happens during week two after fertilization? |
|
Definition
| differentiation into a bilaminar disk (epiblast and hypoblast); two cavities have formed (amniotic cavity and yolk sac); two components to placenta (cytotrophoblast, syncytiotrophoblast) |
|
|
Term
| What happens during week three of fetal development? |
|
Definition
| trilaminar disc; gastrulation; primitive streak, notochord, mesoderm and its organization, and neural plate begin to form |
|
|
Term
| When does the neural tube close? |
|
Definition
|
|
Term
| WHen does the heart begin to beat? |
|
Definition
|
|
Term
| When does the fetus start to move? |
|
Definition
|
|
Term
| When do fetal genitalia have male/female characteristics? |
|
Definition
|
|
Term
| What are the motor and sensory parts of the fetal spinal cord? |
|
Definition
| alar plate is dorsal (lateral) and sensory; basal plate is ventral (medial) and motor |
|
|
Term
| During what days does the fetus go from neural plate to neural tube? |
|
Definition
|
|
Term
| When do the limb buds form? |
|
Definition
|
|
Term
| What is the primitive streak? |
|
Definition
| the epiblast (precursor to ectoderm) invaginates to form a primitive streak; cells from the primitive streak give rise to both intraembryonic mesoderm and part of the endoderm |
|
|
Term
| What is a craniopharyngioma? |
|
Definition
| benign rathke's pouch tumor with cholesterol crystals and calcifications |
|
|
Term
| Where embryologic tissue type does the lens of the eye come from? |
|
Definition
|
|
Term
| What embryologic tissue does the adenohypophysis come from? |
|
Definition
|
|
Term
| What tissue type do the sensory organs of the ear come from? |
|
Definition
|
|
Term
| What embryologic tissue type does olfactory epithelium come from? |
|
Definition
|
|
Term
| What tissues form from neuroectoderm? |
|
Definition
| brain (neurohypophysis, CNS neurons, oligodendrocytes, astrocytes, ependymal cells, pineal gland), retina, spinal cord |
|
|
Term
| Where do parafollicular C cells of the thyroid come from? |
|
Definition
|
|
Term
| Where does the pia and arachnoid matter come from? |
|
Definition
|
|
Term
| Where do ondontoblast come from? |
|
Definition
|
|
Term
| Where do the bones of the skull come from? |
|
Definition
|
|
Term
| What part of the heart is formed by neural crest? |
|
Definition
|
|
Term
| Where do the lungs come from? |
|
Definition
|
|
Term
| Where does the thymus come from? |
|
Definition
|
|
Term
| What embryological tissue does the thyroid follicular cells come from? |
|
Definition
|
|
Term
| What tissue type does the spleen come from? |
|
Definition
|
|
Term
| What tissue type does the eustachian tube come from? |
|
Definition
|
|
Term
| What tissue type does the skin dermis come from? |
|
Definition
|
|
Term
| What tissue type are the gonads derived from? |
|
Definition
|
|
Term
| What kinds of malformations result from mesoderm defects? |
|
Definition
| vertebral, anal atresia, cardiac, tracheoesophageal fistula, renal defects, limb defects |
|
|
Term
| What is the difference between aplasia and agenesis? |
|
Definition
| agenesis= absent organ due to absent primordial tissue; aplasia= absent organ despite present primordial tissue |
|
|
Term
| What are the teratogenic effects of alkylating agents? |
|
Definition
| absence of digits, multiple anomalies |
|
|
Term
| What are the effects of aminoglycosides on fetus? |
|
Definition
| cranial nerve VIII toxicity |
|
|
Term
| What are the effects of carbamazepine on a fetus? |
|
Definition
| NTDs, craniofacial defects, fingernail hypoplasia, developmental delay, IUGR |
|
|
Term
| What are the teratogenic effects of phenytoin? |
|
Definition
| fetal hydantoin syndrome: microcephaly, dysmorphic craniofacial features, hypoplastic nails and distal phalanges, cardiac defects, IUGR, mental retardation |
|
|
Term
| What are the teratogenic effects of valproate? |
|
Definition
| inhibition of maternal folate absorption--> NTDs |
|
|
Term
| What are the teratogenic effects of warfarin? |
