Embryo 2

Front 1

Sonic Hedgehog Gene

Back 1

Produced in zone of polarizing acitivty and is responsible for anterior-posterior axis

Front 2

Wnt-7 gene

Back 2

Produced at apeical ectodermal ridge and necessary for dorsal-ventral axis organization

Front 3

FGF Gene

Back 3

Produced at apical ectodermal ridge and stimulates mitosis of underlying mesoderm - limb lengthening

Front 4

Homeobox Gene

Back 4

Segmental organization of embryo in craino-caudal direction

Front 5

Fetal landmarks Day 0

Back 5

Fertilation by sperm - zygote formation

Front 6

Fetal Landmarks within week 1

Back 6

hCG secretion after blastocyst implantation

Front 7

Fetal Landmarks within week 2

Back 7

Bilaaminar disk comprised of epiblast and hypoblast

Front 8

Fetal Landmarks within week 3

Back 8

Gastrulation. Formation of primitive streak, notochord, and neural plate

Front 9

Fetal Landmarks weeks 3-8

Back 9

Neural tube formed by neuroectoderm. Closure of neural tube by week 4.
Organogenesis
Period of susceptibility to teratogens

Front 10

Fetal Landmarks week 4

Back 10

Heart beat
Upper and lower limb buds

Front 11

Fetal Landmarks within week 8

Back 11

movement
fetus looks like baby (fetal period)

Front 12

Fetal Landmarks week 10

Back 12

genitalia have male or female characteristics

Front 13

Neural Development

Back 13

- Notochord induces ectoderm to form neuroectoderm and neural plate
- Neural plate gives rise to neural tube and neural crest
- Notochord becomes nucleus pulposus (part of intervertebral disk in adults)

Front 14

Fetal Spinal Cord

Back 14

Fetal spinal cord
Alar - dorsal - Sensory
Basal - ventral - Motor

Front 15

Rule of 2's

Back 15

2nd week
2 germ layers (epiblast, hypoblast): bilaminar disk
2 cavities (amniotic cavity, yolk sac)
2 placental parts (cytotrophoblast, syncytiotrophoblast)

epiblast - ectoderm precursor, invaginates to form primitive streak, which gives rise to intraembryonic mesoderm and part of endoderm

Front 16

Rule of 3's

Back 16

3rd week
3 germ layers (ecto, meso, endo): gastrula

Front 17

Rule of 4s

Back 17

4th week
4 heart chambers
4 limb buds grow

Front 18

Surface ectoderm derivatives

Back 18

Adenohypophysis (from Rathke's pouch), sensory organs of ear, lens, oral and olfactory epithelium, epidermis, salivary/sweat/mammary glands

Front 19

3 types of ectoderm derivatives

Back 19

Surface ectoderm
Neuroectoderm
Neural crest

Front 20

Endoderm Derivatives

Back 20

Gut tube epithelium (lungs, liver, pancreas, thymus, parathyroid, thyroid follicular cells

Front 21

Neuroectoderm derivatives

Back 21

Brain (CNS and neurohypophysis), retina, spinal cord

Front 22

Mesoderm Derivatives

Back 22

Muscle, bone, CT, serosas, spleen, CV, lymph, blood, bladder, urethra, vagina, eustachian tube, kidneys, adrenal cortex, dermis, testis, ovaries

Front 23

Neural crest derivatives

Back 23

ANS, PNS ( dorsal root ganglia, CNs, celiac ganglion), melanocytes, chromaffin cells of adrenal medulla, parafollicular C cells of thyroid, bones of skull, odontoblasts (Odonto-Crest toothpaste), aorticopulmonary septum

Front 24

Malformation

Back 24

Malformation - intrinsic disruption (week 3-8)

Front 25

Deformation

Back 25

Extrinsic disruption (after week 8)

Front 26

Agenesis

Back 26

Absent organ due to absent primordial tissue

Front 27

Hypoplasia

Back 27

Incomplete organ development in presence of primordial tissue

Front 28

Aplasia

Back 28

Absent organ in presence of primordial tissue

Front 29

VACTERL Association

Back 29

Mesoderm defects

Vertebral, Anal atresia, Cardiac, Tracheo-Esophageal fistula, Renal, Limb

Front 30

Craniopharyngioma

Back 30

Benign Rathke's pouch tumor w/ cholesterol crystals and calcifications

Front 31

Teratogen effects:
Before week 3
Weeks 3-8
After week 8

Back 31

Before week 3: all-or-none effect
Weeks 3-8: most susceptible
After week 8: growth and function affected

