Embryology Flashcards
what are the complications of therapeutic supplemental O2 during neonatal respiratory distress syndrome
Retinopathy
Intraventricular hemorrhage
Bronchopulmonary dysplasia
due to free radicals
club cells in lung
nonciliated
secrete component to surfactant
degrade toxins
reserve
bronchogenic cysts
abnormal budding of foregut and dilatation of terminal or large bronchi
discrete round air-filled densities on CXR
can cause infection
5 stages to lung development
1) Embryonic (weeks 4-7)- trachea, bronchi
2) Pseudoglandular (5-16)- terminal bronchioles
3) Canalicular (16-26)- resp bronchioles and alveolar ducts
4) Saccular (26-birth)- alveolar terminal sacs, pneumocytes
5) Alveolar (32- 8 years)- adult alveoli (secondary septation)
mnemonic: Emily Pogrund Can’t Sex Anyone
sonic hedgehog gene produced where
base of limbs in zone of polarizing activity
sonic hedgehog mutation leads to…
holoprosencephaly
Wnt 7 gene and FGF gene produced where
apical ectodermal ridge of each limb
FGF gene function
stimulates mitosis of mesoderm– lengthens limbs
Hox mutations
appendages in wrong locations
when does hcg secretion begin
day 6- blastocyst implantation
what happens week 2 and 3?
2- 2 layers- epiblast, hypoblast
3- 3 layers- endoderm, mesoderm, ectoderm
what happens week 4
4 limbs- form
4 chambers- heart beats
when is heartbeat detected by ultrasound
week 6
when do fetal movements begin
week 8
when can you decipher genitalia
week 10
when are teratogens most suscpetible to causing injury
week 3-8 (embryonic period)- organogenesis
before week 3- all or none
after week 8- growth function affected
at what stages for MZ twins can you get dichorionic, diamnionic; monochor, diamnio; mono, mono; conjoined
separating at…
di, di: 0-4 days
monochorionic, diamnionic: 4-8 days
mono, mono: 8-12 days
conjoined- after 13 days
patent urachus
failure of urachus to obliterate–> urine leaks from umbilicus
urachal cyst
partial failure of urachus to obliterate–> cyst
–> adenocarc, infection
vesicourachal diverticulum
slight failure of urachus to obliterate –> bladder outpouching
vitelline duct
connects yolk sac to midgut lumen
closes 7th week
vitelline fistula
vitelline duct completely fails to close (unlike meckel which is partial)
–> meconium discharge from umbilicus
aoritc arches
1- maxillary artery
2- stapedial and hyoid artery
3- common carotid, internal carotid
4- aortic arch (left), right subclavian
6- pulm arteries and ductus arteriosus
branchial (pharyngeal) apparatus
composed of:
clefts- ectoderm
arches- mesoderm
pouches- endoderm
branchial clefts
1- external auditory meatus
2-4 temporary cervical sinus
If this persists–> branchial cleft cyst anterior to SCM (immobile during swallowing unlike thryglossal cyst)
branchial arch 1
Maxilla, zygomatic bone, mandible, meckel cartilage, malleus, incus, sphenoManidibular ligament
Muscles of Mastication, Mylohyoid, anterior belly of digastric, tensor tympani, tensor veli palatini
Cn V2 and V3
branchial arch 2
Reichert cartilage- stapes, styloid, stylohyoid lig
stapedius, stylohyoid, platySma, posterior belly of digastric
CN VII
pierre robin sequence
abnl branchial arch 1 and 2
micrognathia, glossoptosis, cleft palate, airway obstruction
treacher collins syndrome
neural crest dysfunction – abnl branchial arch 1 and 2
manidble hypoplasia
facial abnl
branchial arch 3
greater horn of hyoid
stylopharnygeus
CN IX
branchial arch 4-6
arytenoids, cricoid, corniculate, cuneiform, thryoid
4: pharyngeal constrictors, cricothyroid, levator veli palatini, CN X (superior laryngeal)
6: intrinsic muscles of larynx except cricothyroid CN X (recurrent laryngeal)
what branchial arches make up anterior and posterior tongue
anterior: 1-2
posterior: 3-4
branchial pouch 1
middle ear, eustachian, mastoid air
branchial pouch 2
palatine tonsils
branchial pouch 3
dorsal- inferior parathyroids
ventral- thymus
branchial 4th pouch
dorsal–> superior parathyroids
ventral: C cells of thyroid, ultimobranchial body
mneumonic for pouches
ear, tonsils, bottom to top
septate uterus
incomplete resorption of septum
decrease fertility
bicorunate uterus
incomplete fusion of mullerian ducts
risk of complicated pregnancy
uterus didelphys
complete fusion failure
double uterus, cervix, vagina
pregnancy is possible!