|
Definition
| bone deformities, fetal hemorrhage, abortion, opthalmologic abnormalities |
|
|
Term
| What are the effects of cocaine on the fetus? |
|
Definition
| abnormal fetal development and fetal addiction; placental abruption |
|
|
Term
| What are the effects of smoking on the fetus? |
|
Definition
| preterm labor, placental problems, IUGR, ADHD |
|
|
Term
| What are the effects of maternal diabetes on the developing fetus? |
|
Definition
| caudal regression (anal atresia to sirenomelia), congenital heart defects, neural tube defects |
|
|
Term
| What are the effects of excess vitamin A on the fetus? |
|
Definition
| high ghigh risk for spontaneous abortions and birth defects (cleft palate and cardiac abnormalities) |
|
|
Term
| What are the effects of xrays on a fetus? |
|
Definition
| microcephaly, mental retardation |
|
|
Term
| What is teh mechanism by which alcohol is teratogenic? |
|
Definition
| inhibition of cell migration |
|
|
Term
| What are the specific anomalies associated with FAS? |
|
Definition
| developmental retardation, microcephaly, holoprosencephaly, facial abnormalities, limb dislocation, and heart and lung fistulas |
|
|
Term
| Describe the number of chorions/amnions for dizygotic twins. |
|
Definition
|
|
Term
| Describe the number of chorions/amnions for monozygotic twins? |
|
Definition
| if splits during days 0-4= dichorionic diamniotic with either fused or separate placenta (25%); 4-8 days= monochorionic diamnionic (75%); 8-12 days= monochorionic monoamniotic (<1%); >13 days= monochorionic monoamniotic conjoined twins |
|
|
Term
| What is the purpose of beta hCG? |
|
Definition
| stimulate corpus luteum to secrete progesterone during first trimester |
|
|
Term
| What is the maternal component of the placenta? |
|
Definition
| decidua basalis (derived from endometrium; maternal blood in lacunae) |
|
|
Term
| What is the significance of a single umbilical artery? |
|
Definition
| congenital and chromosomal anomalies |
|
|
Term
| Where do the umbilical arteries connect to? |
|
Definition
| fetal internal iliac arteries to placenta |
|
|
Term
| Where does teh umbilical vein connect? |
|
Definition
|
|
Term
| What are the umbilical arteries and veins derived from? |
|
Definition
|
|
Term
| Where does the allantois come from and what does it form? |
|
Definition
| comes from the yolk sac in the third week and extends into the urogenital sinus; becomes the urachus, a duct between teh bladder and yolk sac |
|
|
Term
| What happens if the urachus does not obliterate? |
|
Definition
| patent urachus or vesicourachal diverticulum (outpouching of bladder) |
|
|
Term
| What is the viteline duct? |
|
Definition
| aka omphalomesenteric duct; connects the yolk sac to midgut lumen (obliterates in the 7th week) |
|
|
Term
| What is a vitelline fistula? |
|
Definition
| failure of duct to close leading to meconium discharge from the umbilicus |
|
|
Term
| What does the bulbus cordis give rise to? |
|
Definition
| right ventricle and smooth parts (outflow tract) of left and right ventricle |
|
|
Term
| What does the primitive ventricle form? |
|
Definition
| trabeculated left and right ventricle |
|
|
Term
| What structure does teh primitive atria form? |
|
Definition
| trabeculated left and right atrium |
|
|
Term
| What does the sinus venosus give rise to? |
|
Definition
| left horn= coronary sinus; right horn= smooth part of the right atrium |
|
|
Term
| What fetal structures give rise to the SVC? |
|
Definition
| right common cardinal vein and right anterior cardinal vein |
|
|
Term
| Describe the formation of the aorticopulmonary septum. |
|
Definition
| neural crest migration -> truncal bulbar ridges that spiral and fuse |
|
|
Term
| What heart defects are due to defective formation of the aorticopulmonary septum? |
|
Definition
| transposition of the great vessels, tetralogy of fallot, persistant TA |
|
|
Term
| Describe the formation of the interventricular septum? |
|
Definition
