Embryology Flashcards
congenital diaphragmatic hernia is caused by
pleuroperitoneal folds not closing and causing abdominal contents to herniate and compress the lungs
-decrease in unilateral breath sounds
potters sequence
baby has pulmonary hypoplasia, flat facies, lower limb deformities caused by decreased fetal urine output. - there is also frequent decelerations due to the compression of the umbilical cord from the lack of amniotic fluid
may be due to bilateral renal genesis, ACE inhibitors, or posterior urethral valves
amniotic fluid with an increased level of acetylcholinesterase means what
acetylcholinesterase is present in the CSF so if it is leaking into the amniotic fluid during pregnancy this shows that there is an open neural tube defect
neural tube defects occur due to ?
failed fusion of the neural plate during the 4th week of development
fusion of the neural plate begins where
in the cervical region and migrates cranially and caudally
duodenal atresia results from
fialred recanalization of the duodenum die to failure of epithelial call apoptosis
embryonic kidney development begins with the formation of?
nephrogenic cord from the urogenital ridge
the nephrogenic cord develops into what 3 systems
pronephros, mesonephros, metanephros
what is the fate of the pronephros
it is rudimentary and completely regresses
what is the fate of the mesonephros
it regresses in females and becomes the wolffish ducts in males
what does the wollfcan duct create
ductus deferens and the epididymis
what is the fate of the metanephros
mature upper urinary tract
how the the metanephros develop/mature
the metaneprhic diverticulum (ureteric bud) induces the formation of the metanephric blastema
the inductive signals from the ureteric bud (metanephric diverticulum) and the metanephric blastema drives the differentiation.
**both together are the metanephros
what does the metanephric blastema form
glomeruli, bowman space, proximal tubules, loop of hence, and distal convoluted tubules
what does the metanephric diverticulum aka the ureteric bud form
collecting tubules, ducts, major and minor calyces, renal pelvis, and ureters
the beginning go the embryonic stage is marked by _ which establishes
gastrulation
establishes: ectoderm, mesoderm, and endoderm
structures formed from the gastrulation phase regarding to ectoderm, mesoderm and endoderm are
endoderm: Gi tract and lungs
mesoderm: heart, kidneys, spleen
ectoderm: skin and CNS
the CNS develops via neurulation during what weeks
3rd and 4th
neural plate forms the ectoderm and the lateral edges (neural folds) migrate and fuse at the midlines
the thymus derives from the _ pharyngeal pouch and its dorsal wings form to fuse _ while the ventral wings from the _
3rd pharyngeal pouch
inferior parathyroid glands
epithelial structures
the palatine tonsils form from what pouch
2nd
the superior parathyroid glands form from what pouch
fourth pouch
laryngeal cartilage and muscles develop from what pouch
4th and 6th
follicular cells from the thyroid form from what pouch
endodermal out pouching between the 1st and 2nd pouch ( so not a pouch derivative)
parafollicular C cells in the thyroid originate from what pouch
4th pouch
failure of the processes vaginalis can cause what 2 pathologies
indirect inguinal hernias and hydroceles
*both increase in size during the valsalva maneuver
indirect inguinal hernias
abdominal organs pass through the deep inguinal ring and is covered by the internal spematic fascia and located lateral to the inferior epigastric blood vessels
direct inguinal hernia
protrusion of the abdominal contents through a week wall (hesselbach triangle)
**do not pass through the inguinal canal and they are medical to the inferior epigastric blood vessels
hypospadias
incomplete fusion of the urethral folds and presents as a ventrally located urethra
testicular torsion around the
spermatic cord
signs of intestinal obstruction
abdominal distention and bilious emesis
pancreatic duct and bile duct joins and enters the duodenum at the
major dudoenal papillae
ventral pancreatic bud foregut derivatives
unite process and the main pancreatic duct
dorsal bud of the pancreas gives rise to?
pancreatic tail, body, and head
annular pancreas
the ventral bud of the pancreas does not rotate completes and surrounds the second part of the duodenum - obstructs the duodenum and pancreatic drainage
if proximal to the major duodenal papilla there would be non billions emesis- distal there will be villioigs vomiting
Schwann cells are derived from
neural crest cells
_ is the phospholipid component of surfactant that increases late in the third trimester and its presence suggests advanced lung maturity
phosphatidoglycerol
what is phophatidylcholin/lecithin sphingomyelin ration
lipid components of surfaces that signify mature surfacts
lecithin/phosphatidylcholin will rise in the third trimester and sphingomeylein will remain low
**L/S >2 = mature
what is the lamellar body count
these are organelles in the type 2 pneumocystis that store transport and secrete surfactant and is associated with increased surfactant production and lung maturity
what is the highest oxygenated blood in the fetal circulation
umbilical vein leading to the inferior vena cava (from the ductus venous)
uteropelvic junction defect
causes unilateral retal hydronephrosis without ureter dilation
failure to recannalise will cause the proximal ureter to become stenotic
(UPJ is where the kidney meets the ureter)
vesicoureteral junction
where the ureter meets the bladder - obstruction would cause ureter dilation
neck mass anterior to the SCM that has purulent drainage
branchial cleft cysts that is due to pharyngeal cleft/groove incomplete obliteration
2nd pharyngeal groove cysts —branchial cleft cats
melanocytes and Doral root ganglia and sympathetic/parasympathetic ganglia are all derived from
NCC
Homeobox genes (HOX) responsible from
DNA sequences that regulate optioning of embryonic structures
HOX genes code for _ _ that bind regulator regions on DNA
transcription factors
mutations in HOX can lead to
malpositioned body parts
(syndactyly, supernumerary finger)
chromatin cells are derived from
NCC (adrenal medulla)
cyanotic spells that improve with squatting, prominent right ventricular impulse, systolic murmur is consistent with
tetralogy of allot
what causes tetralogy of fallout
antieror and cephalad deviation of the infindiublar septum results in a misaligned VSD and an overriding aorta
in TOF why does squatting improve cyanosis
squatting will increase peripheral vascular resistance and afterload which decreases the right to left shutting ability through the VSD
transposition of the great arteries
failure of spinaling of the aorticopulmonary septum
failed endocardial cushion fusion
causes ASDs or VSDs
- left to right shunt
neural tube defects are caused by a failure in
primary neurulation
myelomeningocele
portions of the spinal cord within the meningeal sac protrude outtrhough a defective vertebral arch
(cystic mass)
myelomeningeoceles are commonly associated with?
downward displacement of the hind brain (chiarri II)
defects in neuronal migration within the cerebral cortex would lead to
lissencephaly or a loss of sulk
skeletal muscle is derived from
mesoderm
pancreatic divisum
ventral and dorsal pancreatic buds do not fuse and cause drainage via 2 operate ducts
in hirschrungs disease the _ is always involved
rectum
incomplete closure of the anterior abdominal wall
gastrochicisis
patent omphalomesenteric duct vis urachus
omphalomesteric: connection between umbilicus and bowel (leakage of stool)
urachus: connection between the umbilicus and bladder (leakage or urine)
leukocyte adhesion deficiency is characterized by impaired _ migration
neutrophil
detective LAD molecules ( umbilical cord late seperation)
deformation
mechanical forces alter shape/position of a structure that was developing normally
** club foot
disruption
destruction of a structure that was previously developing normally
**amniotic band
dysplasia
abnormal organization of cells within a tissue
**skeletal dysplasias
malformation
defect in organosiesis
***spina bifida or holoprosencephaly
holoprosencephaly
incomplete forebrain division into 2 hemispheres (prosencephaly)
