Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
89 Cards in this Set
- Front
- Back
|
Fxn of sonic hedgehog gene? Where produced?
|
Patterning along ant-post axis. Produced at base of limbs in zone of polarizing activing.
|
|
|
Fxn of Wnt-7 gene? Where produced?
|
Patterning along dorsal-ventral axis. Produced at apical ectodermal ridge (thick ectoderm at distal end each developing limb)
|
|
|
Fxn of FGF gene? Where produced?
|
Stimulates mitosis of underlying mesoderm, allowing limb lengthening. Produced at apical ectodermal ridge.
|
|
|
Fxn of homeobox gene?
|
Segmental org of embryo in craniocaudal direction.
|
|
|
What are the names of dividing zygote as progresses to implantation?
|
Zygote, morula, blastocyst
|
|
|
When does hCG start to be secreted? Who secretes it?
|
Within 1 week after implantation of blastocyst in endometrium. Syncytiotrophoblast.
|
|
|
What happens at week 2, week 3 of embryogenesis?
|
Week 2: Bilaminar disk (epiblast, hypoblast)
Week 3: Gastrulation (endo, meso, ectoderm) |
|
|
How does the neural tube form? When does it close? What does the notocord become in adults?
|
Notocord induces overlying ectoderm to form neuroectoderm and neural plate. Neural crest cells of neural plate migrate in and form loop, pinch off. Neural tube closes by week 4. Nucleus pulposus of intervertebral disk in adults.
|
|
|
When is the embryonic period? What happens during this time?
|
Week 3-8. Organogenesis, susceptible to teratogens!
Week 4: heartbeat, neural tube closure, limbs begin to form |
|
|
When is the fetal period?
When does baby have male/female genitalia? |
Week 8+, fetal movement
Week 10 |
|
|
What are the alar and basal plates, what is their orientation?
|
Alar plate - dorsal, sensory
Basal plate - ventral, motor (just like the orientation of the spinal cord!) |
|
|
Where does the primitive streak come from? What does it give rise to?
|
Epiblast (ectoderm) invaginates to become primitive streak, which gives rise to mesoderm and part of endoderm.
|
|
|
What does the surface ectoderm give rise to?
|
"elasoos"
epidermis lens adenohypophysis (ant pit) sensory organs of ear olfactory epi oral cavity epi lining salivary/sweat/mammo glands |
|
|
What does the neuroectoderm give rise to?
|
CNS: Brain, retina, spinal cord
neurohypophysis (post pit) |
|
|
Neural crest derivatives?
|
ANS, DRG, CN's, celiac ganglion, Schwann cells, pia and arachnoid
Melanocytes Chromaffin cells adrenal medulla Parafollicular C cells of thyroid Bones of skull Odontoblasts Aorticopulm septum |
|
|
What does the endoderm give rise to?
|
"GT PLT" - get a plate for the GI tract...
GI tract epithelium, liver, panc Thymus Parathyroid Lungs Thyroid follicular cells |
|
|
What does mesoderm give rise to?
|
"MS. Sally Gives HEAD"
Muscle, bone, CT Serous linings of body cavity spleen GU system heart, blood, lymphatics eustachian tube adrenal cortex dermis of skin |
|
|
Malformation vs deformation?
|
Malformation - intrinsic defect
Deformation - extrinsic cause |
|
|
Agenesis vs Aplasia?
|
Agenesis - no primordial tissue, no growth
Aplasia - primordial tissue present but no growth |
|
|
Fetal Alchohol Syndrome - features of baby?
|
Smooth philtrum, hypertelorism, thin upper lip, MR
|
|
|
When are the chorion and amnion formed?
Progression of types monozygotic twinning? |
Chorion-day 3
Amnion-day8 Di-Di, Monochoro Diamnio, Mono Mono |
|
|
What are fetal components of the placenta? Fxns?
|
Cytotrophoblast: inner layer chorionic villi
Syncytiotrophoblast: outer layer, makes hCG to support progesterone in 1st tri |
|
|
What is the maternal component of the placenta?
|
Decidua basalis of the endometrium. Blood fills lacunae that the chorionic villi stick their fingers into.
|
|
|
What is the umbilicus derived from?
|
Yolk sac-->allantois-->urachus. Urachus is duct btwn bladder and yolk sac (which later falls off and just is umbilicus).
|
|
|
What happens if the urachus fails to close?
|
Patent urachus - urine comes out umbilicus
Vesicourachal diverticulum - outpouching of bladder |
|
|
What connects the yolk sac to the midgut lumen? When does it obliterate?
|
Vitelline duct/omphalomesenteric duct. Week 7.
|
|
|
What happens if the vitelline / omphalomesenteric duct doesn't close?
|
Vitelline fistula: shit comes out of umbilicus
Meckel's diverticulum: outpouching of ileum |
|
|
Truncus arteriosus gives rise to what heart structure?