| muscular ventricular septum forms; opening is called interventricular foramen; AP septum meets and fuses with muscular ventricular sptum to form membranous interventricular septum, closing interventricular foramen |
|
|
Term
| What do the endocardial cushions do during heart development? |
|
Definition
| growth of endocardial cushions separates atria from ventricles and contributes to both atrial separationand membranous portion of the interventricular septum |
|
|
Term
| What forms the valve of the the foramen ovale/ |
|
Definition
|
|
Term
| What causes a patent foramen ovale? |
|
Definition
| excessive resorption of septum primum and/or secundum |
|
|
Term
| Where does fetal erythropoesis occur? |
|
Definition
| 3-8 weeks= yolk sac; 6-30 weeks= liver; 9-28 wks= spleen; bone marrow= 28 weeks onward |
|
|
Term
| What are the globin chains that make up fetal hb? |
|
Definition
|
|
Term
| Where does the ductus arteriosus connect? |
|
Definition
| aorta (distal to left subclavian) to branch of right and left pulmonary artery |
|
|
Term
| Closed foramen ovale is called... |
|
Definition
|
|
Term
| What causes closure of teh ductus arteriosus? |
|
Definition
| increase in O2 leads to decrease in prostaglandins, causing closure of ductus arteriosus |
|
|
Term
| Adult derivative of the umbilical vein? |
|
Definition
| ligamentum teres hepatis contained in the falciform ligament |
|
|
Term
| What are the derivatives of the umbilical arteries? |
|
Definition
| medial umbilical ligaments |
|
|
Term
| What is a derivative of the ductus arteriosus? |
|
Definition
|
|
Term
| What is the adult derivative of the ductus venosus? |
|
Definition
|
|
Term
| What is teh adult derivative of the allantois? |
|
Definition
| urachus-median umbilical ligament |
|
|
Term
| What does the telencephalon become? |
|
Definition
| wall= cerebral hemispheres; cavities= lateral ventricles |
|
|
Term
| What does the diencephalon become? |
|
Definition
| walls= thalamus; cavities= third ventricle |
|
|
Term
| What does the mesencphalon become? |
|
Definition
| walls= midbrain; cavities= aqueduct |
|
|
Term
| What does the metencephalon become? |
|
Definition
| walls= pons and cerebellum; cavities= upper part of fourth ventricle |
|
|
Term
| What does the myelencephalon become? |
|
Definition
| medulla and lower part of fourth ventricle |
|
|
Term
| What are the associated findings of anencephaly? |
|
Definition
| elevated AFP and polyhydramnios |
|
|
Term
| What is a chiari II malformation? |
|
Definition
| cerebella tonsillar herniation through foramen magnum with aqueductal stenosis and hydrocephaly; often presents with syringomyelia, thoraco-lumbar meningocele |
|
|
Term
| What is dandy walker syndrome? |
|
Definition
| large posterior fossa; absent cerebellar vermis with cystic enlargement of 4th ventricle; can lead to hydrocephalus and spina bifida |
|
|
Term
| What are teh symptoms of syringomyelia? |
|
Definition
| crossing fibersof spinothalamic tract are typically damaged first leading to "cape-like" biltareal loss of pain and temperature sensation in upper extremities with preservation of touch sensation |
|
|
Term
| Where is syringomyelia most commonly located? |
|
Definition
|
|
Term
| Derivative of the first aortic arch? |
|
Definition
| part of the maxillary artery (branch of external carotid) |
|
|
Term
| What is the derivative of the second aortic arch? |
|
Definition
| stapedial artery and hyoid artery |
|
|
Term
| What are the derivatives of the third aortic arch? |
|
Definition
| common carotid artery and proximal part of internal carotid artery |
|
|
Term
| What is the derivative of the fourth aortic arch? |
|
Definition
| on left aortic arch; on right proximal part of right subclavian artery |
|
|
Term
| What are the derivatives of the sixth aortic arch? |
|
Definition
| proximal part of pulmonary arteries and (on left only) ductus arteriosus |
|
|
Term
| What vessels are close to the recurrent laryngeal nerves? |
|
Definition