Front 32

Teratogen effects:
ACE Inhibitors

Back 32

Renal damage

Front 33

Teratogen effects:
Alcohol

Back 33

Fetal alcohol syndrome
Leading cause of birth defects and mental retardation

Front 34

Teratogen effects:
Alkylating agents

Back 34

Absence of digits, multiple anomalies

Front 35

Teratogen effects:
Aminoglycosides

Back 35

CN VIII toxicity (also cause ototoxicity, as well as nephrotoxicity, in adults)

Front 36

Teratogen effects:
Cocaine

Back 36

Abnormal fetal dev't and fetal addiction
Placental abruption
Spontaneous abortion
IUGR

Front 37

Teratogen effects:
Diethylstilbestrol (DES)

Back 37

Vaginal clear cell adenocarcinoma

Front 38

Teratogen effects:
Folate antagonists

Back 38

NTDs

Front 39

Teratogen effects:
Iodide (lack or excess)

Back 39

Congenital goiter or hypothyroidism

Front 40

Teratogen effects:
Lithium

Back 40

Ebstein's anomaly (atrialized RV)

Front 41

Teratogen effects:
Maternal diabetes

Back 41

Caudal regression syndrome (ranges from anal atresia to sirenomelia: fused legs; agenesis of sacrum --> flaccid paralysis of legs and urinary incontinence)

Macrosomia

Front 42

Teratogen effects:
Smoking (nicotine, CO)

Back 42

Preterm labor
Placental problems
IUGR
ADHD

Front 43

Teratogen effects:
Tetracyclines

Back 43

Discolored teeth
Bone growth retardation

Front 44

Teratogen effects:
Thalidomide

Back 44

Limb defects ("flipper limbs")

Front 45

Teratogen effects:
Valproate and carbamazepine

Back 45

Inhibition of intestinal folate absorption --> NTDs

Front 46

Teratogen effects:
Vitamin A excess

Back 46

V. high risk for spontaneous abortions and birth defects (cleft palate, cardiac abnormalities, CNS defects)

Front 47

Teratogen effects:
Warfarin

Back 47

Bone deformities
Fetal hemorrhage
Abortion

Front 48

Teratogen effects:
X-rays and anticonvulsants

Back 48

Multiple anomalies

Front 49

Teratogen effects:
Marijuana

Back 49

Low birth weight

Front 50

Teratogen effects:
Aspirin

Back 50

Bleeding

Front 51

There are ___ umbilical arteries and __ umbilical veins

Back 51

2
1

Front 52

Single umbilical artery is associated with

Back 52

Congenital and chromosomal anomalies

Front 53

Umbilical arteries and veins are derived from?

Back 53

Allantois, which becomes urachus at 3rd week (duct btwn bladder and yolk sac)

Front 54

Failure of urachus to obliterate causes these two abnormalities

Back 54

Patent urachus
Vesicourachal diverticulum

Front 55

Patent urachus

Back 55

Urine discharge from umbilicus

Front 56

Vesicourachal diverticulum

Back 56

Outpuching of bladder

Front 57

Another word for the vitelline duct

Back 57

Omphalomesenteric duct

Front 58

Function of vitelline duct

Back 58

Connects yolk sac to midgut lumen; obliterated at 7th wk

Front 59

2 vitelline duct abnormalities

Back 59

Vitelline fistula
Meckel's diverticulum

Front 60

Vitelline fistula

Back 60

Failure of duct to close --> meconium discharge from umbilicus

Front 61

Meckel's diverticulum

Back 61

Partial closure of vitelline duct, with patent portion attached to ileum

May have ectopic gastric mucosa --> melena and periumbilical pain

Front 62

3 types of embryological veins and their fates

Back 62

Umbilical --> degenerate
Vitelline --> veins of portal system
Cardinal --> veins of systemic circulation (drain into sinus venosus in utero)

Front 63

Truncus arteriosus -->

Back 63

Ascending aorta and pulmonary trunk (split by neural crest migration)

Front 64

Failure of neural crest migration to split the truncus arteriosus leads to these 3 cyanotic congenital heart diseases

Back 64

Transposition
ToF
Persistent TA

Front 65

Bulbus cordis -->

Back 65

RV and smooth parts of L and R ventricle

Front 66

Primitive ventricle -->

Back 66

Trabeculated parts of L & R ventricle

Front 67

Primitive atria -->

Back 67

Trabeculated L and R atria

Front 68

L horn of sinus venosus

Back 68

Coronary sinus

Front 69

R horn of sinuus venosus

Back 69

Smooth part of RA

Front 70

R common cardinal vein and R anterior cardinal vein

Back 70

SVC

Front 71

Endocardial cushion defects -->

Back 71

AV septum defects (membranous septal defect)

Front 72

Is the foramen ovale in septum primum or secundum?

