One Word_Embryology Flashcards Preview

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Flashcards in One Word_Embryology Deck (51):
1

Wnt-7 gene

Produced at apical ectodermal ridge (thickened ectoderm at distal end of each developinf limb). Necessary for proper organization along dorsal-ventral axis.

2

Treacher Collins syndrome

1st-arch neural crest fails to migrate → mandibular hypoplasia, facial abnormalities

3

Teratogens: X-rays, anticonvulsants

Multiple anomalies

4

Teratogens: Warfarin

Bone deformaties, fetal hemorrhage, abortion

5

Teratogens: Vitamin A (excess)

Extremely high risk for spontaneous abortions and birth defects (cleft palate, cardiac abnormalities)

6

Teratogens: Valproate

Inhibition of intestinal folate absorption → Neural tube defects

7

Teratogens: Thalidomide

Limb defects ("flipper" limbs)

8

Teratogens: Tetracyclines

Discolored teeth

9

Teratogens: Smoking (nicotine, CO)

Preterm labor, placental problems, IUGR, ADHD

10

Teratogens: Maternal diabetes

Caudal regression syndrome (anal atresia to sirenomelia)

11

Teratogens: Lithium

Ebstein's anomaly (atrialized right ventricle)

12

Teratogens: Iodide (lack or excess)

Congenital goiter or hypothyroidism

13

Teratogens: Folate antagonists

Neurol tube defects

14

Teratogens: Diethylstilbestrol (DES)

Vaginal clear cell adenocarcinoma

15

Teratogens: Cocaine

Abnormal fetal development and fetal addiction; placental abruption

16

Teratogens: Aminoglycosides

CN VIII toxicity

17

Teratogens: Alkylating agents

Absence of digits, multiple anomalies

18

Teratogens: Alcohol

Leading cause of birth defects and mental retardation; fetal alcohol syndrome

19

Teratogens: ACE inhibitors

Renal damage

20

Sonic hedgehog gene

Produced at base of limbs in zone of polarizing activity. Involved in patterning along anterior-posterior axis.

21

Homeobox gene

Involved in segmental organization or embryo in a craniocaudal direction

22

FGF gene

Produced at apical ectodermal ridge. Stimulates mitosis of underlying mesoderm, providing for lengthening of limbs.

23

Embryology: What is associated with Epispadias?

Exstrophy of the bladder

24

Embryology: Vitelline duct

7th week, obliteration of vitelline duct (omphalomesenteric duct), which connects yolk sac to midgut lumen.

25

Embryology: Uteropelvic junction with kidneys

last to canalize → most common site of obstruction (hydronephrosis) in fetus

26

Embryology: Urachal duct

3rd week, yolk sac forms allantois, later becomes urachus, a duct between bladder and yolk sac.

27

Embryology: Truncus arteriosus pathology

Failure neural crest migration: ①Transposition of great vessels (failure to spiral); ②Tetralogy of Fallot (skewed AP septum development); ③Persistent TA (partial AP septum development)

28

Embryology: Truncus arteriosus

Ascending aorta and pulmonary trunk

29

Embryology: Syncotiotrophoblast

outer layer of chorionic villi; secretes hCG (structurally similar to LH; stimulates corpus luteum to secrete progesterone during first trimester)

30

Embryology: Patent foramen ovale

Abnormal interatrial septum development caused by excessive resorption of septum primum and/or secundum

31

Embryology: Omphalocele

persistence of herniation of abdominal contents into umbilical cord, covered by peritoneum

32

Embryology: Jejunal, ileal, colonic atresia

Due to vascular accident (apple peel atresia)

33

Embryology: Hypospadias

abnormal opening of the penile urethra on inferior (ventral) side of penis due to failure of urethral folds to close

34

Embryology: Holoprosencephaly

↓seperation of hemispheres across midline; results in cyclopia; associated with Patau's syndrome, severe fetal alcohol syndrome, and cleft lip/palate.

35

Embryology: Gastroschisis

extrusion of abdominal contents through abdominal folds; not covered by peritoneum

36

Embryology: Epispadias

abnormal opening of penile urethra on superior (dorsal) side of penis due to faulty positioning of genital tubercle

37

Embryology: Duodenal atresia

Failure to recanalize (trisomy 21)

38

Embryology: Decidua basalis

Maternal component, derived from the endometrium. Maternal blood in lacunae.

39

Embryology: Dandy-Walker syndrome

large posterior fossa; absent cerebellar vermis with cystic enlargement of 4th ventricle. Can lead to hydrocephalus and spina bifida.

40

Embryology: Cytotrophoblast

inner layer of chorionic villi. Cyto makes cells.

41

Embryology: Cricothyroid

Only larynx muscle innervated by the superior laryngeal branch

42

Embryology: Bulbus cordis

Right ventricle and smooth parts (outflow tract) of left and right ventricle

43

Embryology: Arnold chiari II

cerebellar tonsillar herniation through foramen magnum with aqueductal stenosis and hydrocephaly. Often presents with syringomyelia, thoraco-lumbar myelomeningocele.

44

Embryology: Anencephaly

Malformation of anterior end of neural tube; no brain/calvarium, elevated AFP, polyhydramnios (no swallowing center in brain).

45

Descent of testes and ovaries: Processus vaginalis (evagination of peritoneum)

Female remnant: Obliterated Male remnant: Forms tunica vaginalis

46

Descent of testes and ovaries: Gubernaculum (band of fibrous tissue)

Female remnant: Ovarian ligament + round ligament of uterus Male remnant: Anchors testes within scrotum

47

Congenital pharyngocutaneous fistula

persistence of cleft and pouch → fistula between tonsillar area, cleft in lateral neck

48

Branchial cleft derivatives

1st cleft - external auditory meatus 2nd - 4th clefts - form temporary cervical sinuses, which are obliterated by proliferation of 2nd arch mesenchyme Persistent cervical sinus → branchial cleft cyst within lateral neck

49

Basal plate

Ventral, motor

50

Aortic arch derivatives

1st-part of Maxillary artery (branch of external carotid) 2nd-Stapedial artery and hyoid artery 3rd-common Carotid artery and proximal part of internal carotid artery 4th-on left, aortic arch; on right, proximal part of right subclavian artery 6th-proximal part of pulmonary arteries and (on left only) ductus arteriosus

51

Alar plate

Dorsal, sensory