| righ recurrent laryngeal loops around the branch point of the brachiocephalic artery into right common carotid and right subclavian; left recurrent laryngeal loops around ductus arteriosus |
|
|
Term
| What's another name from branchial clefts? |
|
Definition
|
|
Term
| Which branchial aparatuses are derived from each type of embryonic tissue? |
|
Definition
| clefts/grooves= ectoderm; arches= mesoderm (muscles arteries) and neural crest (bones and cartilage); pouches= endoderm |
|
|
Term
| What are the branchial cleft derivatives? |
|
Definition
| first cleft develops into external auditory meatus; second through 4th forms the temporary cervical sinuses which are obliterated by proliferation of 2nd arch mesenchyme |
|
|
Term
| What are the derivatives of the first branchial arch? |
|
Definition
| meckel's cartilage; mandible, malleus, incus, sphenomandibular ligament |
|
|
Term
| What muscles are derived from teh first branchial arch? |
|
Definition
| muscles of mastication, myelohyoid, anterior belly of digastric tensor tympani, tensor veli palatini |
|
|
Term
| What are the nerves derived from teh first branchial arch? |
|
Definition
|
|
Term
| What is Treacher Collins syndrome? |
|
Definition
| first arch neural crest fail to migrate leading to mandibular hypoplasia and facial abnormalities |
|
|
Term
| What are the cartilage derivatives of the second branchial arch? |
|
Definition
| richert's cartilage: stapes, styloid process, lesser horn of hyoid, stylohyoid ligament |
|
|
Term
| What are the muscular derivatives of the second branchial arch? |
|
Definition
| muscles of facial expression, stapedius, stylohyoid, posterior belly of digastric |
|
|
Term
| What nerves are derived from teh second branchial arch? |
|
Definition
|
|
Term
| What are the cartilage derivatives of the third branchial arch? |
|
Definition
| cartilage; greater horn of the hyoid |
|
|
Term
| What are the muscular derivatives of the third branchial arch? |
|
Definition
|
|
Term
| What are the nerves associated with the third branchial arch? |
|
Definition
|
|
Term
| What is a congenital pharyngocutanous fistula? |
|
Definition
| persistance of third cleft and pouch causing a fistula between the tonsillar area and a cleft in the lateral neck |
|
|
Term
| What are the cartilage derivates of the 4-6 branchial arches? |
|
Definition
| thyroid, cricoid, arytenoids, corniculate, cuneiform |
|
|
Term
| What are the muscles of the 4-6 branchial arches? |
|
Definition
fourth= most pharyngeal constrictors: cricothyroid, levator veli palatini
sixth= all intrinsic muscles of larynx except cricothyroid |
|
|
Term
| Which nerves ar derived from the fourth and sixth branchial arches? |
|
Definition
fourth= CN X (superior laryngeal branch)
sixth= CN X (recurrent laryngeal branch) |
|
|
Term
| Which branchial arches form the tongue? |
|
Definition
| branchial arch 1 makes the anterior 2/3rds of the tongue; branchial arches 4-6form the posterior 1/3 of the tongue |
|
|
Term
| Which branchial arch has no derivatives? |
|
Definition
|
|
Term
| What are teh derivatives of the first branchial pouch? |
|
Definition
| middle ear cavity, eustachian tube, mastoid air cells |
|
|
Term
| What are the derivatives of the second branchial pouch? |
|
Definition
| epithelial lining of palatine tonsil |
|
|
Term
| What are teh derivatives of the third branchial pouch? |
|
Definition
| dorsal wings= inferior parathyroids; ventral wings= thymus |
|
|
Term
| What are the derivatives of the fourth branchial pouch? |
|
Definition
| dosral wings develop into superior parathyroids |
|
|
Term
| The parafollicular cells of the thyroid are derived from what pouches? |
|
Definition
| neural crest cells associated with the fourth and fifth pharyngeal pouches |
|
|
Term
| What supplies taste sensation to the tongue? |
|
Definition
| VII to teh anterior 2/3rds; IX for posterior 1/3; X for extreme posterior |
|
|
Term
| What nerves provide touch sensation to the tongue? |
|
Definition
| V3 for anterior 2/3rds; posterior 1/3 is IX; extreme posterior is X |
