During the third week of development, the blastocyst undergoes a variety of differentiation processes responsible for the formation of the gastrula and, eventually, the embryo. This differentiation creates cell lineages that eventually become a variety of body systems. What cell lineage, present at this date, is responsible for the formation of the liver?
ANeuroectoderm
BSyncytiotrophoblasts
CEctoderm
DEndoderm
EMesoderm
A 31-year-old man presents for his annual physical exam. The physician fails to palpate a ductus deferens on the left side. An ultrasound confirms absence of the left ductus deferens and further reveals absence of the left epididymis, seminal vesicle, and kidney. Spermogram and reproductive hormones panel are within normal limits. Left-sided agenesis of an embryonic anlage is suspected. Which two structures are connected by this anlage during embryogenesis?
AMetanephros and coelom
BMesonephros and coelom
CPronephros and cloaca
DMesonephros and cloaca
EPronephros and coelom
A pregnant woman gives birth to her 1st child at the family farm. After delivery, the assisting midwife notices a triangular defect in the lower anterior abdominal wall of the baby. She clamps the umbilical cord with a cloth and urges the family to seek immediate medical care at the nearest hospital. Upon admission, the attending pediatrician further notices an open bladder plate with an exposed urethra, a low set umbilicus, an anteriorly displaced anus, and an inguinal hernia. No omphalocele is noted. The external genitalia is also affected. On physical exam, a shortened penis with a pronounced upward curvature and the urethral opening along the dorsal surface are also noted. What is the most likely diagnosis?
APosterior urethral valves
BBladder exstrophy
CBody stalk anomaly
DCloacal exstrophy
EUrachal cyst
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