Back 72

Septum secundum

Front 73

Cause of patent foramen ovale

Back 73

Excessive resorption of septum primum and/or secundum

Front 74

4 sites of fetal erythropoiesis

Back 74

Young Liver Synthesizes Blood

Yolk sac (3-8wks)
Liver (6-20wks)
Spleen (9-28 wks)
BM (29 wks onward)

Front 75

Ductus venosus

Back 75

Umbilical vein --> IVC (bypassing hepatic circulation

Front 76

Foramen ovale

Back 76

IVC --> aorta (bypassing lungs)

Front 77

Ductus arteriosus

Back 77

Pulmonary artery --> aorta (bypassing lungs)

Front 78

Why does the foramen ovale close at birth

Back 78

Decreased resistance in pulmonary resistance with first breath: LAP > RAP

Front 79

Name for foramen ovale after it is closed?

Back 79

Fossa ovalis

Front 80

3 brain primitive structures

Back 80

Prosencephalon, mesencephalon, rhombencephalon

Front 81

Derivatives of prosencephalon

Back 81

Prose tells of someone dying
Telencephalon --> cerebral hemispheres
Diencephalon --> thalami

Front 82

Mesencephalon

Back 82

Metencephalon --> mibrain

Front 83

Rhombencephalon

Back 83

Rhombus needs a meter to measure its miles

Metencephalon--> pons, cerebellum
Myelencephalon --> medulla

Front 84

Elevated AFP and acetylcholinesterase in CSF indicate

Back 84

Neural tube defect

Front 85

Holoprosencephaly is associated with these three things

Back 85

Patau's Syndrome
Severe fetal alcohol syndrome
Cleft lip/ palate

Front 86

Chiari II

Back 86

Cerebellar tonsillar herniation
Presents w/ syringomyelia, thoracolumbar myelomeningocele

Front 87

Dandy-Walker

Back 87

Large posterior fossa; absent cerebellar vermis w/ cystic enlargement of 4th ventricle

Can lead to hydrocephalus and spina bifida

Front 88

Branchial clefts, arches, and pouches are derived from which -derms?

Back 88

Clefts: ectoderm
Arches: mesoderm
Pouches: endoderm

Front 89

1st branchial cleft develops into

Back 89

External auditory meatus

Front 90

2nd thru 4th clefts form _____, which are obliterated

Back 90

Temporary cervical sinuses

Front 91

Persistent cervical sinus -->

Back 91

Branchial cleft cyst w/in lateral neck

Front 92

Branchial Arch 1: M
Cartilage, Muscles, and Nerves

Back 92

Meckel's cartilage (mandible, malleus, incus, sphenoMandibular ligament)

Mastication muscles, mylohyoid

CN V2 and V3

Front 93

Branchial Arch 2: S
Cartilage, Muscles, and Nerves

Back 93

Reicher's cartilage: Stapes, Styloid process, less horn of hyoid, Stylohyoid ligament

Muscles of facial expression, Stapedius, Stylohyoid

CN VII

Front 94

Branchial Arch 3: Pharyng
Cartilage, Muscles, and Nerves

Back 94

Greater horn of hyoid
Stylopharngeus
CN IX (glossopharyngeal)

Front 95

Branchial Arch 4-6
Cartilage, Muscles, and Nerves

Back 95

Cartilages: thyroid, cricoid, arytenoids ,corniculate, cuneiform

4th arch is cricothyroid, 6th arch is all intrinsic muscles of larynx except cricothyroid

CN X (4th arch: swallowing form superior laryngeal branch, 6th arch: speaking from recurrent laryngeal branch)

Front 96

1st branchial pouch

Back 96

Endoderm-lined structures of ear

Front 97

2nd branchial pouch

Back 97

Epithelial lining of palatine tonsil

Front 98

3rd branchial pouch

Back 98

Inferior parathyroids and thymus (3rd pouch structures end up below 4th opuch structures)

Front 99

4th branchial pouch

Back 99

Superior parathyroids

Front 100

Tongue development involves which branchial arches?

Back 100

Anterior 2/3: 1st arch
Posterior 1/3: 3rd and 4th arches

Front 101

Pyramidal lobe of thyroid, if it exists, is a persistent?

Back 101

Thyroglossal duct (connects thyroid diverticulum to tongue)

Front 102

Foramen cecum is remnant of

Back 102

Thyroglossal duct

Front 103

Most common ectopic thyroid tissue site?

Back 103

Tongue

Front 104

How to differentiate thyroglossal duct cyst from branchial cleft cyst

Back 104

Thryoglassal: midline, moves with swallowing
Branchial cleft (from persistent cervical sinus): lateral neck, stationary with swallowing

Front 105

When does a lingual thyroid occur

Back 105

If thyroid falls to migrate downward

Front 106

Potential complication of removal of lingual thyroid?