|
|
Term
| What nucleus in the brain mediates taste from the tongue? |
|
Definition
|
|
Term
| Which myotomes are the muscles of the tongue derived from? |
|
Definition
|
|
Term
| The thyroglossal duct may persisa as... |
|
Definition
| pyramidal lobe of thyroid |
|
|
Term
|
Definition
| normal remnant of the thyroglossal duct |
|
|
Term
| Where is the most common site of ectopic thyroid tissue? |
|
Definition
|
|
Term
| What are the symptoms of a thyroglossal duct cyst? |
|
Definition
| midline neck; moves with swallowing |
|
|
Term
| Cleft lip is due to a failure of fusion of what structures? |
|
Definition
| maxillary and medial nasal processes (formation of primary palate) |
|
|
Term
| A cleft palate results from failure of fusion of what structures? |
|
Definition
| lateral palatine processes, nasal septum, and/or median palatine process (formation of secondary palate) |
|
|
Term
| What abdominal wall defect is associated with protrussion of the liver? |
|
Definition
| omphalocele (rarely associated with gastroschisis) |
|
|
Term
| Failure of rostral wall closure= |
|
Definition
|
|
Term
| Failure of lateral fold closure- |
|
Definition
| omphalocele, gastroschisis |
|
|
Term
| Failure of caudal fold closure= |
|
Definition
|
|
Term
| What is apple peel atresia? |
|
Definition
| jejunal, ileal, colonic atresia that is due to vascular accident |
|
|
Term
| What part of the gut herniates through the umbilical ring? |
|
Definition
|
|
Term
| When does the midgut herniate? return? |
|
Definition
|
|
Term
| The midgut rotates around the ____ while it herniates during development. |
|
Definition
|
|
Term
| What is tyep A trachioesophageal fistula? |
|
Definition
|
|
Term
| what is type B tracheoesophageal fistula? |
|
Definition
| proximal esophagus is attached to trachea and distal esophagus is a blind tube |
|
|
Term
| What is type C tracheoesophageal fistula? |
|
Definition
| proximal esophagus ends in a blind pouch and distal esophagus connects to trachea |
|
|
Term
| When does pyloric stenosis present? |
|
Definition
|
|
Term
| What is the incidence of congenital pyloric stenosis? |
|
Definition
|
|
Term
| What embryologic structure is the pancreas derived form? |
|
Definition
|
|
Term
| What does the ventral pancreatic bud form? |
|
Definition
|
|
Term
| What does the dorsal pancreatic bud form? |
|
Definition
| body, tail, isthmus, and accessory pancreatic duct |
|
|
Term
| What forms the main pancreatic duct? |
|
Definition
| dorsal and ventral pancreatic buds contribute to the main pancreatic duct |
|
|
Term
| What forms the head of the pancreas? |
|
Definition
| both the ventral and dorsal pancreatic bud |
|
|
Term
| What is an annular pancreas? |
|
Definition
| ventral bud abnormally encircles second part of duodenum; forms a ring of pancreatic tissue that may cause duodenal narrowing |
|
|
Term
| What is pancreas divisum? |
|
Definition
| ventral and dorsal parts fail to fuse at 8 weeks |
|
|
Term
| Where does teh spleen arise from? |
|
Definition
| dorsal mesntery and hence is of mesodermal origin but supplied by celiac artery |
|
|
Term
| When does the pronephros degenerate? |
|
Definition
|
|
Term
| During what time does the mesonephros function as an interim kdiney? |
|
Definition
|
|
Term
| When does the metanephros first appear? |
|
Definition
|
|
Term
| When is nephrogenesis complete? |
|
Definition
|
|
Term
| When is the ureteric bud structures fully canalized? |
|
Definition
|
|
Term
| What induces differentiation of metanephric mesenchyme? |
|
Definition
|
|
Term
| where does the ureteric bud derivatives end and mesonephric derivatives begin? |
|
Definition
| ureteric bud forms up through collecting duct; mesonephros forms down through distal tubules |
|
|
Term
| What is the most common site of urinary obstruction in fetuses? |
|
Definition
| ureteropelvic junction (last to canalize) |
|
|
Term
| What causes potter's syndrome? |
|
Definition
| malformation sof the ureteric bud |
|
|