Explain how the truncus arteriosus develops? |
Ascending aorta and pulm trunk
Neural crest, truncal and bulbar ridge, spiral down, aorticopulm septum, truncus arteriosus |
|
|
Bulbus cordis
|
RV and smooth outflow tract of RV and LV
|
|
|
Primitive ventricle
Primitive atria |
Trabeculated part of RV and LV
Trabeculated RA and LA |
|
|
Left horn of sinus venosus
Right horn of sinus venosus |
L - coronary sinus
R - smooth part of RA |
|
|
R common cardinal v and R anterior cardinal v
|
SVC
|
|
|
Describe 3 pathologies of the truncus arteriosus?
|
1. Transposition of the great vessels (failure to spiral)
2. TOF (skewed aorticopulm septum dev) 3. Persistent TA (partial aorticopulm septum dev) |
|
|
How does the interventricular septum develop?
|
Muscular ventricular septum grows up from bottom, and aorticopulm septum grows down from top. Then endocardial cushions fill in the space and separate atria, contribute to membranous portion.
|
|
|
How does the interatrial septum develop?
|
Septum primum grows down and gets hole in it (foramen secundum). Then septum secundum grows down to create permanent foramen ovale. Septum primum regresses and joins with septum secundum to form final interatrial septum.
|
|
|
What causes patent foramen ovale?
|
Excessive resorption of septum primum and septum secundum.
|
|
|
Where does fetal erythropoiesis occur and when?
|
"Young Liver Synthesizes Blood"
Yolk sac 3-8 Liver 6-30 Spleen 9-28 BM 28+ **around 1st, 2nd, 3rd tri |
|
|
Where is the most oxygenated blood in the fetal circ? What is the ox sat in this blood?
|
Umbilical v, ductus venosus...then mixing occurs in RV. O2 sat still only 80%.
|
|
|
Where is the least oxygenated blood in the fetal circ?
|
Leg veins and SVC (coronary sinus?)
Blood in umbilical artery still has some O2 in it, comes directly off of internal iliac arteries. |
|
|
What happens when infant takes first breath?
|
Decrease pulm resistance, decrease RA pressure. Now RAP<LAP, so blood shunted opposite way, closing the foramen ovale into fossa ovalis. Increase oxygen also decreases PG's, closing PDA.
|
|
|
What are the parts of the prosencephalon, what do they become?
|
Telencephalon - cerebral hem
Diencephalon - thalami, etc |
|
|
What are the parts of the mesoencephalon, what do they become?
|
Midbrain
|
|
|
What are the parts of the rhomboencephalon, what do they become?
|
Metencephalon- pons, cerebellum
Myelencephalon - medulla |
|
|
Define holoprosencephaly? Associated causes?
|
Failure of 2 hemispheres to separate, causes cyclopia. Assoc with Trisomy 13, FAS, cleft lip/palate.
|
|
|
What is a Chiari II malformation? What often presents with it?
|
Cerebellar tonsillar hernation with aqueductal stenosis and hydrocephalus.
Myelomeningocele, syringomyelia. |
|
|
What is Dandy-Walker malformation?
|
Large posterior fossa with absent cerebellar vermis and cystic enlargement of 4th ventricle.
|
|
|
Aortic arch derivatives
1st, 2nd, 3rd, 4th, 6th |
1st=MAXillary a
2nd=Stapedial a, hyoid a 3rd=common carotid, prox int carotid 4th=prox R subclavian, part of aortic arch 6th=L pulm artery and ductus |
|
|
How do we describe the parts of the branchial/pharyngeal apparatus? What do they correspond to (ecto/meso/endo)?
|
"CAP covers from out to in."
Cleft-ectoderm Arch-mesoderm Pouch-endoderm |
|
|
What are the branchial cleft derivatives?
|
1st= ext auditory meatus
2-4=temporary cervical sinuses that are OBLITERATED by 2nd arch mesenchyme |
|
|
What is a persistent cervical sinus?
|
Branchial cleft cyst in lateral neck.
|
|
|
Branchial arch 1: cartilage/bones, muscles, nerves?
|
JAW
Cartilage/bones: Mandible, sphenomandibular lig, malleus, incus. Muscles: Mastication, mylohyoid, ant belly digastric, tensor tympani, tensor veli palatini, ant 2/3 tongue Nerves: CN V2/V3 |
|
|
Branchial arch 2: cartilage/bone, muscles, nerves?
|
FACE
Cartilage: stapes, styloid process, lesser horn hyoid, stylohyoid lig Muscles: facial expression, stapedius, stylohyoid, post belly digastric Nerves: CN7 |
|
|
Branchial arch 3: cartilage, muscles, nerves?
|
TONGUE
Cartilage: greater horn hyoid Muscles: stylopharyngeus Nerve: CN9 |
|
|
Branchial arch 4-6: cartilage/bones, muscles, nerves?
|
LARYNX
Cartilage/bones: thyroid, cricoid, arytenoids, corniculate, cuneiform Muscles: pharyngeal constrictor, cricothyroid, levator veli palatini (4th), and all intrinsic muscles larynx except crico (6th) Nerves: CN10 - sup laryngeal nerve (4th) and recurrent laryngeal nerve (6th) **crico innervated by ext branch of superior laryngeal n., all others by recurrent laryngeal n. |
|
|
What is the embryologic abnl in Treacher-Collins?
