Embryology Flashcards
Most common monozygotic twins
Diamnionic-monochorionic thins
Share one placenta, one chorion, but two amniotic fluids
Woman with lower abdominal pains, vaginal bleeding, fever, hCG ~10,000
Ectopic pregnancy
FYI This is a low hCG value
Cloacal membrane
Future anus
VACTERL
Vertebral defects Anal atresia Cardiovascular defects Tracheo Esophageal fistula Renal defects Limb defects
Constellation of symptoms assoc. With abnormal development
VACTERL
Vertebral defects (often sacrococcygeal teratoma) Anal atresia Cardiovascular defects Tracheo Esophageal fistula Renal defects Limb defects
Constellation of symptoms assoc. With abnormal development
Remnant of the ductus Venosus
The Ligamentum venosum
Remnant of the umbilical vein
Ligamentum Teres hepatis
Remnant of the umbilical arteries
Medial umbilical ligaments
MCC of third trimester bleeding
Placenta Previa
Truncus Arteriosus
Forms the aorta and the pulmonary trunk
Bulbus cordis
Forms the smooth parts or the right and left ventricle
Primitive ventricle
Forms the Trabeculated part of the right and left ventricles
Primitive atrium
Forms the Trabeculated parts of the right and left atria
Sinus Venosus
Smooth part of the right atrium
AND
⭐️coronary sinus
Sources of the membranous Interventricular septum (3)
Right bulbar ridge
Left bulbar ridge
AV cushions
1st aortic arch
Maxillary artery
2nd aortic arch
Stapedial artery
3 aortic arch
Right and left CCAs
Right and left ICAs
4th aortic arch
Right subclavian artery (right arch)
Aortic arch (left arch)
6th aortic arch
Right and left pulmonary arteries
Ductus arteriosus
Vitelline arteries in an cult
Form the celiac, SMA, AND IMA
Vitelline veins in an adult
Forms the hepatic veins and sinsuoids, portal vein
Dorsal Mesentary of the stomach in an adult
The greater Omentum
Contents of the Hepatoduodenal ligament
The portal triad
Baby with progressive jaundice, pale stool, dark urine
Biliary atresia; 100% fatal
“Double-bubble sign in newborn”
Possible annular pancreas
Occurs when the ventral pancreatic bud fuses in two locations with the dorsal pancreatic bud
⭐️Have bilious vomit
Midgut rotation
Herniate at week 6, rotates 270 degrees around the SMA, and returns at week 11
Small intestine entirely on right side and large intestine on right
No rotation of the midgut; only completed 90 degrees
Mal rotation of the midgut
SI will be close to the pylorus; pt. at risk for Volvulus
Intestinal atresia
Failed recanalization of the gut tube possibly due to a uterine vascular event
Urorectal septum site in an adult
The perineal body
Upper and lower anal canal derivatives
Upper (above pectinate) cloaca (Hindgut)
Lower-Proctodeum, an invagination of the ectoderm
Ventral mesentary in an adult
The lesser omentum
Metanephros gives rise to…
The functional kidney
Ureteric bud gives rise to…
The ureters, renal pelvis, calyces, and COLLECTING DUCTS
-Ureteric bus begins as an outputching of the mesonephros
Level of the renal arteries
L2
Allantois remnant in adult
Median umbilical ligament
Or
The Urachus
Paramesonephric ducts
Form the Fallopian tubes, uterus, cervix, and superior 1/3 of the vagina
-Is the concept behind adenosis where some of the vagina has columnar epithelia
Embryologic origin of the clit
Phallus
Embryologic origin of the Labia minora
Urogenital folds
Embryologic origin of the labia majora
Labioscrotal swellings
Hyatid cyst of Morgagni
Arises from remnant of the paramesonephroc duct
Didelphys
Lack of fusion of the paramesonephric ducts forms a double uterus
⭐️Bicornate ➡️ Partial fusion
Cells with long telomeres
Stem cells that are constantly replicating
Mesonephric ducts in males
Epididymis, vas deferens, seminal vesicle, Ejaculatory duct
-Also called the Wolffian Ducts
Embryologic origin of the penis
The phallus
Embryologic origin of the ventral penis
Urogenital folds
Embryological origin of the scrotum
Labioscrotal swellings
Sturgeon-Weber Syndrome
Sporadic port-wine Stain Tram track calcium (brain looks outlined on CT) Unilateral (paresis, sensory deficits) Retardation Glaucoma (eye looks fucking HUGE unilaterally) GNAQ Gene Epilepsy
Tuberous sclerosis
Hamartomas in the CNS and skin Angiofibromas of the face, " butterfly" look Ash-leaf spots (hypopigmentation) Rhabdomyoma of the heart Tuberous sclerosis autosomal dOminant MR Angiomyolipomas of the kidney Seizure Shagreen patches (Orange-peel patch) Subungual fibroma
️Germinal Matrix Hemorrhage
At birth, the blood vessels that supply the proliferating neurons and glia above the caudate are thin walled and unable of Autoregulation
➡️ increased BP leads to rupture and hemorrhage
➡️ MR, seizure
⭐️ Tx: Antenatal corticosteroids (just like w/ NRDS)
Bones of the pharyngeal arches
Actually formed by neural crest cells
Arteries and muscles of pharyngeal arches
Formed by mesoderm
Filliform papillae
Only type of tongue papillae that does not have taste buds
Chorda tympani
Branch of the facial nerve that carries taste information
-Is why a ruptured tympanic membrane produces a loss of taste
Inflammatory marker elevated in temporal arteritis
ESR and IL-6
Alar sensory plate
Becomes the DRG
Basal motor plate
Gives rise to motor neuroblasts of the ventral and lateral horns
Filum terminale
Anchors the spinal cord to the coccyx
Arnold-Chiari malformations
The caudal vermis and tonsils of the cerebellum herniate thru the foramen magnum
Clinical: swallowing, strider, loss of gag reflex, vocal cord paralysis (due to loss of CNs IX-XII)
Alar sensory plate
Becomes the DRG
Basal motor plate
Gives rise to motor neuroblasts of the ventral and lateral horns
Filum terminale
Anchors the spinal cord to the coccyx
Arnold-Chiari malformations
The caudal vermis and tonsils of the cerebellum herniate thru the foramen magnum
Clinical: swallowing, strider, loss of gag reflex, vocal cord paralysis (due to loss of CNs IX-XII)