Back 106

Hypothyroidism if is only thyroid tissue

Front 107

Cleft lip

Back 107

M&Ms

Failure of fusion of maxillary and medial nasal process

Front 108

Cleft palate

Back 108

Palatine

Failure of fusion of lateral palatine process, nasal septum, and/or medial palatine process

Front 109

Foregut, midgut, and hindgut
Midgut consists of?

Back 109

Duodenum to transverse colon

Front 110

What causes jejunal, ileal, or colonic atresia?

Back 110

Vascular accident (apple peel atresia)

Front 111

Normal midgut development

Back 111

Herniates thru umbilical ring, then returns and rotates around SMA

Front 112

Pathology of midgut development

Back 112

Malrotation of midgut, omphalocele, intestinal atresia or stenosis, volvulus

Front 113

Gastroschisis

Back 113

Extrusion of abdominal contents thru abdominal folds

Front 114

Omphalocele

Back 114

Persistence of herniation of abdominal contents into umbilical cord

Front 115

How to distinguish gastroschisis from omphalocele

Back 115

Gastroschisis: not covered by peritoneum, often not midline

Omphalocele: covered by peritoneum, midline

Front 116

Palpable "olive" mass in epigastric region + nonbilious projectile vomiting at 2wks in first born male

Back 116

Congenital pyloric stenosis (from hypertrophy of pylorus --> obstruction)

Front 117

Dorsal and ventral pancreatic buds -->

Back 117

Pancreatic head
Main pancreatic duct

Front 118

Ventral pancreatic bud -->

Back 118

Uncinate process

Front 119

Dorsal pancreatic body -->

Back 119

Everything else

Front 120

Annular pancreas

Back 120

Ventral bud abnormally encircles duodenum: ring of pancreatic tissue may cause narrowing --> recurrent bilous vomiting

Front 121

Pancreas divisum

Back 121

Ventral and dorsal parts fail to fuse (2 ducts open into duodenum)
Usually clinically silent; may predispose to pancreatitis

Front 122

Spleen: mesoderm or endoderm?

Back 122

Mesoderm, but supplied by celiac artery (of foregut)

Front 123

3 stages of kidney embryology

Back 123

Pronephros --> mesonephros --> metanephros

Front 124

Ureteric bud -->

Back 124

Ureter, pelvises, calyces/ collecting ducts

Front 125

Metanephric mesencyme -->

Back 125

Glomerulus, renal tubules

Front 126

Most common site of renal obstruction (hydronephrosis) in fetus?

Back 126

Ureteropelvic junction with kidney (last to canalize)

Front 127

Bilateral renal agenesis leads to

Back 127

Potter's Syndrome

Front 128

3 sequelae of Potter's Syndrome

Back 128

Limb deformities, facial deformities, pulmonary hypoplasia (respiratory failure w/in hours)

Front 129

Cause of Potter's Syndrome

Back 129

Malformation of ureteric bud

Front 130

Horseshoe kidney

Back 130

Inferior poles of both kidneys fuse

Front 131

Complications of horseshoe kidney

Back 131

Normal function, but can lead to urinary tract obstruction/ hydronephrosis

Front 132

Cells that secrete Mullerian inhibitory factor

Back 132

Sertoli: suppresses development of paramesonephric ducts

Front 133

What stimulates development of mesonephric ducts?

Back 133

Increased andorgens from Leydig cells

Front 134

Another name for mesonephric duct

Back 134

Wollfian

Front 135

Another name for paramesonephric duct?

Back 135

Mullerian

Front 136

Which male internal structure is not derived from the Wolffian duct?

Back 136

Pancreas (is from urogenital sinus)

Front 137

Incomplete fusion of paramesonephric ducts -->

Back 137

Bicornuate uterus

Front 138

Which is more common, hypospadius or epispadius?

Back 138

Hypospadias

Front 139

Hypospadias can predispose to

Back 139

UTIs

Front 140

Epispadias is associated with

Back 140

Exstrophy of bladder

Front 141

What causes hypospadias?

Back 141

Failure of urethral folds to close

Front 142

What causes epispadias?

Back 142

Faulty positioning of genital tubercle

Front 143

Consequence of failutre of obliteration of processus vaginalis (normall forms tunica vaginalis)

Back 143

Connection between scrotum and peritoneal cavity:
If small --> hydrocele
If large --> indirect inguinal hernia

Front 144

Genital tubercle -->

Back 144

Glans penis and glans clitoris
Corpus c/s and vestibular bulbs

Front 145

URogenital sinus -->

Back 145

Glands

Front 146

Urogenital folds -->

Back 146

Ventral shaft of penis (penile urethra) and labia minora

Front 147

Labioscrotal swelling -->

Back 147

Scrotum and labia majora