|
Failure of 1st arch neural crest cells to migrate, causing mandibular hypoplasia, facial abnl
|
|
|
What is congenital pharyngocutaenous fistula?
|
Failure of 3rd arch, hole from tonsils to lat neck
|
|
|
What part of the tongue do the 3rd and 4th arch contribute to?
|
Post 1/3 of tongue
|
|
|
1st branchial pouch?
|
Middle ear, eustachian tube, mastoid air cells
|
|
|
2nd branchial pouch?
|
epithelial lining of palatine tonsils
|
|
|
3rd branchial pouch (dorsal and ventral wings)?
|
dorsal wings - inferior parathyroids (parathyroids sit behind)
ventral wings - thymus |
|
|
4th branchial pouch?
|
superior parathyroids
|
|
|
What is embryologic origin of Di-George Syndrome?
|
Abberant development of 3rd and 4th branchial pouch.
-Thymic aplasia (T cell def) -Parathyroid hypoplasia (hypoCa) 22q11 deletion |
|
|
What parts of the branchial apparatus make up the tongue? What nerves are responsible for sensation and taste in each part?
|
Ant 2/3= arch1, sensation CNV3, taste CN7
Post 1/3- arch 3/4, sensation CN9/10, taste CN9/10. |
|
|
Where is the most common site of ectopic thyroid tissue?
|
Tongue (duh!)
|
|
|
How do you get a cleft lip?
|
failure of fusion maxillary and medial nasal processes (primary palate)
|
|
|
How do you get a cleft palate?
|
failure of fusion lat palatine processes, nasal septum, and/or med palatine process (secondary palate)
|
|
|
Failure of ant abd wall to close...
Rostral? Lateral? Caudal? |
Rostral - sternal defect
Lat - gastroschisis, omphalocele Caudal - bladder extrophy |
|
|
What is the cause of jejunal, ileal, or colonic atresia?
|
vascular accident
|
|
|
Most common type of TEF?
|
Blind esophagus, connection of lower eso to trachea. Cyanosis, choking, vomiting with feeding.
|
|
|
What causes congenital pyloric stenosis?
|
Hypertrophy of the pylorus
|
|
|
What structure does pancreas come from?
What do the dorsal and ventral buds become? |
Derived from foregut.
Ventral - uncinate process Dorsal+ventral - head, main duct Dorsal - everything else |
|
|
What causes annular pancreas?
Pancreas divisum? |
-ventral bud wraps around duo
-ventral and dorsal buds fail to fuse at 8 wks |
|
|
Where does spleen arise from?
|
Arises from dorsal mesentery (mesodermal) but supplied by artery of foregut (splenic)
|
|
|
Explain development of the kidney?
|
Pronephros degen week 4. Mesonephros interim kidney till week 12, gives off ureteric bud which stimulates metanephros to differentiate into glom and tubules. Metanephros permanent. Ureteric bud becomes ureter, pelvis, calyces, collecting tubules.
|
|
|
What structures does the ureteric bud become? Where does it originate from?
|
Ureter, pelvis, calyces, collecting tubules. Also stimulate metanephros to differentiate into Bowman's, glomerulus, PCT, tDLH, TALH, DCT.
Originates from mesonephros. |
|
|
Why is the ureteropelvic jxn the most common site of obstruction in the fetus (hydronephrosis)?
|
UPJ is last to canalized!
|
|
|
What is Potter's Syndrome? What is the cause?
|
Malformation of the ureteric bud. Renal agenesis then leads to oligohydramnios, pulm hypoplasia, and limb deformities.
|
|
|
Where do horseshoe kidneys get trapped as they ascend from pelvis into abd?
|
under IMA
|
|
|
What is the default pathway for genital embryology?
|
Female. Mesonephros involutes, paramesonephros develops.
|
|
|
How do you become male?
|
1. SRY gene codes for TDF-->testes
2. MIF secreted by Sertoli cells makes Mullerian structures involute. 3. Androgens from Leydig cells stimulate mesonephric ducts. |
|
|
Mesonephric/Wolffian duct develops into what structures?
|
Epididymis, vas deferens, seminal vesicles ejaculatory duct
**NOT the prostate! That comes from UG sinus. |
|
|
Paramesonephric/Mullerian duct develops into what structures?
|
Fallopian tubes, uterus, upper 1/3 of vagina
|
|
|
How do you get a bicornuate uterus?
|
Incomplete fusion of paramesonephric ducts.
|
|
|
What causes hypospadias?
|
Failure of urethral folds to close (ventral shaft)
|
|
|
What causes epispadias? What is assoc?
|
Faulty positioning of genital tubercle, assoc with bladder Extrophy
|
|
|
Genital tubercle
|
Glans penis/clitoris
Corpus cavernosum and spongiosum/vestibular bulbs |
|
|
UG sinus
|
Bulbourethral glands/greater vestibular glands (bartholin)
Prostate/urethral and paraurethral glands (skene) |
|
|
UG folds
|
Ventral shaft of penis/labia minora
|
|
|
Labioscrotal swelling
|
Scrotum/labia majora
|
