Perineum development defects

Question 1

Urogenital sinus in females and males gives rise to:

Answer 1

Female

• lower part of vaginal canal & vestibule
• bladder
• urethra

Male

• Bladder
• Urethra

Question 2

Development of structures from cloaca

Answer 2

• Urorectal septum divides cloaca into urogenital sinus and rectum
  
  • Bladder
  • vestibule
  • rectum

Question 3

Development of 2 sets of genital ducts from indifferent stage

Answer 3

• Mesonephric duct (Wolffian) duct persists in males; regresses in females
• Paramesonephric duct (Mullerian) duct persists in females; regresses in males

Question 4

Development of Female Vaginal Canal from 2 Primorida

Answer 4

• Paramesonephric ducts from Uterine Tubes
  
  • Ducts fuse proximally to form uterus & Upper Vagina
• Lower vagina develops from Urogenital Sinus
  Uterovaginal Primordium induces Urogenital Sinus to form vaginal plate, which canalises to produce a vaginal lumen
  Vagina separated from vestibule by a Hymen
• Gubernaculum persists and becomes
  
  • Round ligaments
  • Ovarian ligaments

Question 5

Primordial phallus becomes?

Answer 5

Penis

Question 6

Urogenital folds become?

Answer 6

Urethral folds in male

Question 7

Urethral folds become?

Answer 7

Penile (spongy) urethra

Question 8

Scrotum derived from?

Answer 8

Labioscrotal swellings fuse over proximal urogenital folds to form scrotum

Question 9

Development of urethra

Answer 9

Male

• Proximal part: from Endoderm
• Glans portion: from Ectoderm
• Anesthesia (tip application) only required for initial portion of penile cath

Female

• formed entirely from urogenital sinus

Question 10

Urogenital sinus

Answer 10

• vesical part receives metanephric ducts & becomes bladder
• pelvic part (male) receives mesonephric ducts (ductus deferens)
• phallic part (male) grows out into genital tubercle as urethra

Question 11

Obliterated allantois becomes?

Answer 11

Urachus

Question 12

Hindgut

Answer 12

• Cloaca: distal part of hind gut
• Urorectal septum meets cloacal membrane, dividing it into Anal & Urogenital membranes
• Septum divides cloaca into dorsal anorectal canal and ventral urogenital sinus
• Area where the septum fuses with cloacal membrane is Perineal body
• Develops from Endoderm
• All (except Lower Rectum & Anal Canal)
  
  • receives blood via IMA,
  • innervation via Pelvic Splanchnics,
  • Lymph to I. Mesenteric Nodes
• Lower Rectum & Anal Canal above pectinate line develops from Endoderm.
  
  • Internal Iliac vessels
  • Pelvic Splanchnic innervations
  • Internal Iliac nodes lymph
• Anal canal below pectinate line is from proctodeum
  
  • Internal Iliac vessels
  • Pudendal (somatic) innervations
  • S. Inguinal nodes lymph