Embryology

Vitelline duct: closure time

VItelline duct normally closes around week VI of intrauterine life.

Potter syndrome: features

POTTER

• Pulmonary hypoplasia
• Oligohydrominios
• Twisted skin (wrinkly skin)
• Twisted face (Potter facies)
• Extremities defects
• Renal agenesis (bilateral)

 

Placenta-crossing substances

“WANT My Hot Dog”

• Wastes
• Antibodies
• Nutrients
• Teratogens
• Microorganisms
• Hormones/ HIV
• Drugs

 

Cranial and spinal neural crest: major derivatives

GAMES

• Glial cells (of peripheral ganglia)
• Arachnoid (and pia)
• Melanocytes
• Enteric ganglia
• Schwann cells

 

Mesoderm components

MESODERM

• Mesothelium (peritoneal, pleural, pericardial)/ Muscle (striated, smooth, cardiac)
• Embryologic Spleen/ Soft tissue/ Serous linings/ Sarcoma/ Somite
• Osseous tissue/ Outer layer of suprarenal gland (cortex)/ Ovaries
• Dura/ Ducts of genitalia
• Endothelium
• Renal Microglia
• Mesenchyme/ Male gonad

 

Vasculogenesis vs. angiogenesis

“Vascu is new. Angi is pre“: Vasculogenesis is new vessels developing in situ from existing mesenchyme. Angiogenesis is vessels develop from sprouting off pre-existing arteries.

Weeks 2, 3, 4 of development: an event for each

• Week Two: Bilaminar germ disc.
• Week Three: Trilaminar germ disc.
• Week Four: Four limbs appear.

 

Teratogenesis: when it occurs

TEratogenesis is most likely during organogenesis–between the: Third and  Eighth weeks of gestation.

 

Tetrology of Fallot

“Don’t DROP the baby”

• Defect (VSD)
• Right ventricular hypertrophy
• Overriding aorta
• Pulmonary stenosis

 

Lung development phases

“Every Premature Child Takes Air”

• Embryonic period
• Pseudoglandular period
• Canalicular peroid
• Terminal sac period
• Alveolar period

Branchial arch giving rise to aorta

“Aor– from Four“: Aorta is from fourth arch.

 

Neuroectoderm derivatives

Neuroectoderm gives rise to:

• Neurons
• Neuroglia
• Neurohypophysis
• piNeurol (pineal) gland

 

Tetrology of Fallot

“IHOP-International House of Pancakes”:

• Interventricular septal defect
• Hypotrophy of right ventricle
• Overriding aorta
• Pulmonary stenosis

 

Woffian duct (mesonephric duct) derivatives

Gardener’s SEED:

Female: Gartner’s duct, cyst

Male:

• Seminal vesicles
• Epididymis
• Ejaculatory duct
• Ductus deferens

 

Foregut derivatives

“Little Embryo People Do Like Swallowing, Producing Gas”: Lungs Esophagus Pancreas Duodenum (proximal) Liver Stomach Pancreas Gall bladder

 

 You can suggest more mnemonics …

Warm regards,

Dr. Indrajit